Merging upstream version 127.0.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
author: Daniel Baumann <daniel.baumann@progress-linux.org> 2024-06-12 05:43:14 +0000
committer: Daniel Baumann <daniel.baumann@progress-linux.org> 2024-06-12 05:43:14 +0000
commit: 8dd16259287f58f9273002717ec4d27e97127719 (patch)
tree: 3863e62a53829a84037444beab3abd4ed9dfc7d0 /third_party/rust/indexmap
parent: Releasing progress-linux version 126.0.1-1~progress7.99u1. (diff)
download: firefox-8dd16259287f58f9273002717ec4d27e97127719.tar.xz
firefox-8dd16259287f58f9273002717ec4d27e97127719.zip
32 files changed, 7175 insertions, 2999 deletions
diff --git a/third_party/rust/indexmap/.cargo-checksum.json b/third_party/rust/indexmap/.cargo-checksum.json
index 0f44683d7f..50a4338741 100644
--- a/third_party/rust/indexmap/.cargo-checksum.json
+++ b/third_party/rust/indexmap/.cargo-checksum.json
@@ -1 +1 @@
-{"files":{"Cargo.toml":"1290d383adfdcd24f158a4619afb5547d633c83c0a1ab3b5c1ee0dabe4fb1f36","LICENSE-APACHE":"a60eea817514531668d7e00765731449fe14d059d3249e0bc93b36de45f759f2","LICENSE-MIT":"ecc269ef87fd38a1d98e30bfac9ba964a9dbd9315c3770fed98d4d7cb5882055","README.md":"f8b02aa7c20fc0f5bc13de9e9e78899ec8cdbc16c2db880a1d0bc14c25b07542","RELEASES.md":"85d9d9bc78e94df7ce90300bb94099b9ab2696d1b3f6b815c22761522878e679","benches/bench.rs":"3b2900abbc9e8a60af78b0395222ee75e86bc68519a0f38477387d1572eed397","benches/faststring.rs":"5fdd6cdb19d0557ed58f241e809a240cf8939d9e5b87a72d5f127f81ab98380b","build.rs":"558b4d0b9e9b3a44f7e1a2b69f7a7567ea721cd45cb54f4e458e850bf702f35c","src/arbitrary.rs":"bb8bda10f686abe57eef1446d3fc3fc6fb251f95629b28c20e620a4838c43db8","src/equivalent.rs":"2e6ae24ef09a09b917f4e2b0f6288f901878e42f5080f61b1bd1afdcc90aba87","src/lib.rs":"ea2cbe4f6cc2c4a75f42c9fc936503e6bee0f136c60f6811a2a9907ed8886443","src/macros.rs":"80c22f630e7f81e6fa663ca4c9e50cf5f332c8905d72d1338bd16f24eb353c2a","src/map.rs":"2e9cbfa240865cfd6b6b972bdbdb39283e6302dd2d0d72b3c2bfce4414bf5729","src/map/core.rs":"8422cd774c5db7d83cdeb0c5836c10f29caa1bee8d95b0d674b01b32e7ce80d8","src/map/core/raw.rs":"4e5fac4fecccc352268351d8b1f82b345067b5c029bba7e6ab88e8f8bc799c6a","src/mutable_keys.rs":"a919065b59000286eb11c7d46f6896bf0a1d484c9dac5e61d80bb8990c9fbedb","src/rayon/map.rs":"1a508c7c95c5d56113b851f7ce140d62ad541f1c6129352a7ec62d5bea7af4a1","src/rayon/mod.rs":"019e9379ccab57a299ab5b5a2c0efc7561b77a715a5afe8f797c7e8330c6206c","src/rayon/set.rs":"ba00e88e90fb7ab803589f99f24b595d60309e541aae3d01fdde21bff3840194","src/rustc.rs":"fe7a348c5a10a66880cb6c737593fe79d3b6de40f44ba0d7b89204aa95e14a3a","src/serde.rs":"d45ec8fb9c02594ca6f2e9b20764778b2b4193a24a52f1e233160a33efc6e683","src/serde_seq.rs":"c54a52fa607b6ccddda1e76e829778ca304c49b5f434edc5e582a5386c35d662","src/set.rs":"0a57affb623fa6b28df18cc14841e4f076cbd1da5c809635d202f865640af1ee","src/util.rs":"ab712bce71b54cf2763e6010e64bb5944d1d59ce15e2f2beffa7ceed204d6a68","tests/equivalent_trait.rs":"efe9393069e3cfc893d2c9c0343679979578e437fdb98a10baefeced027ba310","tests/macros_full_path.rs":"c33c86d7341581fdd08e2e6375a4afca507fa603540c54a3b9e51c4cd011cd71","tests/quick.rs":"1addbc6cbcb1aae5b8bde0fb0e18197d947e8f13244e4ae7ebf97bdda00eafea","tests/tests.rs":"f6dbeeb0e2950402b0e66ac52bf74c9e4197d3c5d9c0dde64a7998a2ef74d327"},"package":"bd070e393353796e801d209ad339e89596eb4c8d430d18ede6a1cced8fafbd99"}
-\ No newline at end of file
+{"files":{"Cargo.toml":"34db4bcb2f85a5e3980eb06d3ec4aac3fa0ef6ff48b57ef28aba6dfc1fbeedbb","LICENSE-APACHE":"a60eea817514531668d7e00765731449fe14d059d3249e0bc93b36de45f759f2","LICENSE-MIT":"ecc269ef87fd38a1d98e30bfac9ba964a9dbd9315c3770fed98d4d7cb5882055","README.md":"98781168dcaf64ed3eecbf7146311045433773486259a372b985c9ae28545017","RELEASES.md":"0f8b4d3a352bddda55384f2ffa804b39e7d73aefa27364c56378d0043756e491","benches/bench.rs":"3b2900abbc9e8a60af78b0395222ee75e86bc68519a0f38477387d1572eed397","benches/faststring.rs":"5fdd6cdb19d0557ed58f241e809a240cf8939d9e5b87a72d5f127f81ab98380b","src/arbitrary.rs":"068713b1e8e762dbe9e4d19d555e77c17e59408335a40f4777d6100340605655","src/borsh.rs":"74121b426379d4f7365757ffd4f3dd469543fa1635193460fe268799a78a0706","src/lib.rs":"57ca834c31a7bb70821f476de916486ab58b9ad3922761153972b5f3923fe078","src/macros.rs":"1493afee2db2c9744be99e5fc32d0cd3742b8a3dbb31fa786ebbe28f1387e7d6","src/map.rs":"d1422353531e6114778033e901b30c8138da048075582fb396d299211958044c","src/map/core.rs":"eb291748598e1aa9112ee068a9a5fea7b1190114c4007de179528408f7439faa","src/map/core/entry.rs":"7d987cc5099099e0c9020afa7b3c23d20f11812dce9d684db03ff390f4068691","src/map/core/raw.rs":"30cc048f7c7f0deb2eb1c699a15e6b18dff1187404228c55e404c0d5bfe11f3e","src/map/core/raw_entry_v1.rs":"0942938c167aca6c892bd78e431d2b7366443e1d6f4f0d930b0bf72ca3ab8054","src/map/iter.rs":"ae0023c1ccc78ac765dc43fe51f233f2fca1ebba132490db8429941183d2c497","src/map/mutable.rs":"9d8dded5a95a21fba2d97ef64610627fae97dffc096e872b0c378ae8b63de53b","src/map/serde_seq.rs":"ce06b5bb816c15ea8fe3d2c358baa90fe6f45ecb585623a69592d6de69319194","src/map/slice.rs":"c0d770a6ce47fa4f3d9c82b468504c567dc4031d8f3694603e2b5bcc295cf3e1","src/map/tests.rs":"714674a55103dc57c16d9fe2916d462a655dc217e079a7e0ed5a62ab0f9749f1","src/rayon/map.rs":"0fad36851fdf6894695e526c684c9b3afeac82e29016e6a523eea68cc3b2d19d","src/rayon/mod.rs":"1c9c13b5cf6974f652ded53b014774944c761f079a77a61b3bc52eaa3d4b972b","src/rayon/set.rs":"4b076dbfd9a7eb2fd65783f1c8a5acabe075403f3d05e30c337676acec25d8ee","src/rustc.rs":"fe7a348c5a10a66880cb6c737593fe79d3b6de40f44ba0d7b89204aa95e14a3a","src/serde.rs":"23fd6b5e8f6795e4121693ac16dab61e76c4d8c83e6da1b3ef26d081fae28e79","src/set.rs":"fe9ca3fea8c1156a13ffccdf49d8acb9c79433586c1dfc71ef21ecfcebfd8b14","src/set/iter.rs":"a387c48eff0338b5c8f4e2059403bd665a9c8037634cc5860f80b72a4fbbed30","src/set/mutable.rs":"83ac1719a5eb5bdefac0e9eaa87b80ed98e39c5f2bb4cb69143e3fbff4302e6d","src/set/slice.rs":"9b5aa57e3510d5e17a91a6eaa2ee66a3d79d40b171beb86f7dd9208277135900","src/set/tests.rs":"d9c182cd776ca9182b5284f06eacc70c5f33a66aff3021c35134ffd1d7630c05","src/util.rs":"dbd57cfdac2a72db8c5ce83bf288bcaf33b5ae59adddcd088792a624c4c0e909","tests/equivalent_trait.rs":"efe9393069e3cfc893d2c9c0343679979578e437fdb98a10baefeced027ba310","tests/macros_full_path.rs":"c33c86d7341581fdd08e2e6375a4afca507fa603540c54a3b9e51c4cd011cd71","tests/quick.rs":"9759dcc34d86d9635d9d18be6358f5f3e3c0f995874b64b5a7ca4b582f4acedb","tests/tests.rs":"f6dbeeb0e2950402b0e66ac52bf74c9e4197d3c5d9c0dde64a7998a2ef74d327"},"package":"168fb715dda47215e360912c096649d23d58bf392ac62f73919e831745e40f26"}
+\ No newline at end of file
diff --git a/third_party/rust/indexmap/Cargo.toml b/third_party/rust/indexmap/Cargo.toml
index 28f3618f01..51d6e6e97c 100644
--- a/third_party/rust/indexmap/Cargo.toml
+++ b/third_party/rust/indexmap/Cargo.toml
@@ -11,9 +11,9 @@
 
 [package]
 edition = "2021"
-rust-version = "1.56"
+rust-version = "1.63"
 name = "indexmap"
-version = "1.9.3"
+version = "2.2.6"
 description = "A hash table with consistent order and fast iteration."
 documentation = "https://docs.rs/indexmap/"
 readme = "README.md"
@@ -26,22 +26,27 @@ categories = [
     "no-std",
 ]
 license = "Apache-2.0 OR MIT"
-repository = "https://github.com/bluss/indexmap"
-
-[package.metadata.release]
-no-dev-version = true
-tag-name = "{{version}}"
+repository = "https://github.com/indexmap-rs/indexmap"
 
 [package.metadata.docs.rs]
 features = [
     "arbitrary",
     "quickcheck",
-    "serde-1",
+    "serde",
+    "borsh",
     "rayon",
 ]
+rustdoc-args = [
+    "--cfg",
+    "docsrs",
+]
+
+[package.metadata.release]
+no-dev-version = true
+tag-name = "{{version}}"
 
 [profile.bench]
-debug = true
+debug = 2
 
 [lib]
 bench = false
@@ -51,8 +56,17 @@ version = "1.0"
 optional = true
 default-features = false
 
+[dependencies.borsh]
+version = "1.2"
+optional = true
+default-features = false
+
+[dependencies.equivalent]
+version = "1.0"
+default-features = false
+
 [dependencies.hashbrown]
-version = "0.12"
+version = "0.14.1"
 features = ["raw"]
 default-features = false
 
@@ -62,7 +76,7 @@ optional = true
 default-features = false
 
 [dependencies.rayon]
-version = "1.4.1"
+version = "1.5.3"
 optional = true
 
 [dependencies.rustc-rayon]
@@ -82,7 +96,7 @@ version = "1.0"
 version = "0.2.1"
 
 [dev-dependencies.itertools]
-version = "0.10"
+version = "0.12"
 
 [dev-dependencies.lazy_static]
 version = "1.3"
@@ -98,11 +112,10 @@ features = ["small_rng"]
 [dev-dependencies.serde_derive]
 version = "1.0"
 
-[build-dependencies.autocfg]
-version = "1"
-
 [features]
-serde-1 = ["serde"]
+default = ["std"]
 std = []
 test_debug = []
-test_low_transition_point = []
+
+[lints.clippy]
+style = "allow"
diff --git a/third_party/rust/indexmap/README.md b/third_party/rust/indexmap/README.md
index d80b7099ce..9112d52893 100644
--- a/third_party/rust/indexmap/README.md
+++ b/third_party/rust/indexmap/README.md
@@ -1,9 +1,9 @@
 # indexmap
 
-[![build status](https://github.com/bluss/indexmap/workflows/Continuous%20integration/badge.svg?branch=master)](https://github.com/bluss/indexmap/actions)
+[![build status](https://github.com/indexmap-rs/indexmap/workflows/Continuous%20integration/badge.svg?branch=master)](https://github.com/indexmap-rs/indexmap/actions)
 [![crates.io](https://img.shields.io/crates/v/indexmap.svg)](https://crates.io/crates/indexmap)
 [![docs](https://docs.rs/indexmap/badge.svg)](https://docs.rs/indexmap)
-[![rustc](https://img.shields.io/badge/rust-1.56%2B-orange.svg)](https://img.shields.io/badge/rust-1.56%2B-orange.svg)
+[![rustc](https://img.shields.io/badge/rust-1.63%2B-orange.svg)](https://img.shields.io/badge/rust-1.63%2B-orange.svg)
 
 A pure-Rust hash table which preserves (in a limited sense) insertion order.
 
@@ -26,7 +26,9 @@ was indexmap, a hash table that has following properties:
 - Order is **independent of hash function** and hash values of keys.
 - Fast to iterate.
 - Indexed in compact space.
-- Preserves insertion order **as long** as you don't call `.remove()`.
+- Preserves insertion order **as long** as you don't call `.remove()`,
+  `.swap_remove()`, or other methods that explicitly change order.
+  The alternate `.shift_remove()` does preserve relative order.
 - Uses hashbrown for the inner table, just like Rust's libstd `HashMap` does.
 
 ## Performance
@@ -52,4 +54,4 @@ which is roughly:
 
 # Recent Changes
 
-See [RELEASES.md](https://github.com/bluss/indexmap/blob/master/RELEASES.md).
+See [RELEASES.md](https://github.com/indexmap-rs/indexmap/blob/master/RELEASES.md).
diff --git a/third_party/rust/indexmap/RELEASES.md b/third_party/rust/indexmap/RELEASES.md
index 7ea8b702e0..8c033db042 100644
--- a/third_party/rust/indexmap/RELEASES.md
+++ b/third_party/rust/indexmap/RELEASES.md
@@ -1,388 +1,508 @@
-- 1.9.3
+# Releases
 
-  - Bump the `rustc-rayon` dependency, for compiler use only.
+## 2.2.6
 
-- 1.9.2
+- Added trait `MutableValues` for opt-in mutable access to set values.
 
-  - `IndexMap` and `IndexSet` both implement `arbitrary::Arbitrary<'_>` and
-    `quickcheck::Arbitrary` if those optional dependency features are enabled.
+## 2.2.5
 
-- 1.9.1
+- Added optional `borsh` serialization support.
 
-  - The MSRV now allows Rust 1.56.0 as well. However, currently `hashbrown`
-    0.12.1 requires 1.56.1, so users on 1.56.0 should downgrade that to 0.12.0
-    until there is a later published version relaxing its requirement.
+## 2.2.4
 
-- 1.9.0
+- Added an `insert_sorted` method on `IndexMap`, `IndexSet`, and `VacantEntry`.
+- Avoid hashing for lookups in single-entry maps.
+- Limit preallocated memory in `serde` deserializers.
 
-  - **MSRV**: Rust 1.56.1 or later is now required.
+## 2.2.3
 
-  - The `hashbrown` dependency has been updated to version 0.12.
+- Added `move_index` and `swap_indices` methods to `IndexedEntry`,
+  `OccupiedEntry`, and `RawOccupiedEntryMut`, functioning like the existing
+  methods on `IndexMap`.
+- Added `shift_insert` methods on `VacantEntry` and `RawVacantEntryMut`, as
+  well as `shift_insert_hashed_nocheck` on the latter, to insert the new entry
+  at a particular index.
+- Added `shift_insert` methods on `IndexMap` and `IndexSet` to insert a new
+  entry at a particular index, or else move an existing entry there.
 
-  - `IterMut` and `ValuesMut` now implement `Debug`.
+## 2.2.2
 
-  - The new `IndexMap::shrink_to` and `IndexSet::shrink_to` methods shrink
-    the capacity with a lower bound.
+- Added indexing methods to raw entries: `RawEntryBuilder::from_hash_full`,
+  `RawEntryBuilder::index_from_hash`, and `RawEntryMut::index`.
 
-  - The new `IndexMap::move_index` and `IndexSet::move_index` methods change
-    the position of an item from one index to another, shifting the items
-    between to accommodate the move.
+## 2.2.1
 
-- 1.8.2
+- Corrected the signature of `RawOccupiedEntryMut::into_key(self) -> &'a mut K`,
+  This a breaking change from 2.2.0, but that version was published for less
+  than a day and has now been yanked.
 
-  - Bump the `rustc-rayon` dependency, for compiler use only.
+## 2.2.0
 
-- 1.8.1
+- The new `IndexMap::get_index_entry` method finds an entry by its index for
+  in-place manipulation.
 
-  - The new `IndexSet::replace_full` will return the index of the item along
-    with the replaced value, if any, by @zakcutner in PR [222].
+- The `Keys` iterator now implements `Index<usize>` for quick access to the
+  entry's key, compared to indexing the map to get the value.
 
-[222]: https://github.com/bluss/indexmap/pull/222
+- The new `IndexMap::splice` and `IndexSet::splice` methods will drain the
+  given range as an iterator, and then replace that range with entries from
+  an input iterator.
 
-- 1.8.0
+- The new trait `RawEntryApiV1` offers opt-in access to a raw entry API for
+  `IndexMap`, corresponding to the unstable API on `HashSet` as of Rust 1.75.
 
-  - The new `IndexMap::into_keys` and `IndexMap::into_values` will consume
-    the map into keys or values, respectively, matching Rust 1.54's `HashMap`
-    methods, by @taiki-e in PR [195].
+- Many `IndexMap` and `IndexSet` methods have relaxed their type constraints,
+  e.g. removing `K: Hash` on methods that don't actually need to hash.
 
-  - More of the iterator types implement `Debug`, `ExactSizeIterator`, and
-    `FusedIterator`, by @cuviper in PR [196].
+- Removal methods `remove`, `remove_entry`, and `take` are now deprecated
+  in favor of their `shift_` or `swap_` prefixed variants, which are more
+  explicit about their effect on the index and order of remaining items.
+  The deprecated methods will remain to guide drop-in replacements from
+  `HashMap` and `HashSet` toward the prefixed methods.
 
-  - `IndexMap` and `IndexSet` now implement rayon's `ParallelDrainRange`,
-    by @cuviper in PR [197].
+## 2.1.0
 
-  - `IndexMap::with_hasher` and `IndexSet::with_hasher` are now `const`
-    functions, allowing static maps and sets, by @mwillsey in PR [203].
+- Empty slices can now be created with `map::Slice::{new, new_mut}` and
+  `set::Slice::new`. In addition, `Slice::new`, `len`, and `is_empty` are
+  now `const` functions on both types.
 
-  - `IndexMap` and `IndexSet` now implement `From` for arrays, matching
-    Rust 1.56's implementation for `HashMap`, by @rouge8 in PR [205].
+- `IndexMap`, `IndexSet`, and their respective `Slice`s all have binary
+  search methods for sorted data: map `binary_search_keys` and set
+  `binary_search` for plain comparison, `binary_search_by` for custom
+  comparators, `binary_search_by_key` for key extraction, and
+  `partition_point` for boolean conditions.
 
-  - `IndexMap` and `IndexSet` now have methods `sort_unstable_keys`,
-    `sort_unstable_by`, `sorted_unstable_by`, and `par_*` equivalents,
-    which sort in-place without preserving the order of equal items, by
-    @bhgomes in PR [211].
+## 2.0.2
 
-[195]: https://github.com/bluss/indexmap/pull/195
-[196]: https://github.com/bluss/indexmap/pull/196
-[197]: https://github.com/bluss/indexmap/pull/197
-[203]: https://github.com/bluss/indexmap/pull/203
-[205]: https://github.com/bluss/indexmap/pull/205
-[211]: https://github.com/bluss/indexmap/pull/211
+- The `hashbrown` dependency has been updated to version 0.14.1 to
+  complete the support for Rust 1.63.
 
-- 1.7.0
+## 2.0.1
 
-  - **MSRV**: Rust 1.49 or later is now required.
+- **MSRV**: Rust 1.63.0 is now supported as well, pending publication of
+  `hashbrown`'s relaxed MSRV (or use cargo `--ignore-rust-version`).
 
-  - The `hashbrown` dependency has been updated to version 0.11.
+## 2.0.0
 
-- 1.6.2
+- **MSRV**: Rust 1.64.0 or later is now required.
 
-  - Fixed to match `std` behavior, `OccupiedEntry::key` now references the
-    existing key in the map instead of the lookup key, by @cuviper in PR [170].
+- The `"std"` feature is no longer auto-detected. It is included in the
+  default feature set, or else can be enabled like any other Cargo feature.
 
-  - The new `Entry::or_insert_with_key` matches Rust 1.50's `Entry` method,
-    passing `&K` to the callback to create a value, by @cuviper in PR [175].
+- The `"serde-1"` feature has been removed, leaving just the optional
+  `"serde"` dependency to be enabled like a feature itself.
 
-[170]: https://github.com/bluss/indexmap/pull/170
-[175]: https://github.com/bluss/indexmap/pull/175
+- `IndexMap::get_index_mut` now returns `Option<(&K, &mut V)>`, changing
+  the key part from `&mut K` to `&K`. There is also a new alternative
+  `MutableKeys::get_index_mut2` to access the former behavior.
 
-- 1.6.1
+- The new `map::Slice<K, V>` and `set::Slice<T>` offer a linear view of maps
+  and sets, behaving a lot like normal `[(K, V)]` and `[T]` slices. Notably,
+  comparison traits like `Eq` only consider items in order, rather than hash
+  lookups, and slices even implement `Hash`.
 
-  - The new `serde_seq` module implements `IndexMap` serialization as a
-    sequence to ensure order is preserved, by @cuviper in PR [158].
+- `IndexMap` and `IndexSet` now have `sort_by_cached_key` and
+  `par_sort_by_cached_key` methods which perform stable sorts in place
+  using a key extraction function.
 
-  - New methods on maps and sets work like the `Vec`/slice methods by the same name:
-    `truncate`, `split_off`, `first`, `first_mut`, `last`, `last_mut`, and
-    `swap_indices`, by @cuviper in PR [160].
+- `IndexMap` and `IndexSet` now have `reserve_exact`, `try_reserve`, and
+  `try_reserve_exact` methods that correspond to the same methods on `Vec`.
+  However, exactness only applies to the direct capacity for items, while the
+  raw hash table still follows its own rules for capacity and load factor.
 
-[158]: https://github.com/bluss/indexmap/pull/158
-[160]: https://github.com/bluss/indexmap/pull/160
+- The `Equivalent` trait is now re-exported from the `equivalent` crate,
+  intended as a common base to allow types to work with multiple map types.
 
-- 1.6.0
+- The `hashbrown` dependency has been updated to version 0.14.
 
-  - **MSRV**: Rust 1.36 or later is now required.
+- The `serde_seq` module has been moved from the crate root to below the
+  `map` module.
 
-  - The `hashbrown` dependency has been updated to version 0.9.
+## 1.9.3
 
-- 1.5.2
+- Bump the `rustc-rayon` dependency, for compiler use only.
 
-  - The new "std" feature will force the use of `std` for users that explicitly
-    want the default `S = RandomState`, bypassing the autodetection added in 1.3.0,
-    by @cuviper in PR [145].
+## 1.9.2
 
-[145]: https://github.com/bluss/indexmap/pull/145
+- `IndexMap` and `IndexSet` both implement `arbitrary::Arbitrary<'_>` and
+  `quickcheck::Arbitrary` if those optional dependency features are enabled.
 
-- 1.5.1
+## 1.9.1
 
-  - Values can now be indexed by their `usize` position by @cuviper in PR [132].
+- The MSRV now allows Rust 1.56.0 as well. However, currently `hashbrown`
+  0.12.1 requires 1.56.1, so users on 1.56.0 should downgrade that to 0.12.0
+  until there is a later published version relaxing its requirement.
 
-  - Some of the generic bounds have been relaxed to match `std` by @cuviper in PR [141].
+## 1.9.0
 
-  - `drain` now accepts any `R: RangeBounds<usize>` by @cuviper in PR [142].
+- **MSRV**: Rust 1.56.1 or later is now required.
 
-[132]: https://github.com/bluss/indexmap/pull/132
-[141]: https://github.com/bluss/indexmap/pull/141
-[142]: https://github.com/bluss/indexmap/pull/142
+- The `hashbrown` dependency has been updated to version 0.12.
 
-- 1.5.0
+- `IterMut` and `ValuesMut` now implement `Debug`.
 
-  - **MSRV**: Rust 1.32 or later is now required.
+- The new `IndexMap::shrink_to` and `IndexSet::shrink_to` methods shrink
+  the capacity with a lower bound.
 
-  - The inner hash table is now based on `hashbrown` by @cuviper in PR [131].
-    This also completes the method `reserve` and adds `shrink_to_fit`.
+- The new `IndexMap::move_index` and `IndexSet::move_index` methods change
+  the position of an item from one index to another, shifting the items
+  between to accommodate the move.
 
-  - Add new methods `get_key_value`, `remove_entry`, `swap_remove_entry`,
-    and `shift_remove_entry`, by @cuviper in PR [136]
+## 1.8.2
 
-  - `Clone::clone_from` reuses allocations by @cuviper in PR [125]
+- Bump the `rustc-rayon` dependency, for compiler use only.
 
-  - Add new method `reverse` by @linclelinkpart5 in PR [128]
+## 1.8.1
 
-[125]: https://github.com/bluss/indexmap/pull/125
-[128]: https://github.com/bluss/indexmap/pull/128
-[131]: https://github.com/bluss/indexmap/pull/131
-[136]: https://github.com/bluss/indexmap/pull/136
+- The new `IndexSet::replace_full` will return the index of the item along
+  with the replaced value, if any, by @zakcutner in PR [222].
 
-- 1.4.0
+[222]: https://github.com/indexmap-rs/indexmap/pull/222
 
-  - Add new method `get_index_of` by @Thermatrix in PR [115] and [120]
+## 1.8.0
 
-  - Fix build script rebuild-if-changed configuration to use "build.rs";
-    fixes issue [123]. Fix by @cuviper.
+- The new `IndexMap::into_keys` and `IndexMap::into_values` will consume
+  the map into keys or values, respectively, matching Rust 1.54's `HashMap`
+  methods, by @taiki-e in PR [195].
 
-  - Dev-dependencies (rand and quickcheck) have been updated. The crate's tests
-    now run using Rust 1.32 or later (MSRV for building the crate has not changed).
-    by @kjeremy and @bluss
+- More of the iterator types implement `Debug`, `ExactSizeIterator`, and
+  `FusedIterator`, by @cuviper in PR [196].
 
-[123]: https://github.com/bluss/indexmap/issues/123
-[115]: https://github.com/bluss/indexmap/pull/115
-[120]: https://github.com/bluss/indexmap/pull/120
+- `IndexMap` and `IndexSet` now implement rayon's `ParallelDrainRange`,
+  by @cuviper in PR [197].
 
-- 1.3.2
+- `IndexMap::with_hasher` and `IndexSet::with_hasher` are now `const`
+  functions, allowing static maps and sets, by @mwillsey in PR [203].
 
-  - Maintenance update to regenerate the published `Cargo.toml`.
+- `IndexMap` and `IndexSet` now implement `From` for arrays, matching
+  Rust 1.56's implementation for `HashMap`, by @rouge8 in PR [205].
 
-- 1.3.1
+- `IndexMap` and `IndexSet` now have methods `sort_unstable_keys`,
+  `sort_unstable_by`, `sorted_unstable_by`, and `par_*` equivalents,
+  which sort in-place without preserving the order of equal items, by
+  @bhgomes in PR [211].
 
-  - Maintenance update for formatting and `autocfg` 1.0.
+[195]: https://github.com/indexmap-rs/indexmap/pull/195
+[196]: https://github.com/indexmap-rs/indexmap/pull/196
+[197]: https://github.com/indexmap-rs/indexmap/pull/197
+[203]: https://github.com/indexmap-rs/indexmap/pull/203
+[205]: https://github.com/indexmap-rs/indexmap/pull/205
+[211]: https://github.com/indexmap-rs/indexmap/pull/211
 
-- 1.3.0
+## 1.7.0
 
-  - The deprecation messages in the previous version have been removed.
-    (The methods have not otherwise changed.) Docs for removal methods have been
-    improved.
-  - From Rust 1.36, this crate supports being built **without std**, requiring
-    `alloc` instead. This is enabled automatically when it is detected that
-    `std` is not available. There is no crate feature to enable/disable to
-    trigger this. The new build-dep `autocfg` enables this.
+- **MSRV**: Rust 1.49 or later is now required.
 
-- 1.2.0
+- The `hashbrown` dependency has been updated to version 0.11.
 
-  - Plain `.remove()` now has a deprecation message, it informs the user
-    about picking one of the removal functions `swap_remove` and `shift_remove`
-    which have different performance and order semantics.
-    Plain `.remove()` will not be removed, the warning message and method
-    will remain until further.
+## 1.6.2
 
-  - Add new method `shift_remove` for order preserving removal on the map,
-    and `shift_take` for the corresponding operation on the set.
+- Fixed to match `std` behavior, `OccupiedEntry::key` now references the
+  existing key in the map instead of the lookup key, by @cuviper in PR [170].
 
-  - Add methods `swap_remove`, `swap_remove_entry` to `Entry`.
+- The new `Entry::or_insert_with_key` matches Rust 1.50's `Entry` method,
+  passing `&K` to the callback to create a value, by @cuviper in PR [175].
 
-  - Fix indexset/indexmap to support full paths, like `indexmap::indexmap!()`
+[170]: https://github.com/indexmap-rs/indexmap/pull/170
+[175]: https://github.com/indexmap-rs/indexmap/pull/175
 
-  - Internal improvements: fix warnings, deprecations and style lints
+## 1.6.1
 
-- 1.1.0
+- The new `serde_seq` module implements `IndexMap` serialization as a
+  sequence to ensure order is preserved, by @cuviper in PR [158].
 
-  - Added optional feature `"rayon"` that adds parallel iterator support
-    to `IndexMap` and `IndexSet` using Rayon. This includes all the regular
-    iterators in parallel versions, and parallel sort.
+- New methods on maps and sets work like the `Vec`/slice methods by the same name:
+  `truncate`, `split_off`, `first`, `first_mut`, `last`, `last_mut`, and
+  `swap_indices`, by @cuviper in PR [160].
 
-  - Implemented `Clone` for `map::{Iter, Keys, Values}` and
-    `set::{Difference, Intersection, Iter, SymmetricDifference, Union}`
+[158]: https://github.com/indexmap-rs/indexmap/pull/158
+[160]: https://github.com/indexmap-rs/indexmap/pull/160
 
-  - Implemented `Debug` for `map::{Entry, IntoIter, Iter, Keys, Values}` and
-    `set::{Difference, Intersection, IntoIter, Iter, SymmetricDifference, Union}`
+## 1.6.0
 
-  - Serde trait `IntoDeserializer` are implemented for `IndexMap` and `IndexSet`.
+- **MSRV**: Rust 1.36 or later is now required.
 
-  - Minimum Rust version requirement increased to Rust 1.30 for development builds.
+- The `hashbrown` dependency has been updated to version 0.9.
 
-- 1.0.2
+## 1.5.2
 
-  - The new methods `IndexMap::insert_full` and `IndexSet::insert_full` are
-    both like `insert` with the index included in the return value.
+- The new "std" feature will force the use of `std` for users that explicitly
+  want the default `S = RandomState`, bypassing the autodetection added in 1.3.0,
+  by @cuviper in PR [145].
 
-  - The new method `Entry::and_modify` can be used to modify occupied
-    entries, matching the new methods of `std` maps in Rust 1.26.
+[145]: https://github.com/indexmap-rs/indexmap/pull/145
 
-  - The new method `Entry::or_default` inserts a default value in unoccupied
-    entries, matching the new methods of `std` maps in Rust 1.28.
+## 1.5.1
 
-- 1.0.1
+- Values can now be indexed by their `usize` position by @cuviper in PR [132].
 
-  - Document Rust version policy for the crate (see rustdoc)
+- Some of the generic bounds have been relaxed to match `std` by @cuviper in PR [141].
 
-- 1.0.0
+- `drain` now accepts any `R: RangeBounds<usize>` by @cuviper in PR [142].
 
-  - This is the 1.0 release for `indexmap`! (the crate and datastructure
-    formerly known as “ordermap”)
-  - `OccupiedEntry::insert` changed its signature, to use `&mut self` for
-    the method receiver, matching the equivalent method for a standard
-    `HashMap`.  Thanks to @dtolnay for finding this bug.
-  - The deprecated old names from ordermap were removed: `OrderMap`,
-    `OrderSet`, `ordermap!{}`, `orderset!{}`. Use the new `IndexMap`
-    etc names instead.
+[132]: https://github.com/indexmap-rs/indexmap/pull/132
+[141]: https://github.com/indexmap-rs/indexmap/pull/141
+[142]: https://github.com/indexmap-rs/indexmap/pull/142
 
-- 0.4.1
+## 1.5.0
 
-  - Renamed crate to `indexmap`; the `ordermap` crate is now deprecated
-    and the types `OrderMap/Set` now have a deprecation notice.
+- **MSRV**: Rust 1.32 or later is now required.
 
-- 0.4.0
+- The inner hash table is now based on `hashbrown` by @cuviper in PR [131].
+  This also completes the method `reserve` and adds `shrink_to_fit`.
 
-  - This is the last release series for this `ordermap` under that name,
-    because the crate is **going to be renamed** to `indexmap` (with types
-    `IndexMap`, `IndexSet`) and no change in functionality!
-  - The map and its associated structs moved into the `map` submodule of the
-    crate, so that the map and set are symmetric
+- Add new methods `get_key_value`, `remove_entry`, `swap_remove_entry`,
+  and `shift_remove_entry`, by @cuviper in PR [136]
+
+- `Clone::clone_from` reuses allocations by @cuviper in PR [125]
+
+- Add new method `reverse` by @linclelinkpart5 in PR [128]
+
+[125]: https://github.com/indexmap-rs/indexmap/pull/125
+[128]: https://github.com/indexmap-rs/indexmap/pull/128
+[131]: https://github.com/indexmap-rs/indexmap/pull/131
+[136]: https://github.com/indexmap-rs/indexmap/pull/136
+
+## 1.4.0
+
+- Add new method `get_index_of` by @Thermatrix in PR [115] and [120]
+
+- Fix build script rebuild-if-changed configuration to use "build.rs";
+  fixes issue [123]. Fix by @cuviper.
+
+- Dev-dependencies (rand and quickcheck) have been updated. The crate's tests
+  now run using Rust 1.32 or later (MSRV for building the crate has not changed).
+  by @kjeremy and @bluss
+
+[123]: https://github.com/indexmap-rs/indexmap/issues/123
+[115]: https://github.com/indexmap-rs/indexmap/pull/115
+[120]: https://github.com/indexmap-rs/indexmap/pull/120
+
+## 1.3.2
+
+- Maintenance update to regenerate the published `Cargo.toml`.
+
+## 1.3.1
+
+- Maintenance update for formatting and `autocfg` 1.0.
+
+## 1.3.0
+
+- The deprecation messages in the previous version have been removed.
+  (The methods have not otherwise changed.) Docs for removal methods have been
+  improved.
+- From Rust 1.36, this crate supports being built **without std**, requiring
+  `alloc` instead. This is enabled automatically when it is detected that
+  `std` is not available. There is no crate feature to enable/disable to
+  trigger this. The new build-dep `autocfg` enables this.
+
+## 1.2.0
+
+- Plain `.remove()` now has a deprecation message, it informs the user
+  about picking one of the removal functions `swap_remove` and `shift_remove`
+  which have different performance and order semantics.
+  Plain `.remove()` will not be removed, the warning message and method
+  will remain until further.
+
+- Add new method `shift_remove` for order preserving removal on the map,
+  and `shift_take` for the corresponding operation on the set.
+
+- Add methods `swap_remove`, `swap_remove_entry` to `Entry`.
+
+- Fix indexset/indexmap to support full paths, like `indexmap::indexmap!()`
+
+- Internal improvements: fix warnings, deprecations and style lints
+
+## 1.1.0
+
+- Added optional feature `"rayon"` that adds parallel iterator support
+  to `IndexMap` and `IndexSet` using Rayon. This includes all the regular
+  iterators in parallel versions, and parallel sort.
+
+- Implemented `Clone` for `map::{Iter, Keys, Values}` and
+  `set::{Difference, Intersection, Iter, SymmetricDifference, Union}`
+
+- Implemented `Debug` for `map::{Entry, IntoIter, Iter, Keys, Values}` and
+  `set::{Difference, Intersection, IntoIter, Iter, SymmetricDifference, Union}`
+
+- Serde trait `IntoDeserializer` are implemented for `IndexMap` and `IndexSet`.
+
+- Minimum Rust version requirement increased to Rust 1.30 for development builds.
+
+## 1.0.2
+
+- The new methods `IndexMap::insert_full` and `IndexSet::insert_full` are
+  both like `insert` with the index included in the return value.
+
+- The new method `Entry::and_modify` can be used to modify occupied
+  entries, matching the new methods of `std` maps in Rust 1.26.
+
+- The new method `Entry::or_default` inserts a default value in unoccupied
+  entries, matching the new methods of `std` maps in Rust 1.28.
+
+## 1.0.1
+
+- Document Rust version policy for the crate (see rustdoc)
+
+## 1.0.0
+
+- This is the 1.0 release for `indexmap`! (the crate and datastructure
+  formerly known as “ordermap”)
+- `OccupiedEntry::insert` changed its signature, to use `&mut self` for
+  the method receiver, matching the equivalent method for a standard
+  `HashMap`.  Thanks to @dtolnay for finding this bug.
+- The deprecated old names from ordermap were removed: `OrderMap`,
+  `OrderSet`, `ordermap!{}`, `orderset!{}`. Use the new `IndexMap`
+  etc names instead.
+
+## 0.4.1
+
+- Renamed crate to `indexmap`; the `ordermap` crate is now deprecated
+  and the types `OrderMap/Set` now have a deprecation notice.
+
+## 0.4.0
+
+- This is the last release series for this `ordermap` under that name,
+  because the crate is **going to be renamed** to `indexmap` (with types
+  `IndexMap`, `IndexSet`) and no change in functionality!
+- The map and its associated structs moved into the `map` submodule of the
+  crate, so that the map and set are symmetric
 
     + The iterators, `Entry` and other structs are now under `ordermap::map::`
 
-  - Internally refactored `OrderMap<K, V, S>` so that all the main algorithms
-    (insertion, lookup, removal etc) that don't use the `S` parameter (the
-    hasher) are compiled without depending on `S`, which reduces generics bloat.
+- Internally refactored `OrderMap<K, V, S>` so that all the main algorithms
+  (insertion, lookup, removal etc) that don't use the `S` parameter (the
+  hasher) are compiled without depending on `S`, which reduces generics bloat.
 
-  - `Entry<K, V>` no longer has a type parameter `S`, which is just like
-    the standard `HashMap`'s entry.
+- `Entry<K, V>` no longer has a type parameter `S`, which is just like
+  the standard `HashMap`'s entry.
 
-  - Minimum Rust version requirement increased to Rust 1.18
+- Minimum Rust version requirement increased to Rust 1.18
 
-- 0.3.5
+## 0.3.5
 
-  - Documentation improvements
+- Documentation improvements
 
-- 0.3.4
+## 0.3.4
 
-  - The `.retain()` methods for `OrderMap` and `OrderSet` now
-    traverse the elements in order, and the retained elements **keep their order**
-  - Added new methods `.sort_by()`, `.sort_keys()` to `OrderMap` and
-    `.sort_by()`, `.sort()` to `OrderSet`. These methods allow you to
-    sort the maps in place efficiently.
+- The `.retain()` methods for `OrderMap` and `OrderSet` now
+  traverse the elements in order, and the retained elements **keep their order**
+- Added new methods `.sort_by()`, `.sort_keys()` to `OrderMap` and
+  `.sort_by()`, `.sort()` to `OrderSet`. These methods allow you to
+  sort the maps in place efficiently.
 
-- 0.3.3
+## 0.3.3
 
-  - Document insertion behaviour better by @lucab
-  - Updated dependences (no feature changes) by @ignatenkobrain
+- Document insertion behaviour better by @lucab
+- Updated dependences (no feature changes) by @ignatenkobrain
 
-- 0.3.2
+## 0.3.2
 
-  - Add `OrderSet` by @cuviper!
-  - `OrderMap::drain` is now (too) a double ended iterator.
+- Add `OrderSet` by @cuviper!
+- `OrderMap::drain` is now (too) a double ended iterator.
 
-- 0.3.1
+## 0.3.1
 
-  - In all ordermap iterators, forward the `collect` method to the underlying
-    iterator as well.
-  - Add crates.io categories.
+- In all ordermap iterators, forward the `collect` method to the underlying
+  iterator as well.
+- Add crates.io categories.
 
-- 0.3.0
+## 0.3.0
 
-  - The methods `get_pair`, `get_pair_index` were both replaced by
-    `get_full` (and the same for the mutable case).
-  - Method `swap_remove_pair` replaced by `swap_remove_full`.
-  - Add trait `MutableKeys` for opt-in mutable key access. Mutable key access
-    is only possible through the methods of this extension trait.
-  - Add new trait `Equivalent` for key equivalence. This extends the
-    `Borrow` trait mechanism for `OrderMap::get` in a backwards compatible
-    way, just some minor type inference related issues may become apparent.
-    See [#10] for more information.
-  - Implement `Extend<(&K, &V)>` by @xfix.
+- The methods `get_pair`, `get_pair_index` were both replaced by
+  `get_full` (and the same for the mutable case).
+- Method `swap_remove_pair` replaced by `swap_remove_full`.
+- Add trait `MutableKeys` for opt-in mutable key access. Mutable key access
+  is only possible through the methods of this extension trait.
+- Add new trait `Equivalent` for key equivalence. This extends the
+  `Borrow` trait mechanism for `OrderMap::get` in a backwards compatible
+  way, just some minor type inference related issues may become apparent.
+  See [#10] for more information.
+- Implement `Extend<(&K, &V)>` by @xfix.
 
-[#10]: https://github.com/bluss/ordermap/pull/10
+[#10]: https://github.com/indexmap-rs/indexmap/pull/10
 
-- 0.2.13
+## 0.2.13
 
-  - Fix deserialization to support custom hashers by @Techcable.
-  - Add methods `.index()` on the entry types by @garro95.
+- Fix deserialization to support custom hashers by @Techcable.
+- Add methods `.index()` on the entry types by @garro95.
 
-- 0.2.12
+## 0.2.12
 
-  - Add methods `.with_hasher()`, `.hasher()`.
+- Add methods `.with_hasher()`, `.hasher()`.
 
-- 0.2.11
+## 0.2.11
 
-  - Support `ExactSizeIterator` for the iterators. By @Binero.
-  - Use `Box<[Pos]>` internally, saving a word in the `OrderMap` struct.
-  - Serde support, with crate feature `"serde-1"`. By @xfix.
+- Support `ExactSizeIterator` for the iterators. By @Binero.
+- Use `Box<[Pos]>` internally, saving a word in the `OrderMap` struct.
+- Serde support, with crate feature `"serde-1"`. By @xfix.
 
-- 0.2.10
+## 0.2.10
 
-  - Add iterator `.drain(..)` by @stevej.
+- Add iterator `.drain(..)` by @stevej.
 
-- 0.2.9
+## 0.2.9
 
-  - Add method `.is_empty()` by @overvenus.
-  - Implement `PartialEq, Eq` by @overvenus.
-  - Add method `.sorted_by()`.
+- Add method `.is_empty()` by @overvenus.
+- Implement `PartialEq, Eq` by @overvenus.
+- Add method `.sorted_by()`.
 
-- 0.2.8
+## 0.2.8
 
-  - Add iterators `.values()` and `.values_mut()`.
-  - Fix compatibility with 32-bit platforms.
+- Add iterators `.values()` and `.values_mut()`.
+- Fix compatibility with 32-bit platforms.
 
-- 0.2.7
+## 0.2.7
 
-  - Add `.retain()`.
+- Add `.retain()`.
 
-- 0.2.6
+## 0.2.6
 
-  - Add `OccupiedEntry::remove_entry` and other minor entry methods,
-    so that it now has all the features of `HashMap`'s entries.
+- Add `OccupiedEntry::remove_entry` and other minor entry methods,
+  so that it now has all the features of `HashMap`'s entries.
 
-- 0.2.5
+## 0.2.5
 
-  - Improved `.pop()` slightly.
+- Improved `.pop()` slightly.
 
-- 0.2.4
+## 0.2.4
 
-  - Improved performance of `.insert()` ([#3]) by @pczarn.
+- Improved performance of `.insert()` ([#3]) by @pczarn.
 
-[#3]: https://github.com/bluss/ordermap/pull/3
+[#3]: https://github.com/indexmap-rs/indexmap/pull/3
 
-- 0.2.3
+## 0.2.3
 
-  - Generalize `Entry` for now, so that it works on hashmaps with non-default
-    hasher. However, there's a lingering compat issue since libstd `HashMap`
-    does not parameterize its entries by the hasher (`S` typarm).
-  - Special case some iterator methods like `.nth()`.
+- Generalize `Entry` for now, so that it works on hashmaps with non-default
+  hasher. However, there's a lingering compat issue since libstd `HashMap`
+  does not parameterize its entries by the hasher (`S` typarm).
+- Special case some iterator methods like `.nth()`.
 
-- 0.2.2
+## 0.2.2
 
-  - Disable the verbose `Debug` impl by default.
+- Disable the verbose `Debug` impl by default.
 
-- 0.2.1
+## 0.2.1
 
-  - Fix doc links and clarify docs.
+- Fix doc links and clarify docs.
 
-- 0.2.0
+## 0.2.0
 
-  - Add more `HashMap` methods & compat with its API.
-  - Experimental support for `.entry()` (the simplest parts of the API).
-  - Add `.reserve()` (placeholder impl).
-  - Add `.remove()` as synonym for `.swap_remove()`.
-  - Changed `.insert()` to swap value if the entry already exists, and
-    return `Option`.
-  - Experimental support as an *indexed* hash map! Added methods
-    `.get_index()`, `.get_index_mut()`, `.swap_remove_index()`,
-    `.get_pair_index()`, `.get_pair_index_mut()`.
+- Add more `HashMap` methods & compat with its API.
+- Experimental support for `.entry()` (the simplest parts of the API).
+- Add `.reserve()` (placeholder impl).
+- Add `.remove()` as synonym for `.swap_remove()`.
+- Changed `.insert()` to swap value if the entry already exists, and
+  return `Option`.
+- Experimental support as an *indexed* hash map! Added methods
+  `.get_index()`, `.get_index_mut()`, `.swap_remove_index()`,
+  `.get_pair_index()`, `.get_pair_index_mut()`.
 
-- 0.1.2
+## 0.1.2
 
-  - Implement the 32/32 split idea for `Pos` which improves cache utilization
-    and lookup performance.
+- Implement the 32/32 split idea for `Pos` which improves cache utilization
+  and lookup performance.
 
-- 0.1.1
+## 0.1.1
 
-  - Initial release.
+- Initial release.
diff --git a/third_party/rust/indexmap/build.rs b/third_party/rust/indexmap/build.rs
deleted file mode 100644
index 9f9fa054f8..0000000000
--- a/third_party/rust/indexmap/build.rs
+++ /dev/null
@@ -1,8 +0,0 @@
-fn main() {
-    // If "std" is explicitly requested, don't bother probing the target for it.
-    match std::env::var_os("CARGO_FEATURE_STD") {
-        Some(_) => autocfg::emit("has_std"),
-        None => autocfg::new().emit_sysroot_crate("std"),
-    }
-    autocfg::rerun_path("build.rs");
-}
diff --git a/third_party/rust/indexmap/src/arbitrary.rs b/third_party/rust/indexmap/src/arbitrary.rs
index 1347c8b54f..7798438c15 100644
--- a/third_party/rust/indexmap/src/arbitrary.rs
+++ b/third_party/rust/indexmap/src/arbitrary.rs
@@ -1,4 +1,5 @@
 #[cfg(feature = "arbitrary")]
+#[cfg_attr(docsrs, doc(cfg(feature = "arbitrary")))]
 mod impl_arbitrary {
     use crate::{IndexMap, IndexSet};
     use arbitrary::{Arbitrary, Result, Unstructured};
@@ -35,6 +36,7 @@ mod impl_arbitrary {
 }
 
 #[cfg(feature = "quickcheck")]
+#[cfg_attr(docsrs, doc(cfg(feature = "quickcheck")))]
 mod impl_quickcheck {
     use crate::{IndexMap, IndexSet};
     use alloc::boxed::Box;
diff --git a/third_party/rust/indexmap/src/borsh.rs b/third_party/rust/indexmap/src/borsh.rs
new file mode 100644
index 0000000000..c485bd5222
--- /dev/null
+++ b/third_party/rust/indexmap/src/borsh.rs
@@ -0,0 +1,122 @@
+#![cfg_attr(docsrs, doc(cfg(feature = "borsh")))]
+
+use alloc::vec::Vec;
+use core::hash::BuildHasher;
+use core::hash::Hash;
+use core::mem::size_of;
+
+use borsh::error::ERROR_ZST_FORBIDDEN;
+use borsh::io::{Error, ErrorKind, Read, Result, Write};
+use borsh::{BorshDeserialize, BorshSerialize};
+
+use crate::map::IndexMap;
+use crate::set::IndexSet;
+
+impl<K, V, S> BorshSerialize for IndexMap<K, V, S>
+where
+    K: BorshSerialize,
+    V: BorshSerialize,
+{
+    #[inline]
+    fn serialize<W: Write>(&self, writer: &mut W) -> Result<()> {
+        check_zst::<K>()?;
+
+        let iterator = self.iter();
+
+        u32::try_from(iterator.len())
+            .map_err(|_| ErrorKind::InvalidData)?
+            .serialize(writer)?;
+
+        for (key, value) in iterator {
+            key.serialize(writer)?;
+            value.serialize(writer)?;
+        }
+
+        Ok(())
+    }
+}
+
+impl<K, V, S> BorshDeserialize for IndexMap<K, V, S>
+where
+    K: BorshDeserialize + Eq + Hash,
+    V: BorshDeserialize,
+    S: BuildHasher + Default,
+{
+    #[inline]
+    fn deserialize_reader<R: Read>(reader: &mut R) -> Result<Self> {
+        check_zst::<K>()?;
+        let vec = <Vec<(K, V)>>::deserialize_reader(reader)?;
+        Ok(vec.into_iter().collect::<IndexMap<K, V, S>>())
+    }
+}
+
+impl<T, S> BorshSerialize for IndexSet<T, S>
+where
+    T: BorshSerialize,
+{
+    #[inline]
+    fn serialize<W: Write>(&self, writer: &mut W) -> Result<()> {
+        check_zst::<T>()?;
+
+        let iterator = self.iter();
+
+        u32::try_from(iterator.len())
+            .map_err(|_| ErrorKind::InvalidData)?
+            .serialize(writer)?;
+
+        for item in iterator {
+            item.serialize(writer)?;
+        }
+
+        Ok(())
+    }
+}
+
+impl<T, S> BorshDeserialize for IndexSet<T, S>
+where
+    T: BorshDeserialize + Eq + Hash,
+    S: BuildHasher + Default,
+{
+    #[inline]
+    fn deserialize_reader<R: Read>(reader: &mut R) -> Result<Self> {
+        check_zst::<T>()?;
+        let vec = <Vec<T>>::deserialize_reader(reader)?;
+        Ok(vec.into_iter().collect::<IndexSet<T, S>>())
+    }
+}
+
+fn check_zst<T>() -> Result<()> {
+    if size_of::<T>() == 0 {
+        return Err(Error::new(ErrorKind::InvalidData, ERROR_ZST_FORBIDDEN));
+    }
+    Ok(())
+}
+
+#[cfg(test)]
+mod borsh_tests {
+    use super::*;
+
+    #[test]
+    fn map_borsh_roundtrip() {
+        let original_map: IndexMap<i32, i32> = {
+            let mut map = IndexMap::new();
+            map.insert(1, 2);
+            map.insert(3, 4);
+            map.insert(5, 6);
+            map
+        };
+        let serialized_map = borsh::to_vec(&original_map).unwrap();
+        let deserialized_map: IndexMap<i32, i32> =
+            BorshDeserialize::try_from_slice(&serialized_map).unwrap();
+        assert_eq!(original_map, deserialized_map);
+    }
+
+    #[test]
+    fn set_borsh_roundtrip() {
+        let original_map: IndexSet<i32> = [1, 2, 3, 4, 5, 6].into_iter().collect();
+        let serialized_map = borsh::to_vec(&original_map).unwrap();
+        let deserialized_map: IndexSet<i32> =
+            BorshDeserialize::try_from_slice(&serialized_map).unwrap();
+        assert_eq!(original_map, deserialized_map);
+    }
+}
diff --git a/third_party/rust/indexmap/src/equivalent.rs b/third_party/rust/indexmap/src/equivalent.rs
deleted file mode 100644
index ad6635ffac..0000000000
--- a/third_party/rust/indexmap/src/equivalent.rs
+++ /dev/null
@@ -1,27 +0,0 @@
-use core::borrow::Borrow;
-
-/// Key equivalence trait.
-///
-/// This trait allows hash table lookup to be customized.
-/// It has one blanket implementation that uses the regular `Borrow` solution,
-/// just like `HashMap` and `BTreeMap` do, so that you can pass `&str` to lookup
-/// into a map with `String` keys and so on.
-///
-/// # Contract
-///
-/// The implementor **must** hash like `K`, if it is hashable.
-pub trait Equivalent<K: ?Sized> {
-    /// Compare self to `key` and return `true` if they are equal.
-    fn equivalent(&self, key: &K) -> bool;
-}
-
-impl<Q: ?Sized, K: ?Sized> Equivalent<K> for Q
-where
-    Q: Eq,
-    K: Borrow<Q>,
-{
-    #[inline]
-    fn equivalent(&self, key: &K) -> bool {
-        *self == *key.borrow()
-    }
-}
diff --git a/third_party/rust/indexmap/src/lib.rs b/third_party/rust/indexmap/src/lib.rs
index 6e94936124..7d88ffef08 100644
--- a/third_party/rust/indexmap/src/lib.rs
+++ b/third_party/rust/indexmap/src/lib.rs
@@ -1,7 +1,6 @@
 // We *mostly* avoid unsafe code, but `map::core::raw` allows it to use `RawTable` buckets.
 #![deny(unsafe_code)]
 #![warn(rust_2018_idioms)]
-#![doc(html_root_url = "https://docs.rs/indexmap/1/")]
 #![no_std]
 
 //! [`IndexMap`] is a hash table where the iteration order of the key-value
@@ -10,11 +9,7 @@
 //! [`IndexSet`] is a corresponding hash set using the same implementation and
 //! with similar properties.
 //!
-//! [`IndexMap`]: map/struct.IndexMap.html
-//! [`IndexSet`]: set/struct.IndexSet.html
-//!
-//!
-//! ### Feature Highlights
+//! ### Highlights
 //!
 //! [`IndexMap`] and [`IndexSet`] are drop-in compatible with the std `HashMap`
 //! and `HashSet`, but they also have some features of note:
@@ -24,11 +19,44 @@
 //! - The [`Equivalent`] trait, which offers more flexible equality definitions
 //!   between borrowed and owned versions of keys.
 //! - The [`MutableKeys`][map::MutableKeys] trait, which gives opt-in mutable
-//!   access to hash map keys.
+//!   access to map keys, and [`MutableValues`][set::MutableValues] for sets.
+//!
+//! ### Feature Flags
+//!
+//! To reduce the amount of compiled code in the crate by default, certain
+//! features are gated behind [feature flags]. These allow you to opt in to (or
+//! out of) functionality. Below is a list of the features available in this
+//! crate.
+//!
+//! * `std`: Enables features which require the Rust standard library. For more
+//!   information see the section on [`no_std`].
+//! * `rayon`: Enables parallel iteration and other parallel methods.
+//! * `serde`: Adds implementations for [`Serialize`] and [`Deserialize`]
+//!   to [`IndexMap`] and [`IndexSet`]. Alternative implementations for
+//!   (de)serializing [`IndexMap`] as an ordered sequence are available in the
+//!   [`map::serde_seq`] module.
+//! * `borsh`: Adds implementations for [`BorshSerialize`] and [`BorshDeserialize`]
+//!   to [`IndexMap`] and [`IndexSet`].
+//! * `arbitrary`: Adds implementations for the [`arbitrary::Arbitrary`] trait
+//!   to [`IndexMap`] and [`IndexSet`].
+//! * `quickcheck`: Adds implementations for the [`quickcheck::Arbitrary`] trait
+//!   to [`IndexMap`] and [`IndexSet`].
+//!
+//! _Note: only the `std` feature is enabled by default._
+//!
+//! [feature flags]: https://doc.rust-lang.org/cargo/reference/manifest.html#the-features-section
+//! [`no_std`]: #no-standard-library-targets
+//! [`Serialize`]: `::serde::Serialize`
+//! [`Deserialize`]: `::serde::Deserialize`
+//! [`BorshSerialize`]: `::borsh::BorshSerialize`
+//! [`BorshDeserialize`]: `::borsh::BorshDeserialize`
+//! [`arbitrary::Arbitrary`]: `::arbitrary::Arbitrary`
+//! [`quickcheck::Arbitrary`]: `::quickcheck::Arbitrary`
 //!
 //! ### Alternate Hashers
 //!
-//! [`IndexMap`] and [`IndexSet`] have a default hasher type `S = RandomState`,
+//! [`IndexMap`] and [`IndexSet`] have a default hasher type
+//! [`S = RandomState`][std::collections::hash_map::RandomState],
 //! just like the standard `HashMap` and `HashSet`, which is resistant to
 //! HashDoS attacks but not the most performant. Type aliases can make it easier
 //! to use alternate hashers:
@@ -53,33 +81,31 @@
 //!
 //! ### Rust Version
 //!
-//! This version of indexmap requires Rust 1.56 or later.
+//! This version of indexmap requires Rust 1.63 or later.
 //!
-//! The indexmap 1.x release series will use a carefully considered version
-//! upgrade policy, where in a later 1.x version, we will raise the minimum
+//! The indexmap 2.x release series will use a carefully considered version
+//! upgrade policy, where in a later 2.x version, we will raise the minimum
 //! required Rust version.
 //!
 //! ## No Standard Library Targets
 //!
-//! This crate supports being built without `std`, requiring
-//! `alloc` instead. This is enabled automatically when it is detected that
-//! `std` is not available. There is no crate feature to enable/disable to
-//! trigger this. It can be tested by building for a std-less target.
+//! This crate supports being built without `std`, requiring `alloc` instead.
+//! This is chosen by disabling the default "std" cargo feature, by adding
+//! `default-features = false` to your dependency specification.
 //!
 //! - Creating maps and sets using [`new`][IndexMap::new] and
-//! [`with_capacity`][IndexMap::with_capacity] is unavailable without `std`.  
-//!   Use methods [`IndexMap::default`][def],
-//!   [`with_hasher`][IndexMap::with_hasher],
+//! [`with_capacity`][IndexMap::with_capacity] is unavailable without `std`.
+//!   Use methods [`IndexMap::default`], [`with_hasher`][IndexMap::with_hasher],
 //!   [`with_capacity_and_hasher`][IndexMap::with_capacity_and_hasher] instead.
 //!   A no-std compatible hasher will be needed as well, for example
 //!   from the crate `twox-hash`.
 //! - Macros [`indexmap!`] and [`indexset!`] are unavailable without `std`.
-//!
-//! [def]: map/struct.IndexMap.html#impl-Default
+
+#![cfg_attr(docsrs, feature(doc_cfg))]
 
 extern crate alloc;
 
-#[cfg(has_std)]
+#[cfg(feature = "std")]
 #[macro_use]
 extern crate std;
 
@@ -88,12 +114,10 @@ use alloc::vec::{self, Vec};
 mod arbitrary;
 #[macro_use]
 mod macros;
-mod equivalent;
-mod mutable_keys;
+#[cfg(feature = "borsh")]
+mod borsh;
 #[cfg(feature = "serde")]
 mod serde;
-#[cfg(feature = "serde")]
-pub mod serde_seq;
 mod util;
 
 pub mod map;
@@ -107,9 +131,9 @@ mod rayon;
 #[cfg(feature = "rustc-rayon")]
 mod rustc;
 
-pub use crate::equivalent::Equivalent;
 pub use crate::map::IndexMap;
 pub use crate::set::IndexSet;
+pub use equivalent::Equivalent;
 
 // shared private items
 
@@ -192,3 +216,59 @@ trait Entries {
     where
         F: FnOnce(&mut [Self::Entry]);
 }
+
+/// The error type for [`try_reserve`][IndexMap::try_reserve] methods.
+#[derive(Clone, PartialEq, Eq, Debug)]
+pub struct TryReserveError {
+    kind: TryReserveErrorKind,
+}
+
+#[derive(Clone, PartialEq, Eq, Debug)]
+enum TryReserveErrorKind {
+    // The standard library's kind is currently opaque to us, otherwise we could unify this.
+    Std(alloc::collections::TryReserveError),
+    CapacityOverflow,
+    AllocError { layout: alloc::alloc::Layout },
+}
+
+// These are not `From` so we don't expose them in our public API.
+impl TryReserveError {
+    fn from_alloc(error: alloc::collections::TryReserveError) -> Self {
+        Self {
+            kind: TryReserveErrorKind::Std(error),
+        }
+    }
+
+    fn from_hashbrown(error: hashbrown::TryReserveError) -> Self {
+        Self {
+            kind: match error {
+                hashbrown::TryReserveError::CapacityOverflow => {
+                    TryReserveErrorKind::CapacityOverflow
+                }
+                hashbrown::TryReserveError::AllocError { layout } => {
+                    TryReserveErrorKind::AllocError { layout }
+                }
+            },
+        }
+    }
+}
+
+impl core::fmt::Display for TryReserveError {
+    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
+        let reason = match &self.kind {
+            TryReserveErrorKind::Std(e) => return core::fmt::Display::fmt(e, f),
+            TryReserveErrorKind::CapacityOverflow => {
+                " because the computed capacity exceeded the collection's maximum"
+            }
+            TryReserveErrorKind::AllocError { .. } => {
+                " because the memory allocator returned an error"
+            }
+        };
+        f.write_str("memory allocation failed")?;
+        f.write_str(reason)
+    }
+}
+
+#[cfg(feature = "std")]
+#[cfg_attr(docsrs, doc(cfg(feature = "std")))]
+impl std::error::Error for TryReserveError {}
diff --git a/third_party/rust/indexmap/src/macros.rs b/third_party/rust/indexmap/src/macros.rs
index ca26287be9..b347de22dd 100644
--- a/third_party/rust/indexmap/src/macros.rs
+++ b/third_party/rust/indexmap/src/macros.rs
@@ -1,6 +1,7 @@
-#[cfg(has_std)]
+#[cfg(feature = "std")]
+#[cfg_attr(docsrs, doc(cfg(feature = "std")))]
 #[macro_export]
-/// Create an `IndexMap` from a list of key-value pairs
+/// Create an [`IndexMap`][crate::IndexMap] from a list of key-value pairs
 ///
 /// ## Example
 ///
@@ -19,25 +20,25 @@
 /// assert_eq!(map.keys().next(), Some(&"a"));
 /// ```
 macro_rules! indexmap {
-    (@single $($x:tt)*) => (());
-    (@count $($rest:expr),*) => (<[()]>::len(&[$($crate::indexmap!(@single $rest)),*]));
-
     ($($key:expr => $value:expr,)+) => { $crate::indexmap!($($key => $value),+) };
     ($($key:expr => $value:expr),*) => {
         {
-            let _cap = $crate::indexmap!(@count $($key),*);
-            let mut _map = $crate::IndexMap::with_capacity(_cap);
+            // Note: `stringify!($key)` is just here to consume the repetition,
+            // but we throw away that string literal during constant evaluation.
+            const CAP: usize = <[()]>::len(&[$({ stringify!($key); }),*]);
+            let mut map = $crate::IndexMap::with_capacity(CAP);
             $(
-                _map.insert($key, $value);
+                map.insert($key, $value);
             )*
-            _map
+            map
         }
     };
 }
 
-#[cfg(has_std)]
+#[cfg(feature = "std")]
+#[cfg_attr(docsrs, doc(cfg(feature = "std")))]
 #[macro_export]
-/// Create an `IndexSet` from a list of values
+/// Create an [`IndexSet`][crate::IndexSet] from a list of values
 ///
 /// ## Example
 ///
@@ -56,18 +57,17 @@ macro_rules! indexmap {
 /// assert_eq!(set.iter().next(), Some(&"a"));
 /// ```
 macro_rules! indexset {
-    (@single $($x:tt)*) => (());
-    (@count $($rest:expr),*) => (<[()]>::len(&[$($crate::indexset!(@single $rest)),*]));
-
     ($($value:expr,)+) => { $crate::indexset!($($value),+) };
     ($($value:expr),*) => {
         {
-            let _cap = $crate::indexset!(@count $($value),*);
-            let mut _set = $crate::IndexSet::with_capacity(_cap);
+            // Note: `stringify!($value)` is just here to consume the repetition,
+            // but we throw away that string literal during constant evaluation.
+            const CAP: usize = <[()]>::len(&[$({ stringify!($value); }),*]);
+            let mut set = $crate::IndexSet::with_capacity(CAP);
             $(
-                _set.insert($value);
+                set.insert($value);
             )*
-            _set
+            set
         }
     };
 }
diff --git a/third_party/rust/indexmap/src/map.rs b/third_party/rust/indexmap/src/map.rs
index d39448d06d..82824c9002 100644
--- a/third_party/rust/indexmap/src/map.rs
+++ b/third_party/rust/indexmap/src/map.rs
@@ -1,36 +1,50 @@
-//! `IndexMap` is a hash table where the iteration order of the key-value
+//! [`IndexMap`] is a hash table where the iteration order of the key-value
 //! pairs is independent of the hash values of the keys.
 
 mod core;
+mod iter;
+mod mutable;
+mod slice;
 
-pub use crate::mutable_keys::MutableKeys;
+#[cfg(feature = "serde")]
+#[cfg_attr(docsrs, doc(cfg(feature = "serde")))]
+pub mod serde_seq;
+
+#[cfg(test)]
+mod tests;
+
+pub use self::core::raw_entry_v1::{self, RawEntryApiV1};
+pub use self::core::{Entry, IndexedEntry, OccupiedEntry, VacantEntry};
+pub use self::iter::{
+    Drain, IntoIter, IntoKeys, IntoValues, Iter, IterMut, Keys, Splice, Values, ValuesMut,
+};
+pub use self::mutable::MutableKeys;
+pub use self::slice::Slice;
 
 #[cfg(feature = "rayon")]
 pub use crate::rayon::map as rayon;
 
-use crate::vec::{self, Vec};
 use ::core::cmp::Ordering;
 use ::core::fmt;
 use ::core::hash::{BuildHasher, Hash, Hasher};
-use ::core::iter::FusedIterator;
+use ::core::mem;
 use ::core::ops::{Index, IndexMut, RangeBounds};
-use ::core::slice::{Iter as SliceIter, IterMut as SliceIterMut};
+use alloc::boxed::Box;
+use alloc::vec::Vec;
 
-#[cfg(has_std)]
+#[cfg(feature = "std")]
 use std::collections::hash_map::RandomState;
 
 use self::core::IndexMapCore;
-use crate::equivalent::Equivalent;
-use crate::util::third;
-use crate::{Bucket, Entries, HashValue};
-
-pub use self::core::{Entry, OccupiedEntry, VacantEntry};
+use crate::util::{third, try_simplify_range};
+use crate::{Bucket, Entries, Equivalent, HashValue, TryReserveError};
 
 /// A hash table where the iteration order of the key-value pairs is independent
 /// of the hash values of the keys.
 ///
-/// The interface is closely compatible with the standard `HashMap`, but also
-/// has additional features.
+/// The interface is closely compatible with the standard
+/// [`HashMap`][std::collections::HashMap],
+/// but also has additional features.
 ///
 /// # Order
 ///
@@ -41,7 +55,8 @@ pub use self::core::{Entry, OccupiedEntry, VacantEntry};
 /// All iterators traverse the map in *the order*.
 ///
 /// The insertion order is preserved, with **notable exceptions** like the
-/// `.remove()` or `.swap_remove()` methods. Methods such as `.sort_by()` of
+/// [`.remove()`][Self::remove] or [`.swap_remove()`][Self::swap_remove] methods.
+/// Methods such as [`.sort_by()`][Self::sort_by] of
 /// course result in a new order, depending on the sorting order.
 ///
 /// # Indices
@@ -67,12 +82,12 @@ pub use self::core::{Entry, OccupiedEntry, VacantEntry};
 /// assert_eq!(letters[&'u'], 1);
 /// assert_eq!(letters.get(&'y'), None);
 /// ```
-#[cfg(has_std)]
+#[cfg(feature = "std")]
 pub struct IndexMap<K, V, S = RandomState> {
     pub(crate) core: IndexMapCore<K, V>,
     hash_builder: S,
 }
-#[cfg(not(has_std))]
+#[cfg(not(feature = "std"))]
 pub struct IndexMap<K, V, S> {
     pub(crate) core: IndexMapCore<K, V>,
     hash_builder: S,
@@ -128,19 +143,22 @@ where
     K: fmt::Debug,
     V: fmt::Debug,
 {
+    #[cfg(not(feature = "test_debug"))]
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        if cfg!(not(feature = "test_debug")) {
-            f.debug_map().entries(self.iter()).finish()
-        } else {
-            // Let the inner `IndexMapCore` print all of its details
-            f.debug_struct("IndexMap")
-                .field("core", &self.core)
-                .finish()
-        }
+        f.debug_map().entries(self.iter()).finish()
+    }
+
+    #[cfg(feature = "test_debug")]
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        // Let the inner `IndexMapCore` print all of its details
+        f.debug_struct("IndexMap")
+            .field("core", &self.core)
+            .finish()
     }
 }
 
-#[cfg(has_std)]
+#[cfg(feature = "std")]
+#[cfg_attr(docsrs, doc(cfg(feature = "std")))]
 impl<K, V> IndexMap<K, V> {
     /// Create a new map. (Does not allocate.)
     #[inline]
@@ -186,6 +204,11 @@ impl<K, V, S> IndexMap<K, V, S> {
         }
     }
 
+    /// Return the number of elements the map can hold without reallocating.
+    ///
+    /// This number is a lower bound; the map might be able to hold more,
+    /// but is guaranteed to be able to hold at least this many.
+    ///
     /// Computes in **O(1)** time.
     pub fn capacity(&self) -> usize {
         self.core.capacity()
@@ -214,52 +237,38 @@ impl<K, V, S> IndexMap<K, V, S> {
 
     /// Return an iterator over the key-value pairs of the map, in their order
     pub fn iter(&self) -> Iter<'_, K, V> {
-        Iter {
-            iter: self.as_entries().iter(),
-        }
+        Iter::new(self.as_entries())
     }
 
     /// Return an iterator over the key-value pairs of the map, in their order
     pub fn iter_mut(&mut self) -> IterMut<'_, K, V> {
-        IterMut {
-            iter: self.as_entries_mut().iter_mut(),
-        }
+        IterMut::new(self.as_entries_mut())
     }
 
     /// Return an iterator over the keys of the map, in their order
     pub fn keys(&self) -> Keys<'_, K, V> {
-        Keys {
-            iter: self.as_entries().iter(),
-        }
+        Keys::new(self.as_entries())
     }
 
     /// Return an owning iterator over the keys of the map, in their order
     pub fn into_keys(self) -> IntoKeys<K, V> {
-        IntoKeys {
-            iter: self.into_entries().into_iter(),
-        }
+        IntoKeys::new(self.into_entries())
     }
 
     /// Return an iterator over the values of the map, in their order
     pub fn values(&self) -> Values<'_, K, V> {
-        Values {
-            iter: self.as_entries().iter(),
-        }
+        Values::new(self.as_entries())
     }
 
     /// Return an iterator over mutable references to the values of the map,
     /// in their order
     pub fn values_mut(&mut self) -> ValuesMut<'_, K, V> {
-        ValuesMut {
-            iter: self.as_entries_mut().iter_mut(),
-        }
+        ValuesMut::new(self.as_entries_mut())
     }
 
     /// Return an owning iterator over the values of the map, in their order
     pub fn into_values(self) -> IntoValues<K, V> {
-        IntoValues {
-            iter: self.into_entries().into_iter(),
-        }
+        IntoValues::new(self.into_entries())
     }
 
     /// Remove all key-value pairs in the map, while preserving its capacity.
@@ -279,7 +288,7 @@ impl<K, V, S> IndexMap<K, V, S> {
     /// Clears the `IndexMap` in the given index range, returning those
     /// key-value pairs as a drain iterator.
     ///
-    /// The range may be any type that implements `RangeBounds<usize>`,
+    /// The range may be any type that implements [`RangeBounds<usize>`],
     /// including all of the `std::ops::Range*` types, or even a tuple pair of
     /// `Bound` start and end values. To drain the map entirely, use `RangeFull`
     /// like `map.drain(..)`.
@@ -293,9 +302,7 @@ impl<K, V, S> IndexMap<K, V, S> {
     where
         R: RangeBounds<usize>,
     {
-        Drain {
-            iter: self.core.drain(range),
-        }
+        Drain::new(self.core.drain(range))
     }
 
     /// Splits the collection into two at the given index.
@@ -314,13 +321,7 @@ impl<K, V, S> IndexMap<K, V, S> {
             hash_builder: self.hash_builder.clone(),
         }
     }
-}
 
-impl<K, V, S> IndexMap<K, V, S>
-where
-    K: Hash + Eq,
-    S: BuildHasher,
-{
     /// Reserve capacity for `additional` more key-value pairs.
     ///
     /// Computes in **O(n)** time.
@@ -328,6 +329,37 @@ where
         self.core.reserve(additional);
     }
 
+    /// Reserve capacity for `additional` more key-value pairs, without over-allocating.
+    ///
+    /// Unlike `reserve`, this does not deliberately over-allocate the entry capacity to avoid
+    /// frequent re-allocations. However, the underlying data structures may still have internal
+    /// capacity requirements, and the allocator itself may give more space than requested, so this
+    /// cannot be relied upon to be precisely minimal.
+    ///
+    /// Computes in **O(n)** time.
+    pub fn reserve_exact(&mut self, additional: usize) {
+        self.core.reserve_exact(additional);
+    }
+
+    /// Try to reserve capacity for `additional` more key-value pairs.
+    ///
+    /// Computes in **O(n)** time.
+    pub fn try_reserve(&mut self, additional: usize) -> Result<(), TryReserveError> {
+        self.core.try_reserve(additional)
+    }
+
+    /// Try to reserve capacity for `additional` more key-value pairs, without over-allocating.
+    ///
+    /// Unlike `try_reserve`, this does not deliberately over-allocate the entry capacity to avoid
+    /// frequent re-allocations. However, the underlying data structures may still have internal
+    /// capacity requirements, and the allocator itself may give more space than requested, so this
+    /// cannot be relied upon to be precisely minimal.
+    ///
+    /// Computes in **O(n)** time.
+    pub fn try_reserve_exact(&mut self, additional: usize) -> Result<(), TryReserveError> {
+        self.core.try_reserve_exact(additional)
+    }
+
     /// Shrink the capacity of the map as much as possible.
     ///
     /// Computes in **O(n)** time.
@@ -341,26 +373,27 @@ where
     pub fn shrink_to(&mut self, min_capacity: usize) {
         self.core.shrink_to(min_capacity);
     }
+}
 
-    fn hash<Q: ?Sized + Hash>(&self, key: &Q) -> HashValue {
-        let mut h = self.hash_builder.build_hasher();
-        key.hash(&mut h);
-        HashValue(h.finish() as usize)
-    }
-
+impl<K, V, S> IndexMap<K, V, S>
+where
+    K: Hash + Eq,
+    S: BuildHasher,
+{
     /// Insert a key-value pair in the map.
     ///
     /// If an equivalent key already exists in the map: the key remains and
     /// retains in its place in the order, its corresponding value is updated
-    /// with `value` and the older value is returned inside `Some(_)`.
+    /// with `value`, and the older value is returned inside `Some(_)`.
     ///
     /// If no equivalent key existed in the map: the new key-value pair is
     /// inserted, last in order, and `None` is returned.
     ///
     /// Computes in **O(1)** time (amortized average).
     ///
-    /// See also [`entry`](#method.entry) if you you want to insert *or* modify
-    /// or if you need to get the index of the corresponding key-value pair.
+    /// See also [`entry`][Self::entry] if you want to insert *or* modify,
+    /// or [`insert_full`][Self::insert_full] if you need to get the index of
+    /// the corresponding key-value pair.
     pub fn insert(&mut self, key: K, value: V) -> Option<V> {
         self.insert_full(key, value).1
     }
@@ -369,20 +402,77 @@ where
     ///
     /// If an equivalent key already exists in the map: the key remains and
     /// retains in its place in the order, its corresponding value is updated
-    /// with `value` and the older value is returned inside `(index, Some(_))`.
+    /// with `value`, and the older value is returned inside `(index, Some(_))`.
     ///
     /// If no equivalent key existed in the map: the new key-value pair is
     /// inserted, last in order, and `(index, None)` is returned.
     ///
     /// Computes in **O(1)** time (amortized average).
     ///
-    /// See also [`entry`](#method.entry) if you you want to insert *or* modify
-    /// or if you need to get the index of the corresponding key-value pair.
+    /// See also [`entry`][Self::entry] if you want to insert *or* modify.
     pub fn insert_full(&mut self, key: K, value: V) -> (usize, Option<V>) {
         let hash = self.hash(&key);
         self.core.insert_full(hash, key, value)
     }
 
+    /// Insert a key-value pair in the map at its ordered position among sorted keys.
+    ///
+    /// This is equivalent to finding the position with
+    /// [`binary_search_keys`][Self::binary_search_keys], then either updating
+    /// it or calling [`shift_insert`][Self::shift_insert] for a new key.
+    ///
+    /// If the sorted key is found in the map, its corresponding value is
+    /// updated with `value`, and the older value is returned inside
+    /// `(index, Some(_))`. Otherwise, the new key-value pair is inserted at
+    /// the sorted position, and `(index, None)` is returned.
+    ///
+    /// If the existing keys are **not** already sorted, then the insertion
+    /// index is unspecified (like [`slice::binary_search`]), but the key-value
+    /// pair is moved to or inserted at that position regardless.
+    ///
+    /// Computes in **O(n)** time (average). Instead of repeating calls to
+    /// `insert_sorted`, it may be faster to call batched [`insert`][Self::insert]
+    /// or [`extend`][Self::extend] and only call [`sort_keys`][Self::sort_keys]
+    /// or [`sort_unstable_keys`][Self::sort_unstable_keys] once.
+    pub fn insert_sorted(&mut self, key: K, value: V) -> (usize, Option<V>)
+    where
+        K: Ord,
+    {
+        match self.binary_search_keys(&key) {
+            Ok(i) => (i, Some(mem::replace(&mut self[i], value))),
+            Err(i) => (i, self.shift_insert(i, key, value)),
+        }
+    }
+
+    /// Insert a key-value pair in the map at the given index.
+    ///
+    /// If an equivalent key already exists in the map: the key remains and
+    /// is moved to the new position in the map, its corresponding value is updated
+    /// with `value`, and the older value is returned inside `Some(_)`.
+    ///
+    /// If no equivalent key existed in the map: the new key-value pair is
+    /// inserted at the given index, and `None` is returned.
+    ///
+    /// ***Panics*** if `index` is out of bounds.
+    ///
+    /// Computes in **O(n)** time (average).
+    ///
+    /// See also [`entry`][Self::entry] if you want to insert *or* modify,
+    /// perhaps only using the index for new entries with [`VacantEntry::shift_insert`].
+    pub fn shift_insert(&mut self, index: usize, key: K, value: V) -> Option<V> {
+        match self.entry(key) {
+            Entry::Occupied(mut entry) => {
+                let old = mem::replace(entry.get_mut(), value);
+                entry.move_index(index);
+                Some(old)
+            }
+            Entry::Vacant(entry) => {
+                entry.shift_insert(index, value);
+                None
+            }
+        }
+    }
+
     /// Get the given key’s corresponding entry in the map for insertion and/or
     /// in-place manipulation.
     ///
@@ -392,12 +482,61 @@ where
         self.core.entry(hash, key)
     }
 
+    /// Creates a splicing iterator that replaces the specified range in the map
+    /// with the given `replace_with` key-value iterator and yields the removed
+    /// items. `replace_with` does not need to be the same length as `range`.
+    ///
+    /// The `range` is removed even if the iterator is not consumed until the
+    /// end. It is unspecified how many elements are removed from the map if the
+    /// `Splice` value is leaked.
+    ///
+    /// The input iterator `replace_with` is only consumed when the `Splice`
+    /// value is dropped. If a key from the iterator matches an existing entry
+    /// in the map (outside of `range`), then the value will be updated in that
+    /// position. Otherwise, the new key-value pair will be inserted in the
+    /// replaced `range`.
+    ///
+    /// ***Panics*** if the starting point is greater than the end point or if
+    /// the end point is greater than the length of the map.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use indexmap::IndexMap;
+    ///
+    /// let mut map = IndexMap::from([(0, '_'), (1, 'a'), (2, 'b'), (3, 'c'), (4, 'd')]);
+    /// let new = [(5, 'E'), (4, 'D'), (3, 'C'), (2, 'B'), (1, 'A')];
+    /// let removed: Vec<_> = map.splice(2..4, new).collect();
+    ///
+    /// // 1 and 4 got new values, while 5, 3, and 2 were newly inserted.
+    /// assert!(map.into_iter().eq([(0, '_'), (1, 'A'), (5, 'E'), (3, 'C'), (2, 'B'), (4, 'D')]));
+    /// assert_eq!(removed, &[(2, 'b'), (3, 'c')]);
+    /// ```
+    pub fn splice<R, I>(&mut self, range: R, replace_with: I) -> Splice<'_, I::IntoIter, K, V, S>
+    where
+        R: RangeBounds<usize>,
+        I: IntoIterator<Item = (K, V)>,
+    {
+        Splice::new(self, range, replace_with.into_iter())
+    }
+}
+
+impl<K, V, S> IndexMap<K, V, S>
+where
+    S: BuildHasher,
+{
+    pub(crate) fn hash<Q: ?Sized + Hash>(&self, key: &Q) -> HashValue {
+        let mut h = self.hash_builder.build_hasher();
+        key.hash(&mut h);
+        HashValue(h.finish() as usize)
+    }
+
     /// Return `true` if an equivalent to `key` exists in the map.
     ///
     /// Computes in **O(1)** time (average).
-    pub fn contains_key<Q: ?Sized>(&self, key: &Q) -> bool
+    pub fn contains_key<Q>(&self, key: &Q) -> bool
     where
-        Q: Hash + Equivalent<K>,
+        Q: ?Sized + Hash + Equivalent<K>,
     {
         self.get_index_of(key).is_some()
     }
@@ -406,9 +545,9 @@ where
     /// else `None`.
     ///
     /// Computes in **O(1)** time (average).
-    pub fn get<Q: ?Sized>(&self, key: &Q) -> Option<&V>
+    pub fn get<Q>(&self, key: &Q) -> Option<&V>
     where
-        Q: Hash + Equivalent<K>,
+        Q: ?Sized + Hash + Equivalent<K>,
     {
         if let Some(i) = self.get_index_of(key) {
             let entry = &self.as_entries()[i];
@@ -422,9 +561,9 @@ where
     /// if it is present, else `None`.
     ///
     /// Computes in **O(1)** time (average).
-    pub fn get_key_value<Q: ?Sized>(&self, key: &Q) -> Option<(&K, &V)>
+    pub fn get_key_value<Q>(&self, key: &Q) -> Option<(&K, &V)>
     where
-        Q: Hash + Equivalent<K>,
+        Q: ?Sized + Hash + Equivalent<K>,
     {
         if let Some(i) = self.get_index_of(key) {
             let entry = &self.as_entries()[i];
@@ -435,9 +574,9 @@ where
     }
 
     /// Return item index, key and value
-    pub fn get_full<Q: ?Sized>(&self, key: &Q) -> Option<(usize, &K, &V)>
+    pub fn get_full<Q>(&self, key: &Q) -> Option<(usize, &K, &V)>
     where
-        Q: Hash + Equivalent<K>,
+        Q: ?Sized + Hash + Equivalent<K>,
     {
         if let Some(i) = self.get_index_of(key) {
             let entry = &self.as_entries()[i];
@@ -450,21 +589,23 @@ where
     /// Return item index, if it exists in the map
     ///
     /// Computes in **O(1)** time (average).
-    pub fn get_index_of<Q: ?Sized>(&self, key: &Q) -> Option<usize>
+    pub fn get_index_of<Q>(&self, key: &Q) -> Option<usize>
     where
-        Q: Hash + Equivalent<K>,
+        Q: ?Sized + Hash + Equivalent<K>,
     {
-        if self.is_empty() {
-            None
-        } else {
-            let hash = self.hash(key);
-            self.core.get_index_of(hash, key)
+        match self.as_entries() {
+            [] => None,
+            [x] => key.equivalent(&x.key).then_some(0),
+            _ => {
+                let hash = self.hash(key);
+                self.core.get_index_of(hash, key)
+            }
         }
     }
 
-    pub fn get_mut<Q: ?Sized>(&mut self, key: &Q) -> Option<&mut V>
+    pub fn get_mut<Q>(&mut self, key: &Q) -> Option<&mut V>
     where
-        Q: Hash + Equivalent<K>,
+        Q: ?Sized + Hash + Equivalent<K>,
     {
         if let Some(i) = self.get_index_of(key) {
             let entry = &mut self.as_entries_mut()[i];
@@ -474,9 +615,9 @@ where
         }
     }
 
-    pub fn get_full_mut<Q: ?Sized>(&mut self, key: &Q) -> Option<(usize, &K, &mut V)>
+    pub fn get_full_mut<Q>(&mut self, key: &Q) -> Option<(usize, &K, &mut V)>
     where
-        Q: Hash + Equivalent<K>,
+        Q: ?Sized + Hash + Equivalent<K>,
     {
         if let Some(i) = self.get_index_of(key) {
             let entry = &mut self.as_entries_mut()[i];
@@ -486,46 +627,33 @@ where
         }
     }
 
-    pub(crate) fn get_full_mut2_impl<Q: ?Sized>(
-        &mut self,
-        key: &Q,
-    ) -> Option<(usize, &mut K, &mut V)>
-    where
-        Q: Hash + Equivalent<K>,
-    {
-        if let Some(i) = self.get_index_of(key) {
-            let entry = &mut self.as_entries_mut()[i];
-            Some((i, &mut entry.key, &mut entry.value))
-        } else {
-            None
-        }
-    }
-
     /// Remove the key-value pair equivalent to `key` and return
     /// its value.
     ///
-    /// **NOTE:** This is equivalent to `.swap_remove(key)`, if you need to
-    /// preserve the order of the keys in the map, use `.shift_remove(key)`
-    /// instead.
-    ///
-    /// Computes in **O(1)** time (average).
-    pub fn remove<Q: ?Sized>(&mut self, key: &Q) -> Option<V>
+    /// **NOTE:** This is equivalent to [`.swap_remove(key)`][Self::swap_remove], replacing this
+    /// entry's position with the last element, and it is deprecated in favor of calling that
+    /// explicitly. If you need to preserve the relative order of the keys in the map, use
+    /// [`.shift_remove(key)`][Self::shift_remove] instead.
+    #[deprecated(note = "`remove` disrupts the map order -- \
+        use `swap_remove` or `shift_remove` for explicit behavior.")]
+    pub fn remove<Q>(&mut self, key: &Q) -> Option<V>
     where
-        Q: Hash + Equivalent<K>,
+        Q: ?Sized + Hash + Equivalent<K>,
     {
         self.swap_remove(key)
     }
 
     /// Remove and return the key-value pair equivalent to `key`.
     ///
-    /// **NOTE:** This is equivalent to `.swap_remove_entry(key)`, if you need to
-    /// preserve the order of the keys in the map, use `.shift_remove_entry(key)`
-    /// instead.
-    ///
-    /// Computes in **O(1)** time (average).
-    pub fn remove_entry<Q: ?Sized>(&mut self, key: &Q) -> Option<(K, V)>
+    /// **NOTE:** This is equivalent to [`.swap_remove_entry(key)`][Self::swap_remove_entry],
+    /// replacing this entry's position with the last element, and it is deprecated in favor of
+    /// calling that explicitly. If you need to preserve the relative order of the keys in the map,
+    /// use [`.shift_remove_entry(key)`][Self::shift_remove_entry] instead.
+    #[deprecated(note = "`remove_entry` disrupts the map order -- \
+        use `swap_remove_entry` or `shift_remove_entry` for explicit behavior.")]
+    pub fn remove_entry<Q>(&mut self, key: &Q) -> Option<(K, V)>
     where
-        Q: Hash + Equivalent<K>,
+        Q: ?Sized + Hash + Equivalent<K>,
     {
         self.swap_remove_entry(key)
     }
@@ -533,32 +661,32 @@ where
     /// Remove the key-value pair equivalent to `key` and return
     /// its value.
     ///
-    /// Like `Vec::swap_remove`, the pair is removed by swapping it with the
+    /// Like [`Vec::swap_remove`], the pair is removed by swapping it with the
     /// last element of the map and popping it off. **This perturbs
     /// the position of what used to be the last element!**
     ///
     /// Return `None` if `key` is not in map.
     ///
     /// Computes in **O(1)** time (average).
-    pub fn swap_remove<Q: ?Sized>(&mut self, key: &Q) -> Option<V>
+    pub fn swap_remove<Q>(&mut self, key: &Q) -> Option<V>
     where
-        Q: Hash + Equivalent<K>,
+        Q: ?Sized + Hash + Equivalent<K>,
     {
         self.swap_remove_full(key).map(third)
     }
 
     /// Remove and return the key-value pair equivalent to `key`.
     ///
-    /// Like `Vec::swap_remove`, the pair is removed by swapping it with the
+    /// Like [`Vec::swap_remove`], the pair is removed by swapping it with the
     /// last element of the map and popping it off. **This perturbs
     /// the position of what used to be the last element!**
     ///
     /// Return `None` if `key` is not in map.
     ///
     /// Computes in **O(1)** time (average).
-    pub fn swap_remove_entry<Q: ?Sized>(&mut self, key: &Q) -> Option<(K, V)>
+    pub fn swap_remove_entry<Q>(&mut self, key: &Q) -> Option<(K, V)>
     where
-        Q: Hash + Equivalent<K>,
+        Q: ?Sized + Hash + Equivalent<K>,
     {
         match self.swap_remove_full(key) {
             Some((_, key, value)) => Some((key, value)),
@@ -569,53 +697,59 @@ where
     /// Remove the key-value pair equivalent to `key` and return it and
     /// the index it had.
     ///
-    /// Like `Vec::swap_remove`, the pair is removed by swapping it with the
+    /// Like [`Vec::swap_remove`], the pair is removed by swapping it with the
     /// last element of the map and popping it off. **This perturbs
     /// the position of what used to be the last element!**
     ///
     /// Return `None` if `key` is not in map.
     ///
     /// Computes in **O(1)** time (average).
-    pub fn swap_remove_full<Q: ?Sized>(&mut self, key: &Q) -> Option<(usize, K, V)>
+    pub fn swap_remove_full<Q>(&mut self, key: &Q) -> Option<(usize, K, V)>
     where
-        Q: Hash + Equivalent<K>,
+        Q: ?Sized + Hash + Equivalent<K>,
     {
-        if self.is_empty() {
-            return None;
+        match self.as_entries() {
+            [x] if key.equivalent(&x.key) => {
+                let (k, v) = self.core.pop()?;
+                Some((0, k, v))
+            }
+            [_] | [] => None,
+            _ => {
+                let hash = self.hash(key);
+                self.core.swap_remove_full(hash, key)
+            }
         }
-        let hash = self.hash(key);
-        self.core.swap_remove_full(hash, key)
     }
 
     /// Remove the key-value pair equivalent to `key` and return
     /// its value.
     ///
-    /// Like `Vec::remove`, the pair is removed by shifting all of the
+    /// Like [`Vec::remove`], the pair is removed by shifting all of the
     /// elements that follow it, preserving their relative order.
     /// **This perturbs the index of all of those elements!**
     ///
     /// Return `None` if `key` is not in map.
     ///
     /// Computes in **O(n)** time (average).
-    pub fn shift_remove<Q: ?Sized>(&mut self, key: &Q) -> Option<V>
+    pub fn shift_remove<Q>(&mut self, key: &Q) -> Option<V>
     where
-        Q: Hash + Equivalent<K>,
+        Q: ?Sized + Hash + Equivalent<K>,
     {
         self.shift_remove_full(key).map(third)
     }
 
     /// Remove and return the key-value pair equivalent to `key`.
     ///
-    /// Like `Vec::remove`, the pair is removed by shifting all of the
+    /// Like [`Vec::remove`], the pair is removed by shifting all of the
     /// elements that follow it, preserving their relative order.
     /// **This perturbs the index of all of those elements!**
     ///
     /// Return `None` if `key` is not in map.
     ///
     /// Computes in **O(n)** time (average).
-    pub fn shift_remove_entry<Q: ?Sized>(&mut self, key: &Q) -> Option<(K, V)>
+    pub fn shift_remove_entry<Q>(&mut self, key: &Q) -> Option<(K, V)>
     where
-        Q: Hash + Equivalent<K>,
+        Q: ?Sized + Hash + Equivalent<K>,
     {
         match self.shift_remove_full(key) {
             Some((_, key, value)) => Some((key, value)),
@@ -626,24 +760,32 @@ where
     /// Remove the key-value pair equivalent to `key` and return it and
     /// the index it had.
     ///
-    /// Like `Vec::remove`, the pair is removed by shifting all of the
+    /// Like [`Vec::remove`], the pair is removed by shifting all of the
     /// elements that follow it, preserving their relative order.
     /// **This perturbs the index of all of those elements!**
     ///
     /// Return `None` if `key` is not in map.
     ///
     /// Computes in **O(n)** time (average).
-    pub fn shift_remove_full<Q: ?Sized>(&mut self, key: &Q) -> Option<(usize, K, V)>
+    pub fn shift_remove_full<Q>(&mut self, key: &Q) -> Option<(usize, K, V)>
     where
-        Q: Hash + Equivalent<K>,
+        Q: ?Sized + Hash + Equivalent<K>,
     {
-        if self.is_empty() {
-            return None;
+        match self.as_entries() {
+            [x] if key.equivalent(&x.key) => {
+                let (k, v) = self.core.pop()?;
+                Some((0, k, v))
+            }
+            [_] | [] => None,
+            _ => {
+                let hash = self.hash(key);
+                self.core.shift_remove_full(hash, key)
+            }
         }
-        let hash = self.hash(key);
-        self.core.shift_remove_full(hash, key)
     }
+}
 
+impl<K, V, S> IndexMap<K, V, S> {
     /// Remove the last key-value pair
     ///
     /// This preserves the order of the remaining elements.
@@ -667,15 +809,12 @@ where
         self.core.retain_in_order(move |k, v| keep(k, v));
     }
 
-    pub(crate) fn retain_mut<F>(&mut self, keep: F)
-    where
-        F: FnMut(&mut K, &mut V) -> bool,
-    {
-        self.core.retain_in_order(keep);
-    }
-
     /// Sort the map’s key-value pairs by the default ordering of the keys.
     ///
+    /// This is a stable sort -- but equivalent keys should not normally coexist in
+    /// a map at all, so [`sort_unstable_keys`][Self::sort_unstable_keys] is preferred
+    /// because it is generally faster and doesn't allocate auxiliary memory.
+    ///
     /// See [`sort_by`](Self::sort_by) for details.
     pub fn sort_keys(&mut self)
     where
@@ -713,9 +852,7 @@ where
     {
         let mut entries = self.into_entries();
         entries.sort_by(move |a, b| cmp(&a.key, &a.value, &b.key, &b.value));
-        IntoIter {
-            iter: entries.into_iter(),
-        }
+        IntoIter::new(entries)
     }
 
     /// Sort the map's key-value pairs by the default ordering of the keys, but
@@ -759,9 +896,82 @@ where
     {
         let mut entries = self.into_entries();
         entries.sort_unstable_by(move |a, b| cmp(&a.key, &a.value, &b.key, &b.value));
-        IntoIter {
-            iter: entries.into_iter(),
-        }
+        IntoIter::new(entries)
+    }
+
+    /// Sort the map’s key-value pairs in place using a sort-key extraction function.
+    ///
+    /// During sorting, the function is called at most once per entry, by using temporary storage
+    /// to remember the results of its evaluation. The order of calls to the function is
+    /// unspecified and may change between versions of `indexmap` or the standard library.
+    ///
+    /// Computes in **O(m n + n log n + c)** time () and **O(n)** space, where the function is
+    /// **O(m)**, *n* is the length of the map, and *c* the capacity. The sort is stable.
+    pub fn sort_by_cached_key<T, F>(&mut self, mut sort_key: F)
+    where
+        T: Ord,
+        F: FnMut(&K, &V) -> T,
+    {
+        self.with_entries(move |entries| {
+            entries.sort_by_cached_key(move |a| sort_key(&a.key, &a.value));
+        });
+    }
+
+    /// Search over a sorted map for a key.
+    ///
+    /// Returns the position where that key is present, or the position where it can be inserted to
+    /// maintain the sort. See [`slice::binary_search`] for more details.
+    ///
+    /// Computes in **O(log(n))** time, which is notably less scalable than looking the key up
+    /// using [`get_index_of`][IndexMap::get_index_of], but this can also position missing keys.
+    pub fn binary_search_keys(&self, x: &K) -> Result<usize, usize>
+    where
+        K: Ord,
+    {
+        self.as_slice().binary_search_keys(x)
+    }
+
+    /// Search over a sorted map with a comparator function.
+    ///
+    /// Returns the position where that value is present, or the position where it can be inserted
+    /// to maintain the sort. See [`slice::binary_search_by`] for more details.
+    ///
+    /// Computes in **O(log(n))** time.
+    #[inline]
+    pub fn binary_search_by<'a, F>(&'a self, f: F) -> Result<usize, usize>
+    where
+        F: FnMut(&'a K, &'a V) -> Ordering,
+    {
+        self.as_slice().binary_search_by(f)
+    }
+
+    /// Search over a sorted map with an extraction function.
+    ///
+    /// Returns the position where that value is present, or the position where it can be inserted
+    /// to maintain the sort. See [`slice::binary_search_by_key`] for more details.
+    ///
+    /// Computes in **O(log(n))** time.
+    #[inline]
+    pub fn binary_search_by_key<'a, B, F>(&'a self, b: &B, f: F) -> Result<usize, usize>
+    where
+        F: FnMut(&'a K, &'a V) -> B,
+        B: Ord,
+    {
+        self.as_slice().binary_search_by_key(b, f)
+    }
+
+    /// Returns the index of the partition point of a sorted map according to the given predicate
+    /// (the index of the first element of the second partition).
+    ///
+    /// See [`slice::partition_point`] for more details.
+    ///
+    /// Computes in **O(log(n))** time.
+    #[must_use]
+    pub fn partition_point<P>(&self, pred: P) -> usize
+    where
+        P: FnMut(&K, &V) -> bool,
+    {
+        self.as_slice().partition_point(pred)
     }
 
     /// Reverses the order of the map’s key-value pairs in place.
@@ -770,9 +980,28 @@ where
     pub fn reverse(&mut self) {
         self.core.reverse()
     }
-}
 
-impl<K, V, S> IndexMap<K, V, S> {
+    /// Returns a slice of all the key-value pairs in the map.
+    ///
+    /// Computes in **O(1)** time.
+    pub fn as_slice(&self) -> &Slice<K, V> {
+        Slice::from_slice(self.as_entries())
+    }
+
+    /// Returns a mutable slice of all the key-value pairs in the map.
+    ///
+    /// Computes in **O(1)** time.
+    pub fn as_mut_slice(&mut self) -> &mut Slice<K, V> {
+        Slice::from_mut_slice(self.as_entries_mut())
+    }
+
+    /// Converts into a boxed slice of all the key-value pairs in the map.
+    ///
+    /// Note that this will drop the inner hash table and any excess capacity.
+    pub fn into_boxed_slice(self) -> Box<Slice<K, V>> {
+        Slice::from_boxed(self.into_entries().into_boxed_slice())
+    }
+
     /// Get a key-value pair by index
     ///
     /// Valid indices are *0 <= index < self.len()*
@@ -787,8 +1016,42 @@ impl<K, V, S> IndexMap<K, V, S> {
     /// Valid indices are *0 <= index < self.len()*
     ///
     /// Computes in **O(1)** time.
-    pub fn get_index_mut(&mut self, index: usize) -> Option<(&mut K, &mut V)> {
-        self.as_entries_mut().get_mut(index).map(Bucket::muts)
+    pub fn get_index_mut(&mut self, index: usize) -> Option<(&K, &mut V)> {
+        self.as_entries_mut().get_mut(index).map(Bucket::ref_mut)
+    }
+
+    /// Get an entry in the map by index for in-place manipulation.
+    ///
+    /// Valid indices are *0 <= index < self.len()*
+    ///
+    /// Computes in **O(1)** time.
+    pub fn get_index_entry(&mut self, index: usize) -> Option<IndexedEntry<'_, K, V>> {
+        if index >= self.len() {
+            return None;
+        }
+        Some(IndexedEntry::new(&mut self.core, index))
+    }
+
+    /// Returns a slice of key-value pairs in the given range of indices.
+    ///
+    /// Valid indices are *0 <= index < self.len()*
+    ///
+    /// Computes in **O(1)** time.
+    pub fn get_range<R: RangeBounds<usize>>(&self, range: R) -> Option<&Slice<K, V>> {
+        let entries = self.as_entries();
+        let range = try_simplify_range(range, entries.len())?;
+        entries.get(range).map(Slice::from_slice)
+    }
+
+    /// Returns a mutable slice of key-value pairs in the given range of indices.
+    ///
+    /// Valid indices are *0 <= index < self.len()*
+    ///
+    /// Computes in **O(1)** time.
+    pub fn get_range_mut<R: RangeBounds<usize>>(&mut self, range: R) -> Option<&mut Slice<K, V>> {
+        let entries = self.as_entries_mut();
+        let range = try_simplify_range(range, entries.len())?;
+        entries.get_mut(range).map(Slice::from_mut_slice)
     }
 
     /// Get the first key-value pair
@@ -823,7 +1086,7 @@ impl<K, V, S> IndexMap<K, V, S> {
     ///
     /// Valid indices are *0 <= index < self.len()*
     ///
-    /// Like `Vec::swap_remove`, the pair is removed by swapping it with the
+    /// Like [`Vec::swap_remove`], the pair is removed by swapping it with the
     /// last element of the map and popping it off. **This perturbs
     /// the position of what used to be the last element!**
     ///
@@ -836,7 +1099,7 @@ impl<K, V, S> IndexMap<K, V, S> {
     ///
     /// Valid indices are *0 <= index < self.len()*
     ///
-    /// Like `Vec::remove`, the pair is removed by shifting all of the
+    /// Like [`Vec::remove`], the pair is removed by shifting all of the
     /// elements that follow it, preserving their relative order.
     /// **This perturbs the index of all of those elements!**
     ///
@@ -861,386 +1124,14 @@ impl<K, V, S> IndexMap<K, V, S> {
     /// Swaps the position of two key-value pairs in the map.
     ///
     /// ***Panics*** if `a` or `b` are out of bounds.
+    ///
+    /// Computes in **O(1)** time (average).
     pub fn swap_indices(&mut self, a: usize, b: usize) {
         self.core.swap_indices(a, b)
     }
 }
 
-/// An iterator over the keys of a `IndexMap`.
-///
-/// This `struct` is created by the [`keys`] method on [`IndexMap`]. See its
-/// documentation for more.
-///
-/// [`keys`]: struct.IndexMap.html#method.keys
-/// [`IndexMap`]: struct.IndexMap.html
-pub struct Keys<'a, K, V> {
-    iter: SliceIter<'a, Bucket<K, V>>,
-}
-
-impl<'a, K, V> Iterator for Keys<'a, K, V> {
-    type Item = &'a K;
-
-    iterator_methods!(Bucket::key_ref);
-}
-
-impl<K, V> DoubleEndedIterator for Keys<'_, K, V> {
-    double_ended_iterator_methods!(Bucket::key_ref);
-}
-
-impl<K, V> ExactSizeIterator for Keys<'_, K, V> {
-    fn len(&self) -> usize {
-        self.iter.len()
-    }
-}
-
-impl<K, V> FusedIterator for Keys<'_, K, V> {}
-
-// FIXME(#26925) Remove in favor of `#[derive(Clone)]`
-impl<K, V> Clone for Keys<'_, K, V> {
-    fn clone(&self) -> Self {
-        Keys {
-            iter: self.iter.clone(),
-        }
-    }
-}
-
-impl<K: fmt::Debug, V> fmt::Debug for Keys<'_, K, V> {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        f.debug_list().entries(self.clone()).finish()
-    }
-}
-
-/// An owning iterator over the keys of a `IndexMap`.
-///
-/// This `struct` is created by the [`into_keys`] method on [`IndexMap`].
-/// See its documentation for more.
-///
-/// [`IndexMap`]: struct.IndexMap.html
-/// [`into_keys`]: struct.IndexMap.html#method.into_keys
-pub struct IntoKeys<K, V> {
-    iter: vec::IntoIter<Bucket<K, V>>,
-}
-
-impl<K, V> Iterator for IntoKeys<K, V> {
-    type Item = K;
-
-    iterator_methods!(Bucket::key);
-}
-
-impl<K, V> DoubleEndedIterator for IntoKeys<K, V> {
-    double_ended_iterator_methods!(Bucket::key);
-}
-
-impl<K, V> ExactSizeIterator for IntoKeys<K, V> {
-    fn len(&self) -> usize {
-        self.iter.len()
-    }
-}
-
-impl<K, V> FusedIterator for IntoKeys<K, V> {}
-
-impl<K: fmt::Debug, V> fmt::Debug for IntoKeys<K, V> {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        let iter = self.iter.as_slice().iter().map(Bucket::key_ref);
-        f.debug_list().entries(iter).finish()
-    }
-}
-
-/// An iterator over the values of a `IndexMap`.
-///
-/// This `struct` is created by the [`values`] method on [`IndexMap`]. See its
-/// documentation for more.
-///
-/// [`values`]: struct.IndexMap.html#method.values
-/// [`IndexMap`]: struct.IndexMap.html
-pub struct Values<'a, K, V> {
-    iter: SliceIter<'a, Bucket<K, V>>,
-}
-
-impl<'a, K, V> Iterator for Values<'a, K, V> {
-    type Item = &'a V;
-
-    iterator_methods!(Bucket::value_ref);
-}
-
-impl<K, V> DoubleEndedIterator for Values<'_, K, V> {
-    double_ended_iterator_methods!(Bucket::value_ref);
-}
-
-impl<K, V> ExactSizeIterator for Values<'_, K, V> {
-    fn len(&self) -> usize {
-        self.iter.len()
-    }
-}
-
-impl<K, V> FusedIterator for Values<'_, K, V> {}
-
-// FIXME(#26925) Remove in favor of `#[derive(Clone)]`
-impl<K, V> Clone for Values<'_, K, V> {
-    fn clone(&self) -> Self {
-        Values {
-            iter: self.iter.clone(),
-        }
-    }
-}
-
-impl<K, V: fmt::Debug> fmt::Debug for Values<'_, K, V> {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        f.debug_list().entries(self.clone()).finish()
-    }
-}
-
-/// A mutable iterator over the values of a `IndexMap`.
-///
-/// This `struct` is created by the [`values_mut`] method on [`IndexMap`]. See its
-/// documentation for more.
-///
-/// [`values_mut`]: struct.IndexMap.html#method.values_mut
-/// [`IndexMap`]: struct.IndexMap.html
-pub struct ValuesMut<'a, K, V> {
-    iter: SliceIterMut<'a, Bucket<K, V>>,
-}
-
-impl<'a, K, V> Iterator for ValuesMut<'a, K, V> {
-    type Item = &'a mut V;
-
-    iterator_methods!(Bucket::value_mut);
-}
-
-impl<K, V> DoubleEndedIterator for ValuesMut<'_, K, V> {
-    double_ended_iterator_methods!(Bucket::value_mut);
-}
-
-impl<K, V> ExactSizeIterator for ValuesMut<'_, K, V> {
-    fn len(&self) -> usize {
-        self.iter.len()
-    }
-}
-
-impl<K, V> FusedIterator for ValuesMut<'_, K, V> {}
-
-impl<K, V: fmt::Debug> fmt::Debug for ValuesMut<'_, K, V> {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        let iter = self.iter.as_slice().iter().map(Bucket::value_ref);
-        f.debug_list().entries(iter).finish()
-    }
-}
-
-/// An owning iterator over the values of a `IndexMap`.
-///
-/// This `struct` is created by the [`into_values`] method on [`IndexMap`].
-/// See its documentation for more.
-///
-/// [`IndexMap`]: struct.IndexMap.html
-/// [`into_values`]: struct.IndexMap.html#method.into_values
-pub struct IntoValues<K, V> {
-    iter: vec::IntoIter<Bucket<K, V>>,
-}
-
-impl<K, V> Iterator for IntoValues<K, V> {
-    type Item = V;
-
-    iterator_methods!(Bucket::value);
-}
-
-impl<K, V> DoubleEndedIterator for IntoValues<K, V> {
-    double_ended_iterator_methods!(Bucket::value);
-}
-
-impl<K, V> ExactSizeIterator for IntoValues<K, V> {
-    fn len(&self) -> usize {
-        self.iter.len()
-    }
-}
-
-impl<K, V> FusedIterator for IntoValues<K, V> {}
-
-impl<K, V: fmt::Debug> fmt::Debug for IntoValues<K, V> {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        let iter = self.iter.as_slice().iter().map(Bucket::value_ref);
-        f.debug_list().entries(iter).finish()
-    }
-}
-
-/// An iterator over the entries of a `IndexMap`.
-///
-/// This `struct` is created by the [`iter`] method on [`IndexMap`]. See its
-/// documentation for more.
-///
-/// [`iter`]: struct.IndexMap.html#method.iter
-/// [`IndexMap`]: struct.IndexMap.html
-pub struct Iter<'a, K, V> {
-    iter: SliceIter<'a, Bucket<K, V>>,
-}
-
-impl<'a, K, V> Iterator for Iter<'a, K, V> {
-    type Item = (&'a K, &'a V);
-
-    iterator_methods!(Bucket::refs);
-}
-
-impl<K, V> DoubleEndedIterator for Iter<'_, K, V> {
-    double_ended_iterator_methods!(Bucket::refs);
-}
-
-impl<K, V> ExactSizeIterator for Iter<'_, K, V> {
-    fn len(&self) -> usize {
-        self.iter.len()
-    }
-}
-
-impl<K, V> FusedIterator for Iter<'_, K, V> {}
-
-// FIXME(#26925) Remove in favor of `#[derive(Clone)]`
-impl<K, V> Clone for Iter<'_, K, V> {
-    fn clone(&self) -> Self {
-        Iter {
-            iter: self.iter.clone(),
-        }
-    }
-}
-
-impl<K: fmt::Debug, V: fmt::Debug> fmt::Debug for Iter<'_, K, V> {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        f.debug_list().entries(self.clone()).finish()
-    }
-}
-
-/// A mutable iterator over the entries of a `IndexMap`.
-///
-/// This `struct` is created by the [`iter_mut`] method on [`IndexMap`]. See its
-/// documentation for more.
-///
-/// [`iter_mut`]: struct.IndexMap.html#method.iter_mut
-/// [`IndexMap`]: struct.IndexMap.html
-pub struct IterMut<'a, K, V> {
-    iter: SliceIterMut<'a, Bucket<K, V>>,
-}
-
-impl<'a, K, V> Iterator for IterMut<'a, K, V> {
-    type Item = (&'a K, &'a mut V);
-
-    iterator_methods!(Bucket::ref_mut);
-}
-
-impl<K, V> DoubleEndedIterator for IterMut<'_, K, V> {
-    double_ended_iterator_methods!(Bucket::ref_mut);
-}
-
-impl<K, V> ExactSizeIterator for IterMut<'_, K, V> {
-    fn len(&self) -> usize {
-        self.iter.len()
-    }
-}
-
-impl<K, V> FusedIterator for IterMut<'_, K, V> {}
-
-impl<K: fmt::Debug, V: fmt::Debug> fmt::Debug for IterMut<'_, K, V> {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        let iter = self.iter.as_slice().iter().map(Bucket::refs);
-        f.debug_list().entries(iter).finish()
-    }
-}
-
-/// An owning iterator over the entries of a `IndexMap`.
-///
-/// This `struct` is created by the [`into_iter`] method on [`IndexMap`]
-/// (provided by the `IntoIterator` trait). See its documentation for more.
-///
-/// [`into_iter`]: struct.IndexMap.html#method.into_iter
-/// [`IndexMap`]: struct.IndexMap.html
-pub struct IntoIter<K, V> {
-    iter: vec::IntoIter<Bucket<K, V>>,
-}
-
-impl<K, V> Iterator for IntoIter<K, V> {
-    type Item = (K, V);
-
-    iterator_methods!(Bucket::key_value);
-}
-
-impl<K, V> DoubleEndedIterator for IntoIter<K, V> {
-    double_ended_iterator_methods!(Bucket::key_value);
-}
-
-impl<K, V> ExactSizeIterator for IntoIter<K, V> {
-    fn len(&self) -> usize {
-        self.iter.len()
-    }
-}
-
-impl<K, V> FusedIterator for IntoIter<K, V> {}
-
-impl<K: fmt::Debug, V: fmt::Debug> fmt::Debug for IntoIter<K, V> {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        let iter = self.iter.as_slice().iter().map(Bucket::refs);
-        f.debug_list().entries(iter).finish()
-    }
-}
-
-/// A draining iterator over the entries of a `IndexMap`.
-///
-/// This `struct` is created by the [`drain`] method on [`IndexMap`]. See its
-/// documentation for more.
-///
-/// [`drain`]: struct.IndexMap.html#method.drain
-/// [`IndexMap`]: struct.IndexMap.html
-pub struct Drain<'a, K, V> {
-    pub(crate) iter: vec::Drain<'a, Bucket<K, V>>,
-}
-
-impl<K, V> Iterator for Drain<'_, K, V> {
-    type Item = (K, V);
-
-    iterator_methods!(Bucket::key_value);
-}
-
-impl<K, V> DoubleEndedIterator for Drain<'_, K, V> {
-    double_ended_iterator_methods!(Bucket::key_value);
-}
-
-impl<K, V> ExactSizeIterator for Drain<'_, K, V> {
-    fn len(&self) -> usize {
-        self.iter.len()
-    }
-}
-
-impl<K, V> FusedIterator for Drain<'_, K, V> {}
-
-impl<K: fmt::Debug, V: fmt::Debug> fmt::Debug for Drain<'_, K, V> {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        let iter = self.iter.as_slice().iter().map(Bucket::refs);
-        f.debug_list().entries(iter).finish()
-    }
-}
-
-impl<'a, K, V, S> IntoIterator for &'a IndexMap<K, V, S> {
-    type Item = (&'a K, &'a V);
-    type IntoIter = Iter<'a, K, V>;
-    fn into_iter(self) -> Self::IntoIter {
-        self.iter()
-    }
-}
-
-impl<'a, K, V, S> IntoIterator for &'a mut IndexMap<K, V, S> {
-    type Item = (&'a K, &'a mut V);
-    type IntoIter = IterMut<'a, K, V>;
-    fn into_iter(self) -> Self::IntoIter {
-        self.iter_mut()
-    }
-}
-
-impl<K, V, S> IntoIterator for IndexMap<K, V, S> {
-    type Item = (K, V);
-    type IntoIter = IntoIter<K, V>;
-    fn into_iter(self) -> Self::IntoIter {
-        IntoIter {
-            iter: self.into_entries().into_iter(),
-        }
-    }
-}
-
-/// Access `IndexMap` values corresponding to a key.
+/// Access [`IndexMap`] values corresponding to a key.
 ///
 /// # Examples
 ///
@@ -1265,7 +1156,6 @@ impl<K, V, S> IntoIterator for IndexMap<K, V, S> {
 impl<K, V, Q: ?Sized, S> Index<&Q> for IndexMap<K, V, S>
 where
     Q: Hash + Equivalent<K>,
-    K: Hash + Eq,
     S: BuildHasher,
 {
     type Output = V;
@@ -1278,7 +1168,7 @@ where
     }
 }
 
-/// Access `IndexMap` values corresponding to a key.
+/// Access [`IndexMap`] values corresponding to a key.
 ///
 /// Mutable indexing allows changing / updating values of key-value
 /// pairs that are already present.
@@ -1310,7 +1200,6 @@ where
 impl<K, V, Q: ?Sized, S> IndexMut<&Q> for IndexMap<K, V, S>
 where
     Q: Hash + Equivalent<K>,
-    K: Hash + Eq,
     S: BuildHasher,
 {
     /// Returns a mutable reference to the value corresponding to the supplied `key`.
@@ -1321,7 +1210,11 @@ where
     }
 }
 
-/// Access `IndexMap` values at indexed positions.
+/// Access [`IndexMap`] values at indexed positions.
+///
+/// See [`Index<usize> for Keys`][keys] to access a map's keys instead.
+///
+/// [keys]: Keys#impl-Index<usize>-for-Keys<'a,+K,+V>
 ///
 /// # Examples
 ///
@@ -1362,12 +1255,12 @@ impl<K, V, S> Index<usize> for IndexMap<K, V, S> {
     }
 }
 
-/// Access `IndexMap` values at indexed positions.
+/// Access [`IndexMap`] values at indexed positions.
 ///
 /// Mutable indexing allows changing / updating indexed values
 /// that are already present.
 ///
-/// You can **not** insert new values with index syntax, use `.insert()`.
+/// You can **not** insert new values with index syntax -- use [`.insert()`][IndexMap::insert].
 ///
 /// # Examples
 ///
@@ -1411,7 +1304,7 @@ where
     /// iterable.
     ///
     /// `from_iter` uses the same logic as `extend`. See
-    /// [`extend`](#method.extend) for more details.
+    /// [`extend`][IndexMap::extend] for more details.
     fn from_iter<I: IntoIterator<Item = (K, V)>>(iterable: I) -> Self {
         let iter = iterable.into_iter();
         let (low, _) = iter.size_hint();
@@ -1421,7 +1314,8 @@ where
     }
 }
 
-#[cfg(has_std)]
+#[cfg(feature = "std")]
+#[cfg_attr(docsrs, doc(cfg(feature = "std")))]
 impl<K, V, const N: usize> From<[(K, V); N]> for IndexMap<K, V, RandomState>
 where
     K: Hash + Eq,
@@ -1447,7 +1341,7 @@ where
 {
     /// Extend the map with all key-value pairs in the iterable.
     ///
-    /// This is equivalent to calling [`insert`](#method.insert) for each of
+    /// This is equivalent to calling [`insert`][IndexMap::insert] for each of
     /// them in order, which means that for keys that already existed
     /// in the map, their value is updated but it keeps the existing order.
     ///
@@ -1491,7 +1385,7 @@ impl<K, V, S> Default for IndexMap<K, V, S>
 where
     S: Default,
 {
-    /// Return an empty `IndexMap`
+    /// Return an empty [`IndexMap`]
     fn default() -> Self {
         Self::with_capacity_and_hasher(0, S::default())
     }
@@ -1521,427 +1415,3 @@ where
     S: BuildHasher,
 {
 }
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-    use std::string::String;
-
-    #[test]
-    fn it_works() {
-        let mut map = IndexMap::new();
-        assert_eq!(map.is_empty(), true);
-        map.insert(1, ());
-        map.insert(1, ());
-        assert_eq!(map.len(), 1);
-        assert!(map.get(&1).is_some());
-        assert_eq!(map.is_empty(), false);
-    }
-
-    #[test]
-    fn new() {
-        let map = IndexMap::<String, String>::new();
-        println!("{:?}", map);
-        assert_eq!(map.capacity(), 0);
-        assert_eq!(map.len(), 0);
-        assert_eq!(map.is_empty(), true);
-    }
-
-    #[test]
-    fn insert() {
-        let insert = [0, 4, 2, 12, 8, 7, 11, 5];
-        let not_present = [1, 3, 6, 9, 10];
-        let mut map = IndexMap::with_capacity(insert.len());
-
-        for (i, &elt) in insert.iter().enumerate() {
-            assert_eq!(map.len(), i);
-            map.insert(elt, elt);
-            assert_eq!(map.len(), i + 1);
-            assert_eq!(map.get(&elt), Some(&elt));
-            assert_eq!(map[&elt], elt);
-        }
-        println!("{:?}", map);
-
-        for &elt in &not_present {
-            assert!(map.get(&elt).is_none());
-        }
-    }
-
-    #[test]
-    fn insert_full() {
-        let insert = vec![9, 2, 7, 1, 4, 6, 13];
-        let present = vec![1, 6, 2];
-        let mut map = IndexMap::with_capacity(insert.len());
-
-        for (i, &elt) in insert.iter().enumerate() {
-            assert_eq!(map.len(), i);
-            let (index, existing) = map.insert_full(elt, elt);
-            assert_eq!(existing, None);
-            assert_eq!(Some(index), map.get_full(&elt).map(|x| x.0));
-            assert_eq!(map.len(), i + 1);
-        }
-
-        let len = map.len();
-        for &elt in &present {
-            let (index, existing) = map.insert_full(elt, elt);
-            assert_eq!(existing, Some(elt));
-            assert_eq!(Some(index), map.get_full(&elt).map(|x| x.0));
-            assert_eq!(map.len(), len);
-        }
-    }
-
-    #[test]
-    fn insert_2() {
-        let mut map = IndexMap::with_capacity(16);
-
-        let mut keys = vec![];
-        keys.extend(0..16);
-        keys.extend(if cfg!(miri) { 32..64 } else { 128..267 });
-
-        for &i in &keys {
-            let old_map = map.clone();
-            map.insert(i, ());
-            for key in old_map.keys() {
-                if map.get(key).is_none() {
-                    println!("old_map: {:?}", old_map);
-                    println!("map: {:?}", map);
-                    panic!("did not find {} in map", key);
-                }
-            }
-        }
-
-        for &i in &keys {
-            assert!(map.get(&i).is_some(), "did not find {}", i);
-        }
-    }
-
-    #[test]
-    fn insert_order() {
-        let insert = [0, 4, 2, 12, 8, 7, 11, 5, 3, 17, 19, 22, 23];
-        let mut map = IndexMap::new();
-
-        for &elt in &insert {
-            map.insert(elt, ());
-        }
-
-        assert_eq!(map.keys().count(), map.len());
-        assert_eq!(map.keys().count(), insert.len());
-        for (a, b) in insert.iter().zip(map.keys()) {
-            assert_eq!(a, b);
-        }
-        for (i, k) in (0..insert.len()).zip(map.keys()) {
-            assert_eq!(map.get_index(i).unwrap().0, k);
-        }
-    }
-
-    #[test]
-    fn grow() {
-        let insert = [0, 4, 2, 12, 8, 7, 11];
-        let not_present = [1, 3, 6, 9, 10];
-        let mut map = IndexMap::with_capacity(insert.len());
-
-        for (i, &elt) in insert.iter().enumerate() {
-            assert_eq!(map.len(), i);
-            map.insert(elt, elt);
-            assert_eq!(map.len(), i + 1);
-            assert_eq!(map.get(&elt), Some(&elt));
-            assert_eq!(map[&elt], elt);
-        }
-
-        println!("{:?}", map);
-        for &elt in &insert {
-            map.insert(elt * 10, elt);
-        }
-        for &elt in &insert {
-            map.insert(elt * 100, elt);
-        }
-        for (i, &elt) in insert.iter().cycle().enumerate().take(100) {
-            map.insert(elt * 100 + i as i32, elt);
-        }
-        println!("{:?}", map);
-        for &elt in &not_present {
-            assert!(map.get(&elt).is_none());
-        }
-    }
-
-    #[test]
-    fn reserve() {
-        let mut map = IndexMap::<usize, usize>::new();
-        assert_eq!(map.capacity(), 0);
-        map.reserve(100);
-        let capacity = map.capacity();
-        assert!(capacity >= 100);
-        for i in 0..capacity {
-            assert_eq!(map.len(), i);
-            map.insert(i, i * i);
-            assert_eq!(map.len(), i + 1);
-            assert_eq!(map.capacity(), capacity);
-            assert_eq!(map.get(&i), Some(&(i * i)));
-        }
-        map.insert(capacity, std::usize::MAX);
-        assert_eq!(map.len(), capacity + 1);
-        assert!(map.capacity() > capacity);
-        assert_eq!(map.get(&capacity), Some(&std::usize::MAX));
-    }
-
-    #[test]
-    fn shrink_to_fit() {
-        let mut map = IndexMap::<usize, usize>::new();
-        assert_eq!(map.capacity(), 0);
-        for i in 0..100 {
-            assert_eq!(map.len(), i);
-            map.insert(i, i * i);
-            assert_eq!(map.len(), i + 1);
-            assert!(map.capacity() >= i + 1);
-            assert_eq!(map.get(&i), Some(&(i * i)));
-            map.shrink_to_fit();
-            assert_eq!(map.len(), i + 1);
-            assert_eq!(map.capacity(), i + 1);
-            assert_eq!(map.get(&i), Some(&(i * i)));
-        }
-    }
-
-    #[test]
-    fn remove() {
-        let insert = [0, 4, 2, 12, 8, 7, 11, 5, 3, 17, 19, 22, 23];
-        let mut map = IndexMap::new();
-
-        for &elt in &insert {
-            map.insert(elt, elt);
-        }
-
-        assert_eq!(map.keys().count(), map.len());
-        assert_eq!(map.keys().count(), insert.len());
-        for (a, b) in insert.iter().zip(map.keys()) {
-            assert_eq!(a, b);
-        }
-
-        let remove_fail = [99, 77];
-        let remove = [4, 12, 8, 7];
-
-        for &key in &remove_fail {
-            assert!(map.swap_remove_full(&key).is_none());
-        }
-        println!("{:?}", map);
-        for &key in &remove {
-            //println!("{:?}", map);
-            let index = map.get_full(&key).unwrap().0;
-            assert_eq!(map.swap_remove_full(&key), Some((index, key, key)));
-        }
-        println!("{:?}", map);
-
-        for key in &insert {
-            assert_eq!(map.get(key).is_some(), !remove.contains(key));
-        }
-        assert_eq!(map.len(), insert.len() - remove.len());
-        assert_eq!(map.keys().count(), insert.len() - remove.len());
-    }
-
-    #[test]
-    fn remove_to_empty() {
-        let mut map = indexmap! { 0 => 0, 4 => 4, 5 => 5 };
-        map.swap_remove(&5).unwrap();
-        map.swap_remove(&4).unwrap();
-        map.swap_remove(&0).unwrap();
-        assert!(map.is_empty());
-    }
-
-    #[test]
-    fn swap_remove_index() {
-        let insert = [0, 4, 2, 12, 8, 7, 11, 5, 3, 17, 19, 22, 23];
-        let mut map = IndexMap::new();
-
-        for &elt in &insert {
-            map.insert(elt, elt * 2);
-        }
-
-        let mut vector = insert.to_vec();
-        let remove_sequence = &[3, 3, 10, 4, 5, 4, 3, 0, 1];
-
-        // check that the same swap remove sequence on vec and map
-        // have the same result.
-        for &rm in remove_sequence {
-            let out_vec = vector.swap_remove(rm);
-            let (out_map, _) = map.swap_remove_index(rm).unwrap();
-            assert_eq!(out_vec, out_map);
-        }
-        assert_eq!(vector.len(), map.len());
-        for (a, b) in vector.iter().zip(map.keys()) {
-            assert_eq!(a, b);
-        }
-    }
-
-    #[test]
-    fn partial_eq_and_eq() {
-        let mut map_a = IndexMap::new();
-        map_a.insert(1, "1");
-        map_a.insert(2, "2");
-        let mut map_b = map_a.clone();
-        assert_eq!(map_a, map_b);
-        map_b.swap_remove(&1);
-        assert_ne!(map_a, map_b);
-
-        let map_c: IndexMap<_, String> = map_b.into_iter().map(|(k, v)| (k, v.into())).collect();
-        assert_ne!(map_a, map_c);
-        assert_ne!(map_c, map_a);
-    }
-
-    #[test]
-    fn extend() {
-        let mut map = IndexMap::new();
-        map.extend(vec![(&1, &2), (&3, &4)]);
-        map.extend(vec![(5, 6)]);
-        assert_eq!(
-            map.into_iter().collect::<Vec<_>>(),
-            vec![(1, 2), (3, 4), (5, 6)]
-        );
-    }
-
-    #[test]
-    fn entry() {
-        let mut map = IndexMap::new();
-
-        map.insert(1, "1");
-        map.insert(2, "2");
-        {
-            let e = map.entry(3);
-            assert_eq!(e.index(), 2);
-            let e = e.or_insert("3");
-            assert_eq!(e, &"3");
-        }
-
-        let e = map.entry(2);
-        assert_eq!(e.index(), 1);
-        assert_eq!(e.key(), &2);
-        match e {
-            Entry::Occupied(ref e) => assert_eq!(e.get(), &"2"),
-            Entry::Vacant(_) => panic!(),
-        }
-        assert_eq!(e.or_insert("4"), &"2");
-    }
-
-    #[test]
-    fn entry_and_modify() {
-        let mut map = IndexMap::new();
-
-        map.insert(1, "1");
-        map.entry(1).and_modify(|x| *x = "2");
-        assert_eq!(Some(&"2"), map.get(&1));
-
-        map.entry(2).and_modify(|x| *x = "doesn't exist");
-        assert_eq!(None, map.get(&2));
-    }
-
-    #[test]
-    fn entry_or_default() {
-        let mut map = IndexMap::new();
-
-        #[derive(Debug, PartialEq)]
-        enum TestEnum {
-            DefaultValue,
-            NonDefaultValue,
-        }
-
-        impl Default for TestEnum {
-            fn default() -> Self {
-                TestEnum::DefaultValue
-            }
-        }
-
-        map.insert(1, TestEnum::NonDefaultValue);
-        assert_eq!(&mut TestEnum::NonDefaultValue, map.entry(1).or_default());
-
-        assert_eq!(&mut TestEnum::DefaultValue, map.entry(2).or_default());
-    }
-
-    #[test]
-    fn occupied_entry_key() {
-        // These keys match hash and equality, but their addresses are distinct.
-        let (k1, k2) = (&mut 1, &mut 1);
-        let k1_ptr = k1 as *const i32;
-        let k2_ptr = k2 as *const i32;
-        assert_ne!(k1_ptr, k2_ptr);
-
-        let mut map = IndexMap::new();
-        map.insert(k1, "value");
-        match map.entry(k2) {
-            Entry::Occupied(ref e) => {
-                // `OccupiedEntry::key` should reference the key in the map,
-                // not the key that was used to find the entry.
-                let ptr = *e.key() as *const i32;
-                assert_eq!(ptr, k1_ptr);
-                assert_ne!(ptr, k2_ptr);
-            }
-            Entry::Vacant(_) => panic!(),
-        }
-    }
-
-    #[test]
-    fn keys() {
-        let vec = vec![(1, 'a'), (2, 'b'), (3, 'c')];
-        let map: IndexMap<_, _> = vec.into_iter().collect();
-        let keys: Vec<_> = map.keys().copied().collect();
-        assert_eq!(keys.len(), 3);
-        assert!(keys.contains(&1));
-        assert!(keys.contains(&2));
-        assert!(keys.contains(&3));
-    }
-
-    #[test]
-    fn into_keys() {
-        let vec = vec![(1, 'a'), (2, 'b'), (3, 'c')];
-        let map: IndexMap<_, _> = vec.into_iter().collect();
-        let keys: Vec<i32> = map.into_keys().collect();
-        assert_eq!(keys.len(), 3);
-        assert!(keys.contains(&1));
-        assert!(keys.contains(&2));
-        assert!(keys.contains(&3));
-    }
-
-    #[test]
-    fn values() {
-        let vec = vec![(1, 'a'), (2, 'b'), (3, 'c')];
-        let map: IndexMap<_, _> = vec.into_iter().collect();
-        let values: Vec<_> = map.values().copied().collect();
-        assert_eq!(values.len(), 3);
-        assert!(values.contains(&'a'));
-        assert!(values.contains(&'b'));
-        assert!(values.contains(&'c'));
-    }
-
-    #[test]
-    fn values_mut() {
-        let vec = vec![(1, 1), (2, 2), (3, 3)];
-        let mut map: IndexMap<_, _> = vec.into_iter().collect();
-        for value in map.values_mut() {
-            *value *= 2
-        }
-        let values: Vec<_> = map.values().copied().collect();
-        assert_eq!(values.len(), 3);
-        assert!(values.contains(&2));
-        assert!(values.contains(&4));
-        assert!(values.contains(&6));
-    }
-
-    #[test]
-    fn into_values() {
-        let vec = vec![(1, 'a'), (2, 'b'), (3, 'c')];
-        let map: IndexMap<_, _> = vec.into_iter().collect();
-        let values: Vec<char> = map.into_values().collect();
-        assert_eq!(values.len(), 3);
-        assert!(values.contains(&'a'));
-        assert!(values.contains(&'b'));
-        assert!(values.contains(&'c'));
-    }
-
-    #[test]
-    #[cfg(has_std)]
-    fn from_array() {
-        let map = IndexMap::from([(1, 2), (3, 4)]);
-        let mut expected = IndexMap::new();
-        expected.insert(1, 2);
-        expected.insert(3, 4);
-
-        assert_eq!(map, expected)
-    }
-}
diff --git a/third_party/rust/indexmap/src/map/core.rs b/third_party/rust/indexmap/src/map/core.rs
index ea7aaae62e..16e87c7c6a 100644
--- a/third_party/rust/indexmap/src/map/core.rs
+++ b/third_party/rust/indexmap/src/map/core.rs
@@ -7,19 +7,22 @@
 //!
 //! However, we should probably not let this show in the public API or docs.
 
+mod entry;
 mod raw;
 
+pub mod raw_entry_v1;
+
 use hashbrown::raw::RawTable;
 
-use crate::vec::{Drain, Vec};
-use core::cmp;
-use core::fmt;
-use core::mem::replace;
+use crate::vec::{self, Vec};
+use crate::TryReserveError;
+use core::mem;
 use core::ops::RangeBounds;
 
-use crate::equivalent::Equivalent;
 use crate::util::simplify_range;
-use crate::{Bucket, Entries, HashValue};
+use crate::{Bucket, Entries, Equivalent, HashValue};
+
+pub use entry::{Entry, IndexedEntry, OccupiedEntry, VacantEntry};
 
 /// Core of the map that does not depend on S
 pub(crate) struct IndexMapCore<K, V> {
@@ -62,29 +65,30 @@ where
     V: Clone,
 {
     fn clone(&self) -> Self {
-        let indices = self.indices.clone();
-        let mut entries = Vec::with_capacity(indices.capacity());
-        entries.clone_from(&self.entries);
-        IndexMapCore { indices, entries }
+        let mut new = Self::new();
+        new.clone_from(self);
+        new
     }
 
     fn clone_from(&mut self, other: &Self) {
         let hasher = get_hash(&other.entries);
         self.indices.clone_from_with_hasher(&other.indices, hasher);
         if self.entries.capacity() < other.entries.len() {
-            // If we must resize, match the indices capacity
-            self.reserve_entries();
+            // If we must resize, match the indices capacity.
+            let additional = other.entries.len() - self.entries.len();
+            self.reserve_entries(additional);
         }
         self.entries.clone_from(&other.entries);
     }
 }
 
-impl<K, V> fmt::Debug for IndexMapCore<K, V>
+#[cfg(feature = "test_debug")]
+impl<K, V> core::fmt::Debug for IndexMapCore<K, V>
 where
-    K: fmt::Debug,
-    V: fmt::Debug,
+    K: core::fmt::Debug,
+    V: core::fmt::Debug,
 {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
         f.debug_struct("IndexMapCore")
             .field("indices", &raw::DebugIndices(&self.indices))
             .field("entries", &self.entries)
@@ -120,6 +124,9 @@ impl<K, V> Entries for IndexMapCore<K, V> {
 }
 
 impl<K, V> IndexMapCore<K, V> {
+    /// The maximum capacity before the `entries` allocation would exceed `isize::MAX`.
+    const MAX_ENTRIES_CAPACITY: usize = (isize::MAX as usize) / mem::size_of::<Bucket<K, V>>();
+
     #[inline]
     pub(crate) const fn new() -> Self {
         IndexMapCore {
@@ -143,7 +150,7 @@ impl<K, V> IndexMapCore<K, V> {
 
     #[inline]
     pub(crate) fn capacity(&self) -> usize {
-        cmp::min(self.indices.capacity(), self.entries.capacity())
+        Ord::min(self.indices.capacity(), self.entries.capacity())
     }
 
     pub(crate) fn clear(&mut self) {
@@ -158,7 +165,7 @@ impl<K, V> IndexMapCore<K, V> {
         }
     }
 
-    pub(crate) fn drain<R>(&mut self, range: R) -> Drain<'_, Bucket<K, V>>
+    pub(crate) fn drain<R>(&mut self, range: R) -> vec::Drain<'_, Bucket<K, V>>
     where
         R: RangeBounds<usize>,
     {
@@ -190,18 +197,92 @@ impl<K, V> IndexMapCore<K, V> {
         Self { indices, entries }
     }
 
+    pub(crate) fn split_splice<R>(&mut self, range: R) -> (Self, vec::IntoIter<Bucket<K, V>>)
+    where
+        R: RangeBounds<usize>,
+    {
+        let range = simplify_range(range, self.len());
+        self.erase_indices(range.start, self.entries.len());
+        let entries = self.entries.split_off(range.end);
+        let drained = self.entries.split_off(range.start);
+
+        let mut indices = RawTable::with_capacity(entries.len());
+        raw::insert_bulk_no_grow(&mut indices, &entries);
+        (Self { indices, entries }, drained.into_iter())
+    }
+
+    /// Append from another map without checking whether items already exist.
+    pub(crate) fn append_unchecked(&mut self, other: &mut Self) {
+        self.reserve(other.len());
+        raw::insert_bulk_no_grow(&mut self.indices, &other.entries);
+        self.entries.append(&mut other.entries);
+        other.indices.clear();
+    }
+
     /// Reserve capacity for `additional` more key-value pairs.
     pub(crate) fn reserve(&mut self, additional: usize) {
         self.indices.reserve(additional, get_hash(&self.entries));
-        self.reserve_entries();
+        // Only grow entries if necessary, since we also round up capacity.
+        if additional > self.entries.capacity() - self.entries.len() {
+            self.reserve_entries(additional);
+        }
+    }
+
+    /// Reserve entries capacity, rounded up to match the indices
+    fn reserve_entries(&mut self, additional: usize) {
+        // Use a soft-limit on the maximum capacity, but if the caller explicitly
+        // requested more, do it and let them have the resulting panic.
+        let new_capacity = Ord::min(self.indices.capacity(), Self::MAX_ENTRIES_CAPACITY);
+        let try_add = new_capacity - self.entries.len();
+        if try_add > additional && self.entries.try_reserve_exact(try_add).is_ok() {
+            return;
+        }
+        self.entries.reserve_exact(additional);
     }
 
-    /// Reserve entries capacity to match the indices
-    fn reserve_entries(&mut self) {
-        let additional = self.indices.capacity() - self.entries.len();
+    /// Reserve capacity for `additional` more key-value pairs, without over-allocating.
+    pub(crate) fn reserve_exact(&mut self, additional: usize) {
+        self.indices.reserve(additional, get_hash(&self.entries));
         self.entries.reserve_exact(additional);
     }
 
+    /// Try to reserve capacity for `additional` more key-value pairs.
+    pub(crate) fn try_reserve(&mut self, additional: usize) -> Result<(), TryReserveError> {
+        self.indices
+            .try_reserve(additional, get_hash(&self.entries))
+            .map_err(TryReserveError::from_hashbrown)?;
+        // Only grow entries if necessary, since we also round up capacity.
+        if additional > self.entries.capacity() - self.entries.len() {
+            self.try_reserve_entries(additional)
+        } else {
+            Ok(())
+        }
+    }
+
+    /// Try to reserve entries capacity, rounded up to match the indices
+    fn try_reserve_entries(&mut self, additional: usize) -> Result<(), TryReserveError> {
+        // Use a soft-limit on the maximum capacity, but if the caller explicitly
+        // requested more, do it and let them have the resulting error.
+        let new_capacity = Ord::min(self.indices.capacity(), Self::MAX_ENTRIES_CAPACITY);
+        let try_add = new_capacity - self.entries.len();
+        if try_add > additional && self.entries.try_reserve_exact(try_add).is_ok() {
+            return Ok(());
+        }
+        self.entries
+            .try_reserve_exact(additional)
+            .map_err(TryReserveError::from_alloc)
+    }
+
+    /// Try to reserve capacity for `additional` more key-value pairs, without over-allocating.
+    pub(crate) fn try_reserve_exact(&mut self, additional: usize) -> Result<(), TryReserveError> {
+        self.indices
+            .try_reserve(additional, get_hash(&self.entries))
+            .map_err(TryReserveError::from_hashbrown)?;
+        self.entries
+            .try_reserve_exact(additional)
+            .map_err(TryReserveError::from_alloc)
+    }
+
     /// Shrink the capacity of the map with a lower bound
     pub(crate) fn shrink_to(&mut self, min_capacity: usize) {
         self.indices
@@ -220,18 +301,25 @@ impl<K, V> IndexMapCore<K, V> {
         }
     }
 
-    /// Append a key-value pair, *without* checking whether it already exists,
-    /// and return the pair's new index.
-    fn push(&mut self, hash: HashValue, key: K, value: V) -> usize {
-        let i = self.entries.len();
-        self.indices.insert(hash.get(), i, get_hash(&self.entries));
-        if i == self.entries.capacity() {
+    /// Append a key-value pair to `entries`, *without* checking whether it already exists.
+    fn push_entry(&mut self, hash: HashValue, key: K, value: V) {
+        if self.entries.len() == self.entries.capacity() {
             // Reserve our own capacity synced to the indices,
             // rather than letting `Vec::push` just double it.
-            self.reserve_entries();
+            self.reserve_entries(1);
         }
         self.entries.push(Bucket { hash, key, value });
-        i
+    }
+
+    /// Insert a key-value pair in `entries` at a particular index,
+    /// *without* checking whether it already exists.
+    fn insert_entry(&mut self, index: usize, hash: HashValue, key: K, value: V) {
+        if self.entries.len() == self.entries.capacity() {
+            // Reserve our own capacity synced to the indices,
+            // rather than letting `Vec::insert` just double it.
+            self.reserve_entries(1);
+        }
+        self.entries.insert(index, Bucket { hash, key, value });
     }
 
     /// Return the index in `entries` where an equivalent key can be found
@@ -247,12 +335,66 @@ impl<K, V> IndexMapCore<K, V> {
     where
         K: Eq,
     {
-        match self.get_index_of(hash, &key) {
-            Some(i) => (i, Some(replace(&mut self.entries[i].value, value))),
-            None => (self.push(hash, key, value), None),
+        match self.find_or_insert(hash, &key) {
+            Ok(i) => (i, Some(mem::replace(&mut self.entries[i].value, value))),
+            Err(i) => {
+                debug_assert_eq!(i, self.entries.len());
+                self.push_entry(hash, key, value);
+                (i, None)
+            }
+        }
+    }
+
+    /// Same as `insert_full`, except it also replaces the key
+    pub(crate) fn replace_full(
+        &mut self,
+        hash: HashValue,
+        key: K,
+        value: V,
+    ) -> (usize, Option<(K, V)>)
+    where
+        K: Eq,
+    {
+        match self.find_or_insert(hash, &key) {
+            Ok(i) => {
+                let entry = &mut self.entries[i];
+                let kv = (
+                    mem::replace(&mut entry.key, key),
+                    mem::replace(&mut entry.value, value),
+                );
+                (i, Some(kv))
+            }
+            Err(i) => {
+                debug_assert_eq!(i, self.entries.len());
+                self.push_entry(hash, key, value);
+                (i, None)
+            }
         }
     }
 
+    fn insert_unique(&mut self, hash: HashValue, key: K, value: V) -> usize {
+        let i = self.indices.len();
+        self.indices.insert(hash.get(), i, get_hash(&self.entries));
+        debug_assert_eq!(i, self.entries.len());
+        self.push_entry(hash, key, value);
+        i
+    }
+
+    fn shift_insert_unique(&mut self, index: usize, hash: HashValue, key: K, value: V) {
+        let end = self.indices.len();
+        assert!(index <= end);
+        // Increment others first so we don't have duplicate indices.
+        self.increment_indices(index, end);
+        let entries = &*self.entries;
+        self.indices.insert(hash.get(), index, move |&i| {
+            // Adjust for the incremented indices to find hashes.
+            debug_assert_ne!(i, index);
+            let i = if i < index { i } else { i - 1 };
+            entries[i].hash.get()
+        });
+        self.insert_entry(index, hash, key, value);
+    }
+
     /// Remove an entry by shifting all entries that follow it
     pub(crate) fn shift_remove_full<Q>(&mut self, hash: HashValue, key: &Q) -> Option<(usize, K, V)>
     where
@@ -339,7 +481,7 @@ impl<K, V> IndexMapCore<K, V> {
     pub(super) fn move_index(&mut self, from: usize, to: usize) {
         let from_hash = self.entries[from].hash;
         if from != to {
-            // Use a sentinal index so other indices don't collide.
+            // Use a sentinel index so other indices don't collide.
             update_index(&mut self.indices, from_hash, from, usize::MAX);
 
             // Update all other indices and rotate the entry positions.
@@ -351,11 +493,31 @@ impl<K, V> IndexMapCore<K, V> {
                 self.entries[to..=from].rotate_right(1);
             }
 
-            // Change the sentinal index to its final position.
+            // Change the sentinel index to its final position.
             update_index(&mut self.indices, from_hash, usize::MAX, to);
         }
     }
 
+    pub(crate) fn swap_indices(&mut self, a: usize, b: usize) {
+        // If they're equal and in-bounds, there's nothing to do.
+        if a == b && a < self.entries.len() {
+            return;
+        }
+
+        // We'll get a "nice" bounds-check from indexing `self.entries`,
+        // and then we expect to find it in the table as well.
+        let [ref_a, ref_b] = self
+            .indices
+            .get_many_mut(
+                [self.entries[a].hash.get(), self.entries[b].hash.get()],
+                move |i, &x| if i == 0 { x == a } else { x == b },
+            )
+            .expect("indices not found");
+
+        mem::swap(ref_a, ref_b);
+        self.entries.swap(a, b);
+    }
+
     /// Remove an entry by swapping it with the last
     pub(crate) fn swap_remove_full<Q>(&mut self, hash: HashValue, key: &Q) -> Option<(usize, K, V)>
     where
@@ -447,25 +609,9 @@ impl<K, V> IndexMapCore<K, V> {
     where
         F: FnMut(&mut K, &mut V) -> bool,
     {
-        // FIXME: This could use Vec::retain_mut with MSRV 1.61.
-        // Like Vec::retain in self.entries, but with mutable K and V.
-        // We swap-shift all the items we want to keep, truncate the rest,
-        // then rebuild the raw hash table with the new indexes.
-        let len = self.entries.len();
-        let mut n_deleted = 0;
-        for i in 0..len {
-            let will_keep = {
-                let entry = &mut self.entries[i];
-                keep(&mut entry.key, &mut entry.value)
-            };
-            if !will_keep {
-                n_deleted += 1;
-            } else if n_deleted > 0 {
-                self.entries.swap(i - n_deleted, i);
-            }
-        }
-        if n_deleted > 0 {
-            self.entries.truncate(len - n_deleted);
+        self.entries
+            .retain_mut(|entry| keep(&mut entry.key, &mut entry.value));
+        if self.entries.len() < self.indices.len() {
             self.rebuild_hash_table();
         }
     }
@@ -487,214 +633,10 @@ impl<K, V> IndexMapCore<K, V> {
     }
 }
 
-/// Entry for an existing key-value pair or a vacant location to
-/// insert one.
-pub enum Entry<'a, K, V> {
-    /// Existing slot with equivalent key.
-    Occupied(OccupiedEntry<'a, K, V>),
-    /// Vacant slot (no equivalent key in the map).
-    Vacant(VacantEntry<'a, K, V>),
-}
-
-impl<'a, K, V> Entry<'a, K, V> {
-    /// Inserts the given default value in the entry if it is vacant and returns a mutable
-    /// reference to it. Otherwise a mutable reference to an already existent value is returned.
-    ///
-    /// Computes in **O(1)** time (amortized average).
-    pub fn or_insert(self, default: V) -> &'a mut V {
-        match self {
-            Entry::Occupied(entry) => entry.into_mut(),
-            Entry::Vacant(entry) => entry.insert(default),
-        }
-    }
-
-    /// Inserts the result of the `call` function in the entry if it is vacant and returns a mutable
-    /// reference to it. Otherwise a mutable reference to an already existent value is returned.
-    ///
-    /// Computes in **O(1)** time (amortized average).
-    pub fn or_insert_with<F>(self, call: F) -> &'a mut V
-    where
-        F: FnOnce() -> V,
-    {
-        match self {
-            Entry::Occupied(entry) => entry.into_mut(),
-            Entry::Vacant(entry) => entry.insert(call()),
-        }
-    }
-
-    /// Inserts the result of the `call` function with a reference to the entry's key if it is
-    /// vacant, and returns a mutable reference to the new value. Otherwise a mutable reference to
-    /// an already existent value is returned.
-    ///
-    /// Computes in **O(1)** time (amortized average).
-    pub fn or_insert_with_key<F>(self, call: F) -> &'a mut V
-    where
-        F: FnOnce(&K) -> V,
-    {
-        match self {
-            Entry::Occupied(entry) => entry.into_mut(),
-            Entry::Vacant(entry) => {
-                let value = call(&entry.key);
-                entry.insert(value)
-            }
-        }
-    }
-
-    /// Gets a reference to the entry's key, either within the map if occupied,
-    /// or else the new key that was used to find the entry.
-    pub fn key(&self) -> &K {
-        match *self {
-            Entry::Occupied(ref entry) => entry.key(),
-            Entry::Vacant(ref entry) => entry.key(),
-        }
-    }
-
-    /// Return the index where the key-value pair exists or will be inserted.
-    pub fn index(&self) -> usize {
-        match *self {
-            Entry::Occupied(ref entry) => entry.index(),
-            Entry::Vacant(ref entry) => entry.index(),
-        }
-    }
-
-    /// Modifies the entry if it is occupied.
-    pub fn and_modify<F>(self, f: F) -> Self
-    where
-        F: FnOnce(&mut V),
-    {
-        match self {
-            Entry::Occupied(mut o) => {
-                f(o.get_mut());
-                Entry::Occupied(o)
-            }
-            x => x,
-        }
-    }
-
-    /// Inserts a default-constructed value in the entry if it is vacant and returns a mutable
-    /// reference to it. Otherwise a mutable reference to an already existent value is returned.
-    ///
-    /// Computes in **O(1)** time (amortized average).
-    pub fn or_default(self) -> &'a mut V
-    where
-        V: Default,
-    {
-        match self {
-            Entry::Occupied(entry) => entry.into_mut(),
-            Entry::Vacant(entry) => entry.insert(V::default()),
-        }
-    }
-}
-
-impl<K: fmt::Debug, V: fmt::Debug> fmt::Debug for Entry<'_, K, V> {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        match *self {
-            Entry::Vacant(ref v) => f.debug_tuple(stringify!(Entry)).field(v).finish(),
-            Entry::Occupied(ref o) => f.debug_tuple(stringify!(Entry)).field(o).finish(),
-        }
-    }
-}
-
-pub use self::raw::OccupiedEntry;
-
-// Extra methods that don't threaten the unsafe encapsulation.
-impl<K, V> OccupiedEntry<'_, K, V> {
-    /// Sets the value of the entry to `value`, and returns the entry's old value.
-    pub fn insert(&mut self, value: V) -> V {
-        replace(self.get_mut(), value)
-    }
-
-    /// Remove the key, value pair stored in the map for this entry, and return the value.
-    ///
-    /// **NOTE:** This is equivalent to `.swap_remove()`.
-    pub fn remove(self) -> V {
-        self.swap_remove()
-    }
-
-    /// Remove the key, value pair stored in the map for this entry, and return the value.
-    ///
-    /// Like `Vec::swap_remove`, the pair is removed by swapping it with the
-    /// last element of the map and popping it off. **This perturbs
-    /// the position of what used to be the last element!**
-    ///
-    /// Computes in **O(1)** time (average).
-    pub fn swap_remove(self) -> V {
-        self.swap_remove_entry().1
-    }
-
-    /// Remove the key, value pair stored in the map for this entry, and return the value.
-    ///
-    /// Like `Vec::remove`, the pair is removed by shifting all of the
-    /// elements that follow it, preserving their relative order.
-    /// **This perturbs the index of all of those elements!**
-    ///
-    /// Computes in **O(n)** time (average).
-    pub fn shift_remove(self) -> V {
-        self.shift_remove_entry().1
-    }
-
-    /// Remove and return the key, value pair stored in the map for this entry
-    ///
-    /// **NOTE:** This is equivalent to `.swap_remove_entry()`.
-    pub fn remove_entry(self) -> (K, V) {
-        self.swap_remove_entry()
-    }
-}
-
-impl<K: fmt::Debug, V: fmt::Debug> fmt::Debug for OccupiedEntry<'_, K, V> {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        f.debug_struct(stringify!(OccupiedEntry))
-            .field("key", self.key())
-            .field("value", self.get())
-            .finish()
-    }
-}
-
-/// A view into a vacant entry in a `IndexMap`.
-/// It is part of the [`Entry`] enum.
-///
-/// [`Entry`]: enum.Entry.html
-pub struct VacantEntry<'a, K, V> {
-    map: &'a mut IndexMapCore<K, V>,
-    hash: HashValue,
-    key: K,
-}
-
-impl<'a, K, V> VacantEntry<'a, K, V> {
-    /// Gets a reference to the key that was used to find the entry.
-    pub fn key(&self) -> &K {
-        &self.key
-    }
-
-    /// Takes ownership of the key, leaving the entry vacant.
-    pub fn into_key(self) -> K {
-        self.key
-    }
-
-    /// Return the index where the key-value pair will be inserted.
-    pub fn index(&self) -> usize {
-        self.map.len()
-    }
-
-    /// Inserts the entry's key and the given value into the map, and returns a mutable reference
-    /// to the value.
-    pub fn insert(self, value: V) -> &'a mut V {
-        let i = self.map.push(self.hash, self.key, value);
-        &mut self.map.entries[i].value
-    }
-}
-
-impl<K: fmt::Debug, V> fmt::Debug for VacantEntry<'_, K, V> {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        f.debug_tuple(stringify!(VacantEntry))
-            .field(self.key())
-            .finish()
-    }
-}
-
 #[test]
 fn assert_send_sync() {
     fn assert_send_sync<T: Send + Sync>() {}
     assert_send_sync::<IndexMapCore<i32, i32>>();
     assert_send_sync::<Entry<'_, i32, i32>>();
+    assert_send_sync::<IndexedEntry<'_, i32, i32>>();
 }
diff --git a/third_party/rust/indexmap/src/map/core/entry.rs b/third_party/rust/indexmap/src/map/core/entry.rs
new file mode 100644
index 0000000000..6c31070788
--- /dev/null
+++ b/third_party/rust/indexmap/src/map/core/entry.rs
@@ -0,0 +1,481 @@
+use super::raw::RawTableEntry;
+use super::IndexMapCore;
+use crate::HashValue;
+use core::{fmt, mem};
+
+impl<K, V> IndexMapCore<K, V> {
+    pub(crate) fn entry(&mut self, hash: HashValue, key: K) -> Entry<'_, K, V>
+    where
+        K: Eq,
+    {
+        match self.raw_entry(hash, |k| *k == key) {
+            Ok(raw) => Entry::Occupied(OccupiedEntry { raw }),
+            Err(map) => Entry::Vacant(VacantEntry { map, hash, key }),
+        }
+    }
+}
+
+/// Entry for an existing key-value pair in an [`IndexMap`][crate::IndexMap]
+/// or a vacant location to insert one.
+pub enum Entry<'a, K, V> {
+    /// Existing slot with equivalent key.
+    Occupied(OccupiedEntry<'a, K, V>),
+    /// Vacant slot (no equivalent key in the map).
+    Vacant(VacantEntry<'a, K, V>),
+}
+
+impl<'a, K, V> Entry<'a, K, V> {
+    /// Return the index where the key-value pair exists or will be inserted.
+    pub fn index(&self) -> usize {
+        match *self {
+            Entry::Occupied(ref entry) => entry.index(),
+            Entry::Vacant(ref entry) => entry.index(),
+        }
+    }
+
+    /// Inserts the given default value in the entry if it is vacant and returns a mutable
+    /// reference to it. Otherwise a mutable reference to an already existent value is returned.
+    ///
+    /// Computes in **O(1)** time (amortized average).
+    pub fn or_insert(self, default: V) -> &'a mut V {
+        match self {
+            Entry::Occupied(entry) => entry.into_mut(),
+            Entry::Vacant(entry) => entry.insert(default),
+        }
+    }
+
+    /// Inserts the result of the `call` function in the entry if it is vacant and returns a mutable
+    /// reference to it. Otherwise a mutable reference to an already existent value is returned.
+    ///
+    /// Computes in **O(1)** time (amortized average).
+    pub fn or_insert_with<F>(self, call: F) -> &'a mut V
+    where
+        F: FnOnce() -> V,
+    {
+        match self {
+            Entry::Occupied(entry) => entry.into_mut(),
+            Entry::Vacant(entry) => entry.insert(call()),
+        }
+    }
+
+    /// Inserts the result of the `call` function with a reference to the entry's key if it is
+    /// vacant, and returns a mutable reference to the new value. Otherwise a mutable reference to
+    /// an already existent value is returned.
+    ///
+    /// Computes in **O(1)** time (amortized average).
+    pub fn or_insert_with_key<F>(self, call: F) -> &'a mut V
+    where
+        F: FnOnce(&K) -> V,
+    {
+        match self {
+            Entry::Occupied(entry) => entry.into_mut(),
+            Entry::Vacant(entry) => {
+                let value = call(&entry.key);
+                entry.insert(value)
+            }
+        }
+    }
+
+    /// Gets a reference to the entry's key, either within the map if occupied,
+    /// or else the new key that was used to find the entry.
+    pub fn key(&self) -> &K {
+        match *self {
+            Entry::Occupied(ref entry) => entry.key(),
+            Entry::Vacant(ref entry) => entry.key(),
+        }
+    }
+
+    /// Modifies the entry if it is occupied.
+    pub fn and_modify<F>(mut self, f: F) -> Self
+    where
+        F: FnOnce(&mut V),
+    {
+        if let Entry::Occupied(entry) = &mut self {
+            f(entry.get_mut());
+        }
+        self
+    }
+
+    /// Inserts a default-constructed value in the entry if it is vacant and returns a mutable
+    /// reference to it. Otherwise a mutable reference to an already existent value is returned.
+    ///
+    /// Computes in **O(1)** time (amortized average).
+    pub fn or_default(self) -> &'a mut V
+    where
+        V: Default,
+    {
+        match self {
+            Entry::Occupied(entry) => entry.into_mut(),
+            Entry::Vacant(entry) => entry.insert(V::default()),
+        }
+    }
+}
+
+impl<K: fmt::Debug, V: fmt::Debug> fmt::Debug for Entry<'_, K, V> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let mut tuple = f.debug_tuple("Entry");
+        match self {
+            Entry::Vacant(v) => tuple.field(v),
+            Entry::Occupied(o) => tuple.field(o),
+        };
+        tuple.finish()
+    }
+}
+
+/// A view into an occupied entry in an [`IndexMap`][crate::IndexMap].
+/// It is part of the [`Entry`] enum.
+pub struct OccupiedEntry<'a, K, V> {
+    raw: RawTableEntry<'a, K, V>,
+}
+
+impl<'a, K, V> OccupiedEntry<'a, K, V> {
+    /// Return the index of the key-value pair
+    #[inline]
+    pub fn index(&self) -> usize {
+        self.raw.index()
+    }
+
+    /// Gets a reference to the entry's key in the map.
+    ///
+    /// Note that this is not the key that was used to find the entry. There may be an observable
+    /// difference if the key type has any distinguishing features outside of `Hash` and `Eq`, like
+    /// extra fields or the memory address of an allocation.
+    pub fn key(&self) -> &K {
+        &self.raw.bucket().key
+    }
+
+    /// Gets a reference to the entry's value in the map.
+    pub fn get(&self) -> &V {
+        &self.raw.bucket().value
+    }
+
+    /// Gets a mutable reference to the entry's value in the map.
+    ///
+    /// If you need a reference which may outlive the destruction of the
+    /// [`Entry`] value, see [`into_mut`][Self::into_mut].
+    pub fn get_mut(&mut self) -> &mut V {
+        &mut self.raw.bucket_mut().value
+    }
+
+    /// Converts into a mutable reference to the entry's value in the map,
+    /// with a lifetime bound to the map itself.
+    pub fn into_mut(self) -> &'a mut V {
+        &mut self.raw.into_bucket().value
+    }
+
+    /// Sets the value of the entry to `value`, and returns the entry's old value.
+    pub fn insert(&mut self, value: V) -> V {
+        mem::replace(self.get_mut(), value)
+    }
+
+    /// Remove the key, value pair stored in the map for this entry, and return the value.
+    ///
+    /// **NOTE:** This is equivalent to [`.swap_remove()`][Self::swap_remove], replacing this
+    /// entry's position with the last element, and it is deprecated in favor of calling that
+    /// explicitly. If you need to preserve the relative order of the keys in the map, use
+    /// [`.shift_remove()`][Self::shift_remove] instead.
+    #[deprecated(note = "`remove` disrupts the map order -- \
+        use `swap_remove` or `shift_remove` for explicit behavior.")]
+    pub fn remove(self) -> V {
+        self.swap_remove()
+    }
+
+    /// Remove the key, value pair stored in the map for this entry, and return the value.
+    ///
+    /// Like [`Vec::swap_remove`][crate::Vec::swap_remove], the pair is removed by swapping it with
+    /// the last element of the map and popping it off.
+    /// **This perturbs the position of what used to be the last element!**
+    ///
+    /// Computes in **O(1)** time (average).
+    pub fn swap_remove(self) -> V {
+        self.swap_remove_entry().1
+    }
+
+    /// Remove the key, value pair stored in the map for this entry, and return the value.
+    ///
+    /// Like [`Vec::remove`][crate::Vec::remove], the pair is removed by shifting all of the
+    /// elements that follow it, preserving their relative order.
+    /// **This perturbs the index of all of those elements!**
+    ///
+    /// Computes in **O(n)** time (average).
+    pub fn shift_remove(self) -> V {
+        self.shift_remove_entry().1
+    }
+
+    /// Remove and return the key, value pair stored in the map for this entry
+    ///
+    /// **NOTE:** This is equivalent to [`.swap_remove_entry()`][Self::swap_remove_entry],
+    /// replacing this entry's position with the last element, and it is deprecated in favor of
+    /// calling that explicitly. If you need to preserve the relative order of the keys in the map,
+    /// use [`.shift_remove_entry()`][Self::shift_remove_entry] instead.
+    #[deprecated(note = "`remove_entry` disrupts the map order -- \
+        use `swap_remove_entry` or `shift_remove_entry` for explicit behavior.")]
+    pub fn remove_entry(self) -> (K, V) {
+        self.swap_remove_entry()
+    }
+
+    /// Remove and return the key, value pair stored in the map for this entry
+    ///
+    /// Like [`Vec::swap_remove`][crate::Vec::swap_remove], the pair is removed by swapping it with
+    /// the last element of the map and popping it off.
+    /// **This perturbs the position of what used to be the last element!**
+    ///
+    /// Computes in **O(1)** time (average).
+    pub fn swap_remove_entry(self) -> (K, V) {
+        let (map, index) = self.raw.remove_index();
+        map.swap_remove_finish(index)
+    }
+
+    /// Remove and return the key, value pair stored in the map for this entry
+    ///
+    /// Like [`Vec::remove`][crate::Vec::remove], the pair is removed by shifting all of the
+    /// elements that follow it, preserving their relative order.
+    /// **This perturbs the index of all of those elements!**
+    ///
+    /// Computes in **O(n)** time (average).
+    pub fn shift_remove_entry(self) -> (K, V) {
+        let (map, index) = self.raw.remove_index();
+        map.shift_remove_finish(index)
+    }
+
+    /// Moves the position of the entry to a new index
+    /// by shifting all other entries in-between.
+    ///
+    /// This is equivalent to [`IndexMap::move_index`][`crate::IndexMap::move_index`]
+    /// coming `from` the current [`.index()`][Self::index].
+    ///
+    /// * If `self.index() < to`, the other pairs will shift down while the targeted pair moves up.
+    /// * If `self.index() > to`, the other pairs will shift up while the targeted pair moves down.
+    ///
+    /// ***Panics*** if `to` is out of bounds.
+    ///
+    /// Computes in **O(n)** time (average).
+    pub fn move_index(self, to: usize) {
+        let (map, index) = self.raw.into_inner();
+        map.move_index(index, to);
+    }
+
+    /// Swaps the position of entry with another.
+    ///
+    /// This is equivalent to [`IndexMap::swap_indices`][`crate::IndexMap::swap_indices`]
+    /// with the current [`.index()`][Self::index] as one of the two being swapped.
+    ///
+    /// ***Panics*** if the `other` index is out of bounds.
+    ///
+    /// Computes in **O(1)** time (average).
+    pub fn swap_indices(self, other: usize) {
+        let (map, index) = self.raw.into_inner();
+        map.swap_indices(index, other)
+    }
+}
+
+impl<K: fmt::Debug, V: fmt::Debug> fmt::Debug for OccupiedEntry<'_, K, V> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_struct("OccupiedEntry")
+            .field("key", self.key())
+            .field("value", self.get())
+            .finish()
+    }
+}
+
+/// A view into a vacant entry in an [`IndexMap`][crate::IndexMap].
+/// It is part of the [`Entry`] enum.
+pub struct VacantEntry<'a, K, V> {
+    map: &'a mut IndexMapCore<K, V>,
+    hash: HashValue,
+    key: K,
+}
+
+impl<'a, K, V> VacantEntry<'a, K, V> {
+    /// Return the index where a key-value pair may be inserted.
+    pub fn index(&self) -> usize {
+        self.map.indices.len()
+    }
+
+    /// Gets a reference to the key that was used to find the entry.
+    pub fn key(&self) -> &K {
+        &self.key
+    }
+
+    /// Takes ownership of the key, leaving the entry vacant.
+    pub fn into_key(self) -> K {
+        self.key
+    }
+
+    /// Inserts the entry's key and the given value into the map, and returns a mutable reference
+    /// to the value.
+    pub fn insert(self, value: V) -> &'a mut V {
+        let Self { map, hash, key } = self;
+        let i = map.insert_unique(hash, key, value);
+        &mut map.entries[i].value
+    }
+
+    /// Inserts the entry's key and the given value into the map at its ordered
+    /// position among sorted keys, and returns the new index and a mutable
+    /// reference to the value.
+    ///
+    /// If the existing keys are **not** already sorted, then the insertion
+    /// index is unspecified (like [`slice::binary_search`]), but the key-value
+    /// pair is inserted at that position regardless.
+    ///
+    /// Computes in **O(n)** time (average).
+    pub fn insert_sorted(self, value: V) -> (usize, &'a mut V)
+    where
+        K: Ord,
+    {
+        let slice = crate::map::Slice::from_slice(&self.map.entries);
+        let i = slice.binary_search_keys(&self.key).unwrap_err();
+        (i, self.shift_insert(i, value))
+    }
+
+    /// Inserts the entry's key and the given value into the map at the given index,
+    /// shifting others to the right, and returns a mutable reference to the value.
+    ///
+    /// ***Panics*** if `index` is out of bounds.
+    ///
+    /// Computes in **O(n)** time (average).
+    pub fn shift_insert(self, index: usize, value: V) -> &'a mut V {
+        let Self { map, hash, key } = self;
+        map.shift_insert_unique(index, hash, key, value);
+        &mut map.entries[index].value
+    }
+}
+
+impl<K: fmt::Debug, V> fmt::Debug for VacantEntry<'_, K, V> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_tuple("VacantEntry").field(self.key()).finish()
+    }
+}
+
+/// A view into an occupied entry in an [`IndexMap`][crate::IndexMap] obtained by index.
+///
+/// This `struct` is created from the [`get_index_entry`][crate::IndexMap::get_index_entry] method.
+pub struct IndexedEntry<'a, K, V> {
+    map: &'a mut IndexMapCore<K, V>,
+    // We have a mutable reference to the map, which keeps the index
+    // valid and pointing to the correct entry.
+    index: usize,
+}
+
+impl<'a, K, V> IndexedEntry<'a, K, V> {
+    pub(crate) fn new(map: &'a mut IndexMapCore<K, V>, index: usize) -> Self {
+        Self { map, index }
+    }
+
+    /// Return the index of the key-value pair
+    #[inline]
+    pub fn index(&self) -> usize {
+        self.index
+    }
+
+    /// Gets a reference to the entry's key in the map.
+    pub fn key(&self) -> &K {
+        &self.map.entries[self.index].key
+    }
+
+    /// Gets a reference to the entry's value in the map.
+    pub fn get(&self) -> &V {
+        &self.map.entries[self.index].value
+    }
+
+    /// Gets a mutable reference to the entry's value in the map.
+    ///
+    /// If you need a reference which may outlive the destruction of the
+    /// `IndexedEntry` value, see [`into_mut`][Self::into_mut].
+    pub fn get_mut(&mut self) -> &mut V {
+        &mut self.map.entries[self.index].value
+    }
+
+    /// Sets the value of the entry to `value`, and returns the entry's old value.
+    pub fn insert(&mut self, value: V) -> V {
+        mem::replace(self.get_mut(), value)
+    }
+
+    /// Converts into a mutable reference to the entry's value in the map,
+    /// with a lifetime bound to the map itself.
+    pub fn into_mut(self) -> &'a mut V {
+        &mut self.map.entries[self.index].value
+    }
+
+    /// Remove and return the key, value pair stored in the map for this entry
+    ///
+    /// Like [`Vec::swap_remove`][crate::Vec::swap_remove], the pair is removed by swapping it with
+    /// the last element of the map and popping it off.
+    /// **This perturbs the position of what used to be the last element!**
+    ///
+    /// Computes in **O(1)** time (average).
+    pub fn swap_remove_entry(self) -> (K, V) {
+        self.map.swap_remove_index(self.index).unwrap()
+    }
+
+    /// Remove and return the key, value pair stored in the map for this entry
+    ///
+    /// Like [`Vec::remove`][crate::Vec::remove], the pair is removed by shifting all of the
+    /// elements that follow it, preserving their relative order.
+    /// **This perturbs the index of all of those elements!**
+    ///
+    /// Computes in **O(n)** time (average).
+    pub fn shift_remove_entry(self) -> (K, V) {
+        self.map.shift_remove_index(self.index).unwrap()
+    }
+
+    /// Remove the key, value pair stored in the map for this entry, and return the value.
+    ///
+    /// Like [`Vec::swap_remove`][crate::Vec::swap_remove], the pair is removed by swapping it with
+    /// the last element of the map and popping it off.
+    /// **This perturbs the position of what used to be the last element!**
+    ///
+    /// Computes in **O(1)** time (average).
+    pub fn swap_remove(self) -> V {
+        self.swap_remove_entry().1
+    }
+
+    /// Remove the key, value pair stored in the map for this entry, and return the value.
+    ///
+    /// Like [`Vec::remove`][crate::Vec::remove], the pair is removed by shifting all of the
+    /// elements that follow it, preserving their relative order.
+    /// **This perturbs the index of all of those elements!**
+    ///
+    /// Computes in **O(n)** time (average).
+    pub fn shift_remove(self) -> V {
+        self.shift_remove_entry().1
+    }
+
+    /// Moves the position of the entry to a new index
+    /// by shifting all other entries in-between.
+    ///
+    /// This is equivalent to [`IndexMap::move_index`][`crate::IndexMap::move_index`]
+    /// coming `from` the current [`.index()`][Self::index].
+    ///
+    /// * If `self.index() < to`, the other pairs will shift down while the targeted pair moves up.
+    /// * If `self.index() > to`, the other pairs will shift up while the targeted pair moves down.
+    ///
+    /// ***Panics*** if `to` is out of bounds.
+    ///
+    /// Computes in **O(n)** time (average).
+    pub fn move_index(self, to: usize) {
+        self.map.move_index(self.index, to);
+    }
+
+    /// Swaps the position of entry with another.
+    ///
+    /// This is equivalent to [`IndexMap::swap_indices`][`crate::IndexMap::swap_indices`]
+    /// with the current [`.index()`][Self::index] as one of the two being swapped.
+    ///
+    /// ***Panics*** if the `other` index is out of bounds.
+    ///
+    /// Computes in **O(1)** time (average).
+    pub fn swap_indices(self, other: usize) {
+        self.map.swap_indices(self.index, other)
+    }
+}
+
+impl<K: fmt::Debug, V: fmt::Debug> fmt::Debug for IndexedEntry<'_, K, V> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_struct("IndexedEntry")
+            .field("index", &self.index)
+            .field("key", self.key())
+            .field("value", self.get())
+            .finish()
+    }
+}
diff --git a/third_party/rust/indexmap/src/map/core/raw.rs b/third_party/rust/indexmap/src/map/core/raw.rs
index bf1672d52a..451994339a 100644
--- a/third_party/rust/indexmap/src/map/core/raw.rs
+++ b/third_party/rust/indexmap/src/map/core/raw.rs
@@ -2,9 +2,7 @@
 //! This module encapsulates the `unsafe` access to `hashbrown::raw::RawTable`,
 //! mostly in dealing with its bucket "pointers".
 
-use super::{equivalent, Bucket, Entry, HashValue, IndexMapCore, VacantEntry};
-use core::fmt;
-use core::mem::replace;
+use super::{equivalent, get_hash, Bucket, HashValue, IndexMapCore};
 use hashbrown::raw::RawTable;
 
 type RawBucket = hashbrown::raw::Bucket<usize>;
@@ -22,11 +20,14 @@ pub(super) fn insert_bulk_no_grow<K, V>(indices: &mut RawTable<usize>, entries:
     }
 }
 
+#[cfg(feature = "test_debug")]
 pub(super) struct DebugIndices<'a>(pub &'a RawTable<usize>);
-impl fmt::Debug for DebugIndices<'_> {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+
+#[cfg(feature = "test_debug")]
+impl core::fmt::Debug for DebugIndices<'_> {
+    fn fmt(&self, f: &mut core::fmt::Formatter<'_>) -> core::fmt::Result {
         // SAFETY: we're not letting any of the buckets escape this function
-        let indices = unsafe { self.0.iter().map(|raw_bucket| raw_bucket.read()) };
+        let indices = unsafe { self.0.iter().map(|raw_bucket| *raw_bucket.as_ref()) };
         f.debug_list().entries(indices).finish()
     }
 }
@@ -38,34 +39,57 @@ impl<K, V> IndexMapCore<K, V> {
         unsafe {
             let offset = end - start;
             for bucket in self.indices.iter() {
-                let i = bucket.read();
-                if i >= end {
-                    bucket.write(i - offset);
-                } else if i >= start {
+                let i = bucket.as_mut();
+                if *i >= end {
+                    *i -= offset;
+                } else if *i >= start {
                     self.indices.erase(bucket);
                 }
             }
         }
     }
 
-    pub(crate) fn entry(&mut self, hash: HashValue, key: K) -> Entry<'_, K, V>
+    /// Search for a key in the table and return `Ok(entry_index)` if found.
+    /// Otherwise, insert the key and return `Err(new_index)`.
+    ///
+    /// Note that hashbrown may resize the table to reserve space for insertion,
+    /// even before checking if it's already present, so this is somewhat biased
+    /// towards new items.
+    pub(crate) fn find_or_insert(&mut self, hash: HashValue, key: &K) -> Result<usize, usize>
     where
         K: Eq,
     {
-        let eq = equivalent(&key, &self.entries);
+        let hash = hash.get();
+        let eq = equivalent(key, &self.entries);
+        let hasher = get_hash(&self.entries);
+        // SAFETY: We're not mutating between find and read/insert.
+        unsafe {
+            match self.indices.find_or_find_insert_slot(hash, eq, hasher) {
+                Ok(raw_bucket) => Ok(*raw_bucket.as_ref()),
+                Err(slot) => {
+                    let index = self.indices.len();
+                    self.indices.insert_in_slot(hash, slot, index);
+                    Err(index)
+                }
+            }
+        }
+    }
+
+    pub(super) fn raw_entry(
+        &mut self,
+        hash: HashValue,
+        mut is_match: impl FnMut(&K) -> bool,
+    ) -> Result<RawTableEntry<'_, K, V>, &mut Self> {
+        let entries = &*self.entries;
+        let eq = move |&i: &usize| is_match(&entries[i].key);
         match self.indices.find(hash.get(), eq) {
             // SAFETY: The entry is created with a live raw bucket, at the same time
             // we have a &mut reference to the map, so it can not be modified further.
-            Some(raw_bucket) => Entry::Occupied(OccupiedEntry {
+            Some(raw_bucket) => Ok(RawTableEntry {
                 map: self,
                 raw_bucket,
-                key,
-            }),
-            None => Entry::Vacant(VacantEntry {
-                map: self,
-                hash,
-                key,
             }),
+            None => Err(self),
         }
     }
 
@@ -74,118 +98,56 @@ impl<K, V> IndexMapCore<K, V> {
         // only the item references that are appropriately bound to `&mut self`.
         unsafe { self.indices.iter().map(|bucket| bucket.as_mut()) }
     }
-
-    /// Return the raw bucket for the given index
-    fn find_index(&self, index: usize) -> RawBucket {
-        // We'll get a "nice" bounds-check from indexing `self.entries`,
-        // and then we expect to find it in the table as well.
-        let hash = self.entries[index].hash.get();
-        self.indices
-            .find(hash, move |&i| i == index)
-            .expect("index not found")
-    }
-
-    pub(crate) fn swap_indices(&mut self, a: usize, b: usize) {
-        // SAFETY: Can't take two `get_mut` references from one table, so we
-        // must use raw buckets to do the swap. This is still safe because we
-        // are locally sure they won't dangle, and we write them individually.
-        unsafe {
-            let raw_bucket_a = self.find_index(a);
-            let raw_bucket_b = self.find_index(b);
-            raw_bucket_a.write(b);
-            raw_bucket_b.write(a);
-        }
-        self.entries.swap(a, b);
-    }
 }
 
-/// A view into an occupied entry in a `IndexMap`.
-/// It is part of the [`Entry`] enum.
-///
-/// [`Entry`]: enum.Entry.html
+/// A view into an occupied raw entry in an `IndexMap`.
 // SAFETY: The lifetime of the map reference also constrains the raw bucket,
 // which is essentially a raw pointer into the map indices.
-pub struct OccupiedEntry<'a, K, V> {
+pub(super) struct RawTableEntry<'a, K, V> {
     map: &'a mut IndexMapCore<K, V>,
     raw_bucket: RawBucket,
-    key: K,
 }
 
 // `hashbrown::raw::Bucket` is only `Send`, not `Sync`.
 // SAFETY: `&self` only accesses the bucket to read it.
-unsafe impl<K: Sync, V: Sync> Sync for OccupiedEntry<'_, K, V> {}
-
-// The parent module also adds methods that don't threaten the unsafe encapsulation.
-impl<'a, K, V> OccupiedEntry<'a, K, V> {
-    /// Gets a reference to the entry's key in the map.
-    ///
-    /// Note that this is not the key that was used to find the entry. There may be an observable
-    /// difference if the key type has any distinguishing features outside of `Hash` and `Eq`, like
-    /// extra fields or the memory address of an allocation.
-    pub fn key(&self) -> &K {
-        &self.map.entries[self.index()].key
-    }
+unsafe impl<K: Sync, V: Sync> Sync for RawTableEntry<'_, K, V> {}
 
-    /// Gets a reference to the entry's value in the map.
-    pub fn get(&self) -> &V {
-        &self.map.entries[self.index()].value
+impl<'a, K, V> RawTableEntry<'a, K, V> {
+    /// Return the index of the key-value pair
+    #[inline]
+    pub(super) fn index(&self) -> usize {
+        // SAFETY: we have `&mut map` keeping the bucket stable
+        unsafe { *self.raw_bucket.as_ref() }
     }
 
-    /// Gets a mutable reference to the entry's value in the map.
-    ///
-    /// If you need a reference which may outlive the destruction of the
-    /// `Entry` value, see `into_mut`.
-    pub fn get_mut(&mut self) -> &mut V {
-        let index = self.index();
-        &mut self.map.entries[index].value
+    #[inline]
+    pub(super) fn bucket(&self) -> &Bucket<K, V> {
+        &self.map.entries[self.index()]
     }
 
-    /// Put the new key in the occupied entry's key slot
-    pub(crate) fn replace_key(self) -> K {
+    #[inline]
+    pub(super) fn bucket_mut(&mut self) -> &mut Bucket<K, V> {
         let index = self.index();
-        let old_key = &mut self.map.entries[index].key;
-        replace(old_key, self.key)
+        &mut self.map.entries[index]
     }
 
-    /// Return the index of the key-value pair
     #[inline]
-    pub fn index(&self) -> usize {
-        // SAFETY: we have &mut map keep keeping the bucket stable
-        unsafe { self.raw_bucket.read() }
-    }
-
-    /// Converts into a mutable reference to the entry's value in the map,
-    /// with a lifetime bound to the map itself.
-    pub fn into_mut(self) -> &'a mut V {
+    pub(super) fn into_bucket(self) -> &'a mut Bucket<K, V> {
         let index = self.index();
-        &mut self.map.entries[index].value
+        &mut self.map.entries[index]
     }
 
-    /// Remove and return the key, value pair stored in the map for this entry
-    ///
-    /// Like `Vec::swap_remove`, the pair is removed by swapping it with the
-    /// last element of the map and popping it off. **This perturbs
-    /// the position of what used to be the last element!**
-    ///
-    /// Computes in **O(1)** time (average).
-    pub fn swap_remove_entry(self) -> (K, V) {
+    /// Remove the index from indices, leaving the actual entries to the caller.
+    pub(super) fn remove_index(self) -> (&'a mut IndexMapCore<K, V>, usize) {
         // SAFETY: This is safe because it can only happen once (self is consumed)
         // and map.indices have not been modified since entry construction
-        let index = unsafe { self.map.indices.remove(self.raw_bucket) };
-        self.map.swap_remove_finish(index)
+        let (index, _slot) = unsafe { self.map.indices.remove(self.raw_bucket) };
+        (self.map, index)
     }
 
-    /// Remove and return the key, value pair stored in the map for this entry
-    ///
-    /// Like `Vec::remove`, the pair is removed by shifting all of the
-    /// elements that follow it, preserving their relative order.
-    /// **This perturbs the index of all of those elements!**
-    ///
-    /// Computes in **O(n)** time (average).
-    pub fn shift_remove_entry(self) -> (K, V) {
-        // SAFETY: This is safe because it can only happen once (self is consumed)
-        // and map.indices have not been modified since entry construction
-        let index = unsafe { self.map.indices.remove(self.raw_bucket) };
-        self.map.shift_remove_finish(index)
+    /// Take no action, just return the index and the original map reference.
+    pub(super) fn into_inner(self) -> (&'a mut IndexMapCore<K, V>, usize) {
+        let index = self.index();
+        (self.map, index)
     }
 }
diff --git a/third_party/rust/indexmap/src/map/core/raw_entry_v1.rs b/third_party/rust/indexmap/src/map/core/raw_entry_v1.rs
new file mode 100644
index 0000000000..87e532d557
--- /dev/null
+++ b/third_party/rust/indexmap/src/map/core/raw_entry_v1.rs
@@ -0,0 +1,652 @@
+//! Opt-in access to the experimental raw entry API.
+//!
+//! This module is designed to mimic the raw entry API of [`HashMap`][std::collections::hash_map],
+//! matching its unstable state as of Rust 1.75. See the tracking issue
+//! [rust#56167](https://github.com/rust-lang/rust/issues/56167) for more details.
+//!
+//! The trait [`RawEntryApiV1`] and the `_v1` suffix on its methods are meant to insulate this for
+//! the future, in case later breaking changes are needed. If the standard library stabilizes its
+//! `hash_raw_entry` feature (or some replacement), matching *inherent* methods will be added to
+//! `IndexMap` without such an opt-in trait.
+
+use super::raw::RawTableEntry;
+use super::IndexMapCore;
+use crate::{Equivalent, HashValue, IndexMap};
+use core::fmt;
+use core::hash::{BuildHasher, Hash, Hasher};
+use core::marker::PhantomData;
+use core::mem;
+
+/// Opt-in access to the experimental raw entry API.
+///
+/// See the [`raw_entry_v1`][self] module documentation for more information.
+pub trait RawEntryApiV1<K, V, S>: private::Sealed {
+    /// Creates a raw immutable entry builder for the [`IndexMap`].
+    ///
+    /// Raw entries provide the lowest level of control for searching and
+    /// manipulating a map. They must be manually initialized with a hash and
+    /// then manually searched.
+    ///
+    /// This is useful for
+    /// * Hash memoization
+    /// * Using a search key that doesn't work with the [`Equivalent`] trait
+    /// * Using custom comparison logic without newtype wrappers
+    ///
+    /// Unless you are in such a situation, higher-level and more foolproof APIs like
+    /// [`get`][IndexMap::get] should be preferred.
+    ///
+    /// Immutable raw entries have very limited use; you might instead want
+    /// [`raw_entry_mut_v1`][Self::raw_entry_mut_v1].
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use core::hash::{BuildHasher, Hash};
+    /// use indexmap::map::{IndexMap, RawEntryApiV1};
+    ///
+    /// let mut map = IndexMap::new();
+    /// map.extend([("a", 100), ("b", 200), ("c", 300)]);
+    ///
+    /// fn compute_hash<K: Hash + ?Sized, S: BuildHasher>(hash_builder: &S, key: &K) -> u64 {
+    ///     use core::hash::Hasher;
+    ///     let mut state = hash_builder.build_hasher();
+    ///     key.hash(&mut state);
+    ///     state.finish()
+    /// }
+    ///
+    /// for k in ["a", "b", "c", "d", "e", "f"] {
+    ///     let hash = compute_hash(map.hasher(), k);
+    ///     let i = map.get_index_of(k);
+    ///     let v = map.get(k);
+    ///     let kv = map.get_key_value(k);
+    ///     let ikv = map.get_full(k);
+    ///
+    ///     println!("Key: {} and value: {:?}", k, v);
+    ///
+    ///     assert_eq!(map.raw_entry_v1().from_key(k), kv);
+    ///     assert_eq!(map.raw_entry_v1().from_hash(hash, |q| *q == k), kv);
+    ///     assert_eq!(map.raw_entry_v1().from_key_hashed_nocheck(hash, k), kv);
+    ///     assert_eq!(map.raw_entry_v1().from_hash_full(hash, |q| *q == k), ikv);
+    ///     assert_eq!(map.raw_entry_v1().index_from_hash(hash, |q| *q == k), i);
+    /// }
+    /// ```
+    fn raw_entry_v1(&self) -> RawEntryBuilder<'_, K, V, S>;
+
+    /// Creates a raw entry builder for the [`IndexMap`].
+    ///
+    /// Raw entries provide the lowest level of control for searching and
+    /// manipulating a map. They must be manually initialized with a hash and
+    /// then manually searched. After this, insertions into a vacant entry
+    /// still require an owned key to be provided.
+    ///
+    /// Raw entries are useful for such exotic situations as:
+    ///
+    /// * Hash memoization
+    /// * Deferring the creation of an owned key until it is known to be required
+    /// * Using a search key that doesn't work with the [`Equivalent`] trait
+    /// * Using custom comparison logic without newtype wrappers
+    ///
+    /// Because raw entries provide much more low-level control, it's much easier
+    /// to put the `IndexMap` into an inconsistent state which, while memory-safe,
+    /// will cause the map to produce seemingly random results. Higher-level and more
+    /// foolproof APIs like [`entry`][IndexMap::entry] should be preferred when possible.
+    ///
+    /// Raw entries give mutable access to the keys. This must not be used
+    /// to modify how the key would compare or hash, as the map will not re-evaluate
+    /// where the key should go, meaning the keys may become "lost" if their
+    /// location does not reflect their state. For instance, if you change a key
+    /// so that the map now contains keys which compare equal, search may start
+    /// acting erratically, with two keys randomly masking each other. Implementations
+    /// are free to assume this doesn't happen (within the limits of memory-safety).
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use core::hash::{BuildHasher, Hash};
+    /// use indexmap::map::{IndexMap, RawEntryApiV1};
+    /// use indexmap::map::raw_entry_v1::RawEntryMut;
+    ///
+    /// let mut map = IndexMap::new();
+    /// map.extend([("a", 100), ("b", 200), ("c", 300)]);
+    ///
+    /// fn compute_hash<K: Hash + ?Sized, S: BuildHasher>(hash_builder: &S, key: &K) -> u64 {
+    ///     use core::hash::Hasher;
+    ///     let mut state = hash_builder.build_hasher();
+    ///     key.hash(&mut state);
+    ///     state.finish()
+    /// }
+    ///
+    /// // Existing key (insert and update)
+    /// match map.raw_entry_mut_v1().from_key("a") {
+    ///     RawEntryMut::Vacant(_) => unreachable!(),
+    ///     RawEntryMut::Occupied(mut view) => {
+    ///         assert_eq!(view.index(), 0);
+    ///         assert_eq!(view.get(), &100);
+    ///         let v = view.get_mut();
+    ///         let new_v = (*v) * 10;
+    ///         *v = new_v;
+    ///         assert_eq!(view.insert(1111), 1000);
+    ///     }
+    /// }
+    ///
+    /// assert_eq!(map["a"], 1111);
+    /// assert_eq!(map.len(), 3);
+    ///
+    /// // Existing key (take)
+    /// let hash = compute_hash(map.hasher(), "c");
+    /// match map.raw_entry_mut_v1().from_key_hashed_nocheck(hash, "c") {
+    ///     RawEntryMut::Vacant(_) => unreachable!(),
+    ///     RawEntryMut::Occupied(view) => {
+    ///         assert_eq!(view.index(), 2);
+    ///         assert_eq!(view.shift_remove_entry(), ("c", 300));
+    ///     }
+    /// }
+    /// assert_eq!(map.raw_entry_v1().from_key("c"), None);
+    /// assert_eq!(map.len(), 2);
+    ///
+    /// // Nonexistent key (insert and update)
+    /// let key = "d";
+    /// let hash = compute_hash(map.hasher(), key);
+    /// match map.raw_entry_mut_v1().from_hash(hash, |q| *q == key) {
+    ///     RawEntryMut::Occupied(_) => unreachable!(),
+    ///     RawEntryMut::Vacant(view) => {
+    ///         assert_eq!(view.index(), 2);
+    ///         let (k, value) = view.insert("d", 4000);
+    ///         assert_eq!((*k, *value), ("d", 4000));
+    ///         *value = 40000;
+    ///     }
+    /// }
+    /// assert_eq!(map["d"], 40000);
+    /// assert_eq!(map.len(), 3);
+    ///
+    /// match map.raw_entry_mut_v1().from_hash(hash, |q| *q == key) {
+    ///     RawEntryMut::Vacant(_) => unreachable!(),
+    ///     RawEntryMut::Occupied(view) => {
+    ///         assert_eq!(view.index(), 2);
+    ///         assert_eq!(view.swap_remove_entry(), ("d", 40000));
+    ///     }
+    /// }
+    /// assert_eq!(map.get("d"), None);
+    /// assert_eq!(map.len(), 2);
+    /// ```
+    fn raw_entry_mut_v1(&mut self) -> RawEntryBuilderMut<'_, K, V, S>;
+}
+
+impl<K, V, S> RawEntryApiV1<K, V, S> for IndexMap<K, V, S> {
+    fn raw_entry_v1(&self) -> RawEntryBuilder<'_, K, V, S> {
+        RawEntryBuilder { map: self }
+    }
+
+    fn raw_entry_mut_v1(&mut self) -> RawEntryBuilderMut<'_, K, V, S> {
+        RawEntryBuilderMut { map: self }
+    }
+}
+
+/// A builder for computing where in an [`IndexMap`] a key-value pair would be stored.
+///
+/// This `struct` is created by the [`IndexMap::raw_entry_v1`] method, provided by the
+/// [`RawEntryApiV1`] trait. See its documentation for more.
+pub struct RawEntryBuilder<'a, K, V, S> {
+    map: &'a IndexMap<K, V, S>,
+}
+
+impl<K, V, S> fmt::Debug for RawEntryBuilder<'_, K, V, S> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_struct("RawEntryBuilder").finish_non_exhaustive()
+    }
+}
+
+impl<'a, K, V, S> RawEntryBuilder<'a, K, V, S> {
+    /// Access an entry by key.
+    pub fn from_key<Q>(self, key: &Q) -> Option<(&'a K, &'a V)>
+    where
+        S: BuildHasher,
+        Q: ?Sized + Hash + Equivalent<K>,
+    {
+        self.map.get_key_value(key)
+    }
+
+    /// Access an entry by a key and its hash.
+    pub fn from_key_hashed_nocheck<Q>(self, hash: u64, key: &Q) -> Option<(&'a K, &'a V)>
+    where
+        Q: ?Sized + Equivalent<K>,
+    {
+        let hash = HashValue(hash as usize);
+        let i = self.map.core.get_index_of(hash, key)?;
+        self.map.get_index(i)
+    }
+
+    /// Access an entry by hash.
+    pub fn from_hash<F>(self, hash: u64, is_match: F) -> Option<(&'a K, &'a V)>
+    where
+        F: FnMut(&K) -> bool,
+    {
+        let map = self.map;
+        let i = self.index_from_hash(hash, is_match)?;
+        map.get_index(i)
+    }
+
+    /// Access an entry by hash, including its index.
+    pub fn from_hash_full<F>(self, hash: u64, is_match: F) -> Option<(usize, &'a K, &'a V)>
+    where
+        F: FnMut(&K) -> bool,
+    {
+        let map = self.map;
+        let i = self.index_from_hash(hash, is_match)?;
+        let (key, value) = map.get_index(i)?;
+        Some((i, key, value))
+    }
+
+    /// Access the index of an entry by hash.
+    pub fn index_from_hash<F>(self, hash: u64, mut is_match: F) -> Option<usize>
+    where
+        F: FnMut(&K) -> bool,
+    {
+        let hash = HashValue(hash as usize);
+        let entries = &*self.map.core.entries;
+        let eq = move |&i: &usize| is_match(&entries[i].key);
+        self.map.core.indices.get(hash.get(), eq).copied()
+    }
+}
+
+/// A builder for computing where in an [`IndexMap`] a key-value pair would be stored.
+///
+/// This `struct` is created by the [`IndexMap::raw_entry_mut_v1`] method, provided by the
+/// [`RawEntryApiV1`] trait. See its documentation for more.
+pub struct RawEntryBuilderMut<'a, K, V, S> {
+    map: &'a mut IndexMap<K, V, S>,
+}
+
+impl<K, V, S> fmt::Debug for RawEntryBuilderMut<'_, K, V, S> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_struct("RawEntryBuilderMut").finish_non_exhaustive()
+    }
+}
+
+impl<'a, K, V, S> RawEntryBuilderMut<'a, K, V, S> {
+    /// Access an entry by key.
+    pub fn from_key<Q>(self, key: &Q) -> RawEntryMut<'a, K, V, S>
+    where
+        S: BuildHasher,
+        Q: ?Sized + Hash + Equivalent<K>,
+    {
+        let hash = self.map.hash(key);
+        self.from_key_hashed_nocheck(hash.get(), key)
+    }
+
+    /// Access an entry by a key and its hash.
+    pub fn from_key_hashed_nocheck<Q>(self, hash: u64, key: &Q) -> RawEntryMut<'a, K, V, S>
+    where
+        Q: ?Sized + Equivalent<K>,
+    {
+        self.from_hash(hash, |k| Q::equivalent(key, k))
+    }
+
+    /// Access an entry by hash.
+    pub fn from_hash<F>(self, hash: u64, is_match: F) -> RawEntryMut<'a, K, V, S>
+    where
+        F: FnMut(&K) -> bool,
+    {
+        let hash = HashValue(hash as usize);
+        match self.map.core.raw_entry(hash, is_match) {
+            Ok(raw) => RawEntryMut::Occupied(RawOccupiedEntryMut {
+                raw,
+                hash_builder: PhantomData,
+            }),
+            Err(map) => RawEntryMut::Vacant(RawVacantEntryMut {
+                map,
+                hash_builder: &self.map.hash_builder,
+            }),
+        }
+    }
+}
+
+/// Raw entry for an existing key-value pair or a vacant location to
+/// insert one.
+pub enum RawEntryMut<'a, K, V, S> {
+    /// Existing slot with equivalent key.
+    Occupied(RawOccupiedEntryMut<'a, K, V, S>),
+    /// Vacant slot (no equivalent key in the map).
+    Vacant(RawVacantEntryMut<'a, K, V, S>),
+}
+
+impl<K: fmt::Debug, V: fmt::Debug, S> fmt::Debug for RawEntryMut<'_, K, V, S> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let mut tuple = f.debug_tuple("RawEntryMut");
+        match self {
+            Self::Vacant(v) => tuple.field(v),
+            Self::Occupied(o) => tuple.field(o),
+        };
+        tuple.finish()
+    }
+}
+
+impl<'a, K, V, S> RawEntryMut<'a, K, V, S> {
+    /// Return the index where the key-value pair exists or may be inserted.
+    #[inline]
+    pub fn index(&self) -> usize {
+        match self {
+            Self::Occupied(entry) => entry.index(),
+            Self::Vacant(entry) => entry.index(),
+        }
+    }
+
+    /// Inserts the given default key and value in the entry if it is vacant and returns mutable
+    /// references to them. Otherwise mutable references to an already existent pair are returned.
+    pub fn or_insert(self, default_key: K, default_value: V) -> (&'a mut K, &'a mut V)
+    where
+        K: Hash,
+        S: BuildHasher,
+    {
+        match self {
+            Self::Occupied(entry) => entry.into_key_value_mut(),
+            Self::Vacant(entry) => entry.insert(default_key, default_value),
+        }
+    }
+
+    /// Inserts the result of the `call` function in the entry if it is vacant and returns mutable
+    /// references to them. Otherwise mutable references to an already existent pair are returned.
+    pub fn or_insert_with<F>(self, call: F) -> (&'a mut K, &'a mut V)
+    where
+        F: FnOnce() -> (K, V),
+        K: Hash,
+        S: BuildHasher,
+    {
+        match self {
+            Self::Occupied(entry) => entry.into_key_value_mut(),
+            Self::Vacant(entry) => {
+                let (key, value) = call();
+                entry.insert(key, value)
+            }
+        }
+    }
+
+    /// Modifies the entry if it is occupied.
+    pub fn and_modify<F>(mut self, f: F) -> Self
+    where
+        F: FnOnce(&mut K, &mut V),
+    {
+        if let Self::Occupied(entry) = &mut self {
+            let (k, v) = entry.get_key_value_mut();
+            f(k, v);
+        }
+        self
+    }
+}
+
+/// A raw view into an occupied entry in an [`IndexMap`].
+/// It is part of the [`RawEntryMut`] enum.
+pub struct RawOccupiedEntryMut<'a, K, V, S> {
+    raw: RawTableEntry<'a, K, V>,
+    hash_builder: PhantomData<&'a S>,
+}
+
+impl<K: fmt::Debug, V: fmt::Debug, S> fmt::Debug for RawOccupiedEntryMut<'_, K, V, S> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_struct("RawOccupiedEntryMut")
+            .field("key", self.key())
+            .field("value", self.get())
+            .finish_non_exhaustive()
+    }
+}
+
+impl<'a, K, V, S> RawOccupiedEntryMut<'a, K, V, S> {
+    /// Return the index of the key-value pair
+    #[inline]
+    pub fn index(&self) -> usize {
+        self.raw.index()
+    }
+
+    /// Gets a reference to the entry's key in the map.
+    ///
+    /// Note that this is not the key that was used to find the entry. There may be an observable
+    /// difference if the key type has any distinguishing features outside of `Hash` and `Eq`, like
+    /// extra fields or the memory address of an allocation.
+    pub fn key(&self) -> &K {
+        &self.raw.bucket().key
+    }
+
+    /// Gets a mutable reference to the entry's key in the map.
+    ///
+    /// Note that this is not the key that was used to find the entry. There may be an observable
+    /// difference if the key type has any distinguishing features outside of `Hash` and `Eq`, like
+    /// extra fields or the memory address of an allocation.
+    pub fn key_mut(&mut self) -> &mut K {
+        &mut self.raw.bucket_mut().key
+    }
+
+    /// Converts into a mutable reference to the entry's key in the map,
+    /// with a lifetime bound to the map itself.
+    ///
+    /// Note that this is not the key that was used to find the entry. There may be an observable
+    /// difference if the key type has any distinguishing features outside of `Hash` and `Eq`, like
+    /// extra fields or the memory address of an allocation.
+    pub fn into_key(self) -> &'a mut K {
+        &mut self.raw.into_bucket().key
+    }
+
+    /// Gets a reference to the entry's value in the map.
+    pub fn get(&self) -> &V {
+        &self.raw.bucket().value
+    }
+
+    /// Gets a mutable reference to the entry's value in the map.
+    ///
+    /// If you need a reference which may outlive the destruction of the
+    /// [`RawEntryMut`] value, see [`into_mut`][Self::into_mut].
+    pub fn get_mut(&mut self) -> &mut V {
+        &mut self.raw.bucket_mut().value
+    }
+
+    /// Converts into a mutable reference to the entry's value in the map,
+    /// with a lifetime bound to the map itself.
+    pub fn into_mut(self) -> &'a mut V {
+        &mut self.raw.into_bucket().value
+    }
+
+    /// Gets a reference to the entry's key and value in the map.
+    pub fn get_key_value(&self) -> (&K, &V) {
+        self.raw.bucket().refs()
+    }
+
+    /// Gets a reference to the entry's key and value in the map.
+    pub fn get_key_value_mut(&mut self) -> (&mut K, &mut V) {
+        self.raw.bucket_mut().muts()
+    }
+
+    /// Converts into a mutable reference to the entry's key and value in the map,
+    /// with a lifetime bound to the map itself.
+    pub fn into_key_value_mut(self) -> (&'a mut K, &'a mut V) {
+        self.raw.into_bucket().muts()
+    }
+
+    /// Sets the value of the entry, and returns the entry's old value.
+    pub fn insert(&mut self, value: V) -> V {
+        mem::replace(self.get_mut(), value)
+    }
+
+    /// Sets the key of the entry, and returns the entry's old key.
+    pub fn insert_key(&mut self, key: K) -> K {
+        mem::replace(self.key_mut(), key)
+    }
+
+    /// Remove the key, value pair stored in the map for this entry, and return the value.
+    ///
+    /// **NOTE:** This is equivalent to [`.swap_remove()`][Self::swap_remove], replacing this
+    /// entry's position with the last element, and it is deprecated in favor of calling that
+    /// explicitly. If you need to preserve the relative order of the keys in the map, use
+    /// [`.shift_remove()`][Self::shift_remove] instead.
+    #[deprecated(note = "`remove` disrupts the map order -- \
+        use `swap_remove` or `shift_remove` for explicit behavior.")]
+    pub fn remove(self) -> V {
+        self.swap_remove()
+    }
+
+    /// Remove the key, value pair stored in the map for this entry, and return the value.
+    ///
+    /// Like [`Vec::swap_remove`][crate::Vec::swap_remove], the pair is removed by swapping it with
+    /// the last element of the map and popping it off.
+    /// **This perturbs the position of what used to be the last element!**
+    ///
+    /// Computes in **O(1)** time (average).
+    pub fn swap_remove(self) -> V {
+        self.swap_remove_entry().1
+    }
+
+    /// Remove the key, value pair stored in the map for this entry, and return the value.
+    ///
+    /// Like [`Vec::remove`][crate::Vec::remove], the pair is removed by shifting all of the
+    /// elements that follow it, preserving their relative order.
+    /// **This perturbs the index of all of those elements!**
+    ///
+    /// Computes in **O(n)** time (average).
+    pub fn shift_remove(self) -> V {
+        self.shift_remove_entry().1
+    }
+
+    /// Remove and return the key, value pair stored in the map for this entry
+    ///
+    /// **NOTE:** This is equivalent to [`.swap_remove_entry()`][Self::swap_remove_entry],
+    /// replacing this entry's position with the last element, and it is deprecated in favor of
+    /// calling that explicitly. If you need to preserve the relative order of the keys in the map,
+    /// use [`.shift_remove_entry()`][Self::shift_remove_entry] instead.
+    #[deprecated(note = "`remove_entry` disrupts the map order -- \
+        use `swap_remove_entry` or `shift_remove_entry` for explicit behavior.")]
+    pub fn remove_entry(self) -> (K, V) {
+        self.swap_remove_entry()
+    }
+
+    /// Remove and return the key, value pair stored in the map for this entry
+    ///
+    /// Like [`Vec::swap_remove`][crate::Vec::swap_remove], the pair is removed by swapping it with
+    /// the last element of the map and popping it off.
+    /// **This perturbs the position of what used to be the last element!**
+    ///
+    /// Computes in **O(1)** time (average).
+    pub fn swap_remove_entry(self) -> (K, V) {
+        let (map, index) = self.raw.remove_index();
+        map.swap_remove_finish(index)
+    }
+
+    /// Remove and return the key, value pair stored in the map for this entry
+    ///
+    /// Like [`Vec::remove`][crate::Vec::remove], the pair is removed by shifting all of the
+    /// elements that follow it, preserving their relative order.
+    /// **This perturbs the index of all of those elements!**
+    ///
+    /// Computes in **O(n)** time (average).
+    pub fn shift_remove_entry(self) -> (K, V) {
+        let (map, index) = self.raw.remove_index();
+        map.shift_remove_finish(index)
+    }
+
+    /// Moves the position of the entry to a new index
+    /// by shifting all other entries in-between.
+    ///
+    /// This is equivalent to [`IndexMap::move_index`]
+    /// coming `from` the current [`.index()`][Self::index].
+    ///
+    /// * If `self.index() < to`, the other pairs will shift down while the targeted pair moves up.
+    /// * If `self.index() > to`, the other pairs will shift up while the targeted pair moves down.
+    ///
+    /// ***Panics*** if `to` is out of bounds.
+    ///
+    /// Computes in **O(n)** time (average).
+    pub fn move_index(self, to: usize) {
+        let (map, index) = self.raw.into_inner();
+        map.move_index(index, to);
+    }
+
+    /// Swaps the position of entry with another.
+    ///
+    /// This is equivalent to [`IndexMap::swap_indices`]
+    /// with the current [`.index()`][Self::index] as one of the two being swapped.
+    ///
+    /// ***Panics*** if the `other` index is out of bounds.
+    ///
+    /// Computes in **O(1)** time (average).
+    pub fn swap_indices(self, other: usize) {
+        let (map, index) = self.raw.into_inner();
+        map.swap_indices(index, other)
+    }
+}
+
+/// A view into a vacant raw entry in an [`IndexMap`].
+/// It is part of the [`RawEntryMut`] enum.
+pub struct RawVacantEntryMut<'a, K, V, S> {
+    map: &'a mut IndexMapCore<K, V>,
+    hash_builder: &'a S,
+}
+
+impl<K, V, S> fmt::Debug for RawVacantEntryMut<'_, K, V, S> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_struct("RawVacantEntryMut").finish_non_exhaustive()
+    }
+}
+
+impl<'a, K, V, S> RawVacantEntryMut<'a, K, V, S> {
+    /// Return the index where a key-value pair may be inserted.
+    pub fn index(&self) -> usize {
+        self.map.indices.len()
+    }
+
+    /// Inserts the given key and value into the map,
+    /// and returns mutable references to them.
+    pub fn insert(self, key: K, value: V) -> (&'a mut K, &'a mut V)
+    where
+        K: Hash,
+        S: BuildHasher,
+    {
+        let mut h = self.hash_builder.build_hasher();
+        key.hash(&mut h);
+        self.insert_hashed_nocheck(h.finish(), key, value)
+    }
+
+    /// Inserts the given key and value into the map with the provided hash,
+    /// and returns mutable references to them.
+    pub fn insert_hashed_nocheck(self, hash: u64, key: K, value: V) -> (&'a mut K, &'a mut V) {
+        let hash = HashValue(hash as usize);
+        let i = self.map.insert_unique(hash, key, value);
+        self.map.entries[i].muts()
+    }
+
+    /// Inserts the given key and value into the map at the given index,
+    /// shifting others to the right, and returns mutable references to them.
+    ///
+    /// ***Panics*** if `index` is out of bounds.
+    ///
+    /// Computes in **O(n)** time (average).
+    pub fn shift_insert(self, index: usize, key: K, value: V) -> (&'a mut K, &'a mut V)
+    where
+        K: Hash,
+        S: BuildHasher,
+    {
+        let mut h = self.hash_builder.build_hasher();
+        key.hash(&mut h);
+        self.shift_insert_hashed_nocheck(index, h.finish(), key, value)
+    }
+
+    /// Inserts the given key and value into the map with the provided hash
+    /// at the given index, and returns mutable references to them.
+    ///
+    /// ***Panics*** if `index` is out of bounds.
+    ///
+    /// Computes in **O(n)** time (average).
+    pub fn shift_insert_hashed_nocheck(
+        self,
+        index: usize,
+        hash: u64,
+        key: K,
+        value: V,
+    ) -> (&'a mut K, &'a mut V) {
+        let hash = HashValue(hash as usize);
+        self.map.shift_insert_unique(index, hash, key, value);
+        self.map.entries[index].muts()
+    }
+}
+
+mod private {
+    pub trait Sealed {}
+
+    impl<K, V, S> Sealed for super::IndexMap<K, V, S> {}
+}
diff --git a/third_party/rust/indexmap/src/map/iter.rs b/third_party/rust/indexmap/src/map/iter.rs
new file mode 100644
index 0000000000..1ec3703cfb
--- /dev/null
+++ b/third_party/rust/indexmap/src/map/iter.rs
@@ -0,0 +1,713 @@
+use super::core::IndexMapCore;
+use super::{Bucket, Entries, IndexMap, Slice};
+
+use alloc::vec::{self, Vec};
+use core::fmt;
+use core::hash::{BuildHasher, Hash};
+use core::iter::FusedIterator;
+use core::ops::{Index, RangeBounds};
+use core::slice;
+
+impl<'a, K, V, S> IntoIterator for &'a IndexMap<K, V, S> {
+    type Item = (&'a K, &'a V);
+    type IntoIter = Iter<'a, K, V>;
+
+    fn into_iter(self) -> Self::IntoIter {
+        self.iter()
+    }
+}
+
+impl<'a, K, V, S> IntoIterator for &'a mut IndexMap<K, V, S> {
+    type Item = (&'a K, &'a mut V);
+    type IntoIter = IterMut<'a, K, V>;
+
+    fn into_iter(self) -> Self::IntoIter {
+        self.iter_mut()
+    }
+}
+
+impl<K, V, S> IntoIterator for IndexMap<K, V, S> {
+    type Item = (K, V);
+    type IntoIter = IntoIter<K, V>;
+
+    fn into_iter(self) -> Self::IntoIter {
+        IntoIter::new(self.into_entries())
+    }
+}
+
+/// An iterator over the entries of an [`IndexMap`].
+///
+/// This `struct` is created by the [`IndexMap::iter`] method.
+/// See its documentation for more.
+pub struct Iter<'a, K, V> {
+    iter: slice::Iter<'a, Bucket<K, V>>,
+}
+
+impl<'a, K, V> Iter<'a, K, V> {
+    pub(super) fn new(entries: &'a [Bucket<K, V>]) -> Self {
+        Self {
+            iter: entries.iter(),
+        }
+    }
+
+    /// Returns a slice of the remaining entries in the iterator.
+    pub fn as_slice(&self) -> &'a Slice<K, V> {
+        Slice::from_slice(self.iter.as_slice())
+    }
+}
+
+impl<'a, K, V> Iterator for Iter<'a, K, V> {
+    type Item = (&'a K, &'a V);
+
+    iterator_methods!(Bucket::refs);
+}
+
+impl<K, V> DoubleEndedIterator for Iter<'_, K, V> {
+    double_ended_iterator_methods!(Bucket::refs);
+}
+
+impl<K, V> ExactSizeIterator for Iter<'_, K, V> {
+    fn len(&self) -> usize {
+        self.iter.len()
+    }
+}
+
+impl<K, V> FusedIterator for Iter<'_, K, V> {}
+
+// FIXME(#26925) Remove in favor of `#[derive(Clone)]`
+impl<K, V> Clone for Iter<'_, K, V> {
+    fn clone(&self) -> Self {
+        Iter {
+            iter: self.iter.clone(),
+        }
+    }
+}
+
+impl<K: fmt::Debug, V: fmt::Debug> fmt::Debug for Iter<'_, K, V> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_list().entries(self.clone()).finish()
+    }
+}
+
+impl<K, V> Default for Iter<'_, K, V> {
+    fn default() -> Self {
+        Self { iter: [].iter() }
+    }
+}
+
+/// A mutable iterator over the entries of an [`IndexMap`].
+///
+/// This `struct` is created by the [`IndexMap::iter_mut`] method.
+/// See its documentation for more.
+pub struct IterMut<'a, K, V> {
+    iter: slice::IterMut<'a, Bucket<K, V>>,
+}
+
+impl<'a, K, V> IterMut<'a, K, V> {
+    pub(super) fn new(entries: &'a mut [Bucket<K, V>]) -> Self {
+        Self {
+            iter: entries.iter_mut(),
+        }
+    }
+
+    /// Returns a slice of the remaining entries in the iterator.
+    pub fn as_slice(&self) -> &Slice<K, V> {
+        Slice::from_slice(self.iter.as_slice())
+    }
+
+    /// Returns a mutable slice of the remaining entries in the iterator.
+    ///
+    /// To avoid creating `&mut` references that alias, this is forced to consume the iterator.
+    pub fn into_slice(self) -> &'a mut Slice<K, V> {
+        Slice::from_mut_slice(self.iter.into_slice())
+    }
+}
+
+impl<'a, K, V> Iterator for IterMut<'a, K, V> {
+    type Item = (&'a K, &'a mut V);
+
+    iterator_methods!(Bucket::ref_mut);
+}
+
+impl<K, V> DoubleEndedIterator for IterMut<'_, K, V> {
+    double_ended_iterator_methods!(Bucket::ref_mut);
+}
+
+impl<K, V> ExactSizeIterator for IterMut<'_, K, V> {
+    fn len(&self) -> usize {
+        self.iter.len()
+    }
+}
+
+impl<K, V> FusedIterator for IterMut<'_, K, V> {}
+
+impl<K: fmt::Debug, V: fmt::Debug> fmt::Debug for IterMut<'_, K, V> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let iter = self.iter.as_slice().iter().map(Bucket::refs);
+        f.debug_list().entries(iter).finish()
+    }
+}
+
+impl<K, V> Default for IterMut<'_, K, V> {
+    fn default() -> Self {
+        Self {
+            iter: [].iter_mut(),
+        }
+    }
+}
+
+/// An owning iterator over the entries of an [`IndexMap`].
+///
+/// This `struct` is created by the [`IndexMap::into_iter`] method
+/// (provided by the [`IntoIterator`] trait). See its documentation for more.
+pub struct IntoIter<K, V> {
+    iter: vec::IntoIter<Bucket<K, V>>,
+}
+
+impl<K, V> IntoIter<K, V> {
+    pub(super) fn new(entries: Vec<Bucket<K, V>>) -> Self {
+        Self {
+            iter: entries.into_iter(),
+        }
+    }
+
+    /// Returns a slice of the remaining entries in the iterator.
+    pub fn as_slice(&self) -> &Slice<K, V> {
+        Slice::from_slice(self.iter.as_slice())
+    }
+
+    /// Returns a mutable slice of the remaining entries in the iterator.
+    pub fn as_mut_slice(&mut self) -> &mut Slice<K, V> {
+        Slice::from_mut_slice(self.iter.as_mut_slice())
+    }
+}
+
+impl<K, V> Iterator for IntoIter<K, V> {
+    type Item = (K, V);
+
+    iterator_methods!(Bucket::key_value);
+}
+
+impl<K, V> DoubleEndedIterator for IntoIter<K, V> {
+    double_ended_iterator_methods!(Bucket::key_value);
+}
+
+impl<K, V> ExactSizeIterator for IntoIter<K, V> {
+    fn len(&self) -> usize {
+        self.iter.len()
+    }
+}
+
+impl<K, V> FusedIterator for IntoIter<K, V> {}
+
+impl<K: fmt::Debug, V: fmt::Debug> fmt::Debug for IntoIter<K, V> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let iter = self.iter.as_slice().iter().map(Bucket::refs);
+        f.debug_list().entries(iter).finish()
+    }
+}
+
+impl<K, V> Default for IntoIter<K, V> {
+    fn default() -> Self {
+        Self {
+            iter: Vec::new().into_iter(),
+        }
+    }
+}
+
+/// A draining iterator over the entries of an [`IndexMap`].
+///
+/// This `struct` is created by the [`IndexMap::drain`] method.
+/// See its documentation for more.
+pub struct Drain<'a, K, V> {
+    iter: vec::Drain<'a, Bucket<K, V>>,
+}
+
+impl<'a, K, V> Drain<'a, K, V> {
+    pub(super) fn new(iter: vec::Drain<'a, Bucket<K, V>>) -> Self {
+        Self { iter }
+    }
+
+    /// Returns a slice of the remaining entries in the iterator.
+    pub fn as_slice(&self) -> &Slice<K, V> {
+        Slice::from_slice(self.iter.as_slice())
+    }
+}
+
+impl<K, V> Iterator for Drain<'_, K, V> {
+    type Item = (K, V);
+
+    iterator_methods!(Bucket::key_value);
+}
+
+impl<K, V> DoubleEndedIterator for Drain<'_, K, V> {
+    double_ended_iterator_methods!(Bucket::key_value);
+}
+
+impl<K, V> ExactSizeIterator for Drain<'_, K, V> {
+    fn len(&self) -> usize {
+        self.iter.len()
+    }
+}
+
+impl<K, V> FusedIterator for Drain<'_, K, V> {}
+
+impl<K: fmt::Debug, V: fmt::Debug> fmt::Debug for Drain<'_, K, V> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let iter = self.iter.as_slice().iter().map(Bucket::refs);
+        f.debug_list().entries(iter).finish()
+    }
+}
+
+/// An iterator over the keys of an [`IndexMap`].
+///
+/// This `struct` is created by the [`IndexMap::keys`] method.
+/// See its documentation for more.
+pub struct Keys<'a, K, V> {
+    iter: slice::Iter<'a, Bucket<K, V>>,
+}
+
+impl<'a, K, V> Keys<'a, K, V> {
+    pub(super) fn new(entries: &'a [Bucket<K, V>]) -> Self {
+        Self {
+            iter: entries.iter(),
+        }
+    }
+}
+
+impl<'a, K, V> Iterator for Keys<'a, K, V> {
+    type Item = &'a K;
+
+    iterator_methods!(Bucket::key_ref);
+}
+
+impl<K, V> DoubleEndedIterator for Keys<'_, K, V> {
+    double_ended_iterator_methods!(Bucket::key_ref);
+}
+
+impl<K, V> ExactSizeIterator for Keys<'_, K, V> {
+    fn len(&self) -> usize {
+        self.iter.len()
+    }
+}
+
+impl<K, V> FusedIterator for Keys<'_, K, V> {}
+
+// FIXME(#26925) Remove in favor of `#[derive(Clone)]`
+impl<K, V> Clone for Keys<'_, K, V> {
+    fn clone(&self) -> Self {
+        Keys {
+            iter: self.iter.clone(),
+        }
+    }
+}
+
+impl<K: fmt::Debug, V> fmt::Debug for Keys<'_, K, V> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_list().entries(self.clone()).finish()
+    }
+}
+
+impl<K, V> Default for Keys<'_, K, V> {
+    fn default() -> Self {
+        Self { iter: [].iter() }
+    }
+}
+
+/// Access [`IndexMap`] keys at indexed positions.
+///
+/// While [`Index<usize> for IndexMap`][values] accesses a map's values,
+/// indexing through [`IndexMap::keys`] offers an alternative to access a map's
+/// keys instead.
+///
+/// [values]: IndexMap#impl-Index<usize>-for-IndexMap<K,+V,+S>
+///
+/// Since `Keys` is also an iterator, consuming items from the iterator will
+/// offset the effective indexes. Similarly, if `Keys` is obtained from
+/// [`Slice::keys`], indexes will be interpreted relative to the position of
+/// that slice.
+///
+/// # Examples
+///
+/// ```
+/// use indexmap::IndexMap;
+///
+/// let mut map = IndexMap::new();
+/// for word in "Lorem ipsum dolor sit amet".split_whitespace() {
+///     map.insert(word.to_lowercase(), word.to_uppercase());
+/// }
+///
+/// assert_eq!(map[0], "LOREM");
+/// assert_eq!(map.keys()[0], "lorem");
+/// assert_eq!(map[1], "IPSUM");
+/// assert_eq!(map.keys()[1], "ipsum");
+///
+/// map.reverse();
+/// assert_eq!(map.keys()[0], "amet");
+/// assert_eq!(map.keys()[1], "sit");
+///
+/// map.sort_keys();
+/// assert_eq!(map.keys()[0], "amet");
+/// assert_eq!(map.keys()[1], "dolor");
+///
+/// // Advancing the iterator will offset the indexing
+/// let mut keys = map.keys();
+/// assert_eq!(keys[0], "amet");
+/// assert_eq!(keys.next().map(|s| &**s), Some("amet"));
+/// assert_eq!(keys[0], "dolor");
+/// assert_eq!(keys[1], "ipsum");
+///
+/// // Slices may have an offset as well
+/// let slice = &map[2..];
+/// assert_eq!(slice[0], "IPSUM");
+/// assert_eq!(slice.keys()[0], "ipsum");
+/// ```
+///
+/// ```should_panic
+/// use indexmap::IndexMap;
+///
+/// let mut map = IndexMap::new();
+/// map.insert("foo", 1);
+/// println!("{:?}", map.keys()[10]); // panics!
+/// ```
+impl<'a, K, V> Index<usize> for Keys<'a, K, V> {
+    type Output = K;
+
+    /// Returns a reference to the key at the supplied `index`.
+    ///
+    /// ***Panics*** if `index` is out of bounds.
+    fn index(&self, index: usize) -> &K {
+        &self.iter.as_slice()[index].key
+    }
+}
+
+/// An owning iterator over the keys of an [`IndexMap`].
+///
+/// This `struct` is created by the [`IndexMap::into_keys`] method.
+/// See its documentation for more.
+pub struct IntoKeys<K, V> {
+    iter: vec::IntoIter<Bucket<K, V>>,
+}
+
+impl<K, V> IntoKeys<K, V> {
+    pub(super) fn new(entries: Vec<Bucket<K, V>>) -> Self {
+        Self {
+            iter: entries.into_iter(),
+        }
+    }
+}
+
+impl<K, V> Iterator for IntoKeys<K, V> {
+    type Item = K;
+
+    iterator_methods!(Bucket::key);
+}
+
+impl<K, V> DoubleEndedIterator for IntoKeys<K, V> {
+    double_ended_iterator_methods!(Bucket::key);
+}
+
+impl<K, V> ExactSizeIterator for IntoKeys<K, V> {
+    fn len(&self) -> usize {
+        self.iter.len()
+    }
+}
+
+impl<K, V> FusedIterator for IntoKeys<K, V> {}
+
+impl<K: fmt::Debug, V> fmt::Debug for IntoKeys<K, V> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let iter = self.iter.as_slice().iter().map(Bucket::key_ref);
+        f.debug_list().entries(iter).finish()
+    }
+}
+
+impl<K, V> Default for IntoKeys<K, V> {
+    fn default() -> Self {
+        Self {
+            iter: Vec::new().into_iter(),
+        }
+    }
+}
+
+/// An iterator over the values of an [`IndexMap`].
+///
+/// This `struct` is created by the [`IndexMap::values`] method.
+/// See its documentation for more.
+pub struct Values<'a, K, V> {
+    iter: slice::Iter<'a, Bucket<K, V>>,
+}
+
+impl<'a, K, V> Values<'a, K, V> {
+    pub(super) fn new(entries: &'a [Bucket<K, V>]) -> Self {
+        Self {
+            iter: entries.iter(),
+        }
+    }
+}
+
+impl<'a, K, V> Iterator for Values<'a, K, V> {
+    type Item = &'a V;
+
+    iterator_methods!(Bucket::value_ref);
+}
+
+impl<K, V> DoubleEndedIterator for Values<'_, K, V> {
+    double_ended_iterator_methods!(Bucket::value_ref);
+}
+
+impl<K, V> ExactSizeIterator for Values<'_, K, V> {
+    fn len(&self) -> usize {
+        self.iter.len()
+    }
+}
+
+impl<K, V> FusedIterator for Values<'_, K, V> {}
+
+// FIXME(#26925) Remove in favor of `#[derive(Clone)]`
+impl<K, V> Clone for Values<'_, K, V> {
+    fn clone(&self) -> Self {
+        Values {
+            iter: self.iter.clone(),
+        }
+    }
+}
+
+impl<K, V: fmt::Debug> fmt::Debug for Values<'_, K, V> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_list().entries(self.clone()).finish()
+    }
+}
+
+impl<K, V> Default for Values<'_, K, V> {
+    fn default() -> Self {
+        Self { iter: [].iter() }
+    }
+}
+
+/// A mutable iterator over the values of an [`IndexMap`].
+///
+/// This `struct` is created by the [`IndexMap::values_mut`] method.
+/// See its documentation for more.
+pub struct ValuesMut<'a, K, V> {
+    iter: slice::IterMut<'a, Bucket<K, V>>,
+}
+
+impl<'a, K, V> ValuesMut<'a, K, V> {
+    pub(super) fn new(entries: &'a mut [Bucket<K, V>]) -> Self {
+        Self {
+            iter: entries.iter_mut(),
+        }
+    }
+}
+
+impl<'a, K, V> Iterator for ValuesMut<'a, K, V> {
+    type Item = &'a mut V;
+
+    iterator_methods!(Bucket::value_mut);
+}
+
+impl<K, V> DoubleEndedIterator for ValuesMut<'_, K, V> {
+    double_ended_iterator_methods!(Bucket::value_mut);
+}
+
+impl<K, V> ExactSizeIterator for ValuesMut<'_, K, V> {
+    fn len(&self) -> usize {
+        self.iter.len()
+    }
+}
+
+impl<K, V> FusedIterator for ValuesMut<'_, K, V> {}
+
+impl<K, V: fmt::Debug> fmt::Debug for ValuesMut<'_, K, V> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let iter = self.iter.as_slice().iter().map(Bucket::value_ref);
+        f.debug_list().entries(iter).finish()
+    }
+}
+
+impl<K, V> Default for ValuesMut<'_, K, V> {
+    fn default() -> Self {
+        Self {
+            iter: [].iter_mut(),
+        }
+    }
+}
+
+/// An owning iterator over the values of an [`IndexMap`].
+///
+/// This `struct` is created by the [`IndexMap::into_values`] method.
+/// See its documentation for more.
+pub struct IntoValues<K, V> {
+    iter: vec::IntoIter<Bucket<K, V>>,
+}
+
+impl<K, V> IntoValues<K, V> {
+    pub(super) fn new(entries: Vec<Bucket<K, V>>) -> Self {
+        Self {
+            iter: entries.into_iter(),
+        }
+    }
+}
+
+impl<K, V> Iterator for IntoValues<K, V> {
+    type Item = V;
+
+    iterator_methods!(Bucket::value);
+}
+
+impl<K, V> DoubleEndedIterator for IntoValues<K, V> {
+    double_ended_iterator_methods!(Bucket::value);
+}
+
+impl<K, V> ExactSizeIterator for IntoValues<K, V> {
+    fn len(&self) -> usize {
+        self.iter.len()
+    }
+}
+
+impl<K, V> FusedIterator for IntoValues<K, V> {}
+
+impl<K, V: fmt::Debug> fmt::Debug for IntoValues<K, V> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let iter = self.iter.as_slice().iter().map(Bucket::value_ref);
+        f.debug_list().entries(iter).finish()
+    }
+}
+
+impl<K, V> Default for IntoValues<K, V> {
+    fn default() -> Self {
+        Self {
+            iter: Vec::new().into_iter(),
+        }
+    }
+}
+
+/// A splicing iterator for `IndexMap`.
+///
+/// This `struct` is created by [`IndexMap::splice()`].
+/// See its documentation for more.
+pub struct Splice<'a, I, K, V, S>
+where
+    I: Iterator<Item = (K, V)>,
+    K: Hash + Eq,
+    S: BuildHasher,
+{
+    map: &'a mut IndexMap<K, V, S>,
+    tail: IndexMapCore<K, V>,
+    drain: vec::IntoIter<Bucket<K, V>>,
+    replace_with: I,
+}
+
+impl<'a, I, K, V, S> Splice<'a, I, K, V, S>
+where
+    I: Iterator<Item = (K, V)>,
+    K: Hash + Eq,
+    S: BuildHasher,
+{
+    pub(super) fn new<R>(map: &'a mut IndexMap<K, V, S>, range: R, replace_with: I) -> Self
+    where
+        R: RangeBounds<usize>,
+    {
+        let (tail, drain) = map.core.split_splice(range);
+        Self {
+            map,
+            tail,
+            drain,
+            replace_with,
+        }
+    }
+}
+
+impl<I, K, V, S> Drop for Splice<'_, I, K, V, S>
+where
+    I: Iterator<Item = (K, V)>,
+    K: Hash + Eq,
+    S: BuildHasher,
+{
+    fn drop(&mut self) {
+        // Finish draining unconsumed items. We don't strictly *have* to do this
+        // manually, since we already split it into separate memory, but it will
+        // match the drop order of `vec::Splice` items this way.
+        let _ = self.drain.nth(usize::MAX);
+
+        // Now insert all the new items. If a key matches an existing entry, it
+        // keeps the original position and only replaces the value, like `insert`.
+        while let Some((key, value)) = self.replace_with.next() {
+            // Since the tail is disjoint, we can try to update it first,
+            // or else insert (update or append) the primary map.
+            let hash = self.map.hash(&key);
+            if let Some(i) = self.tail.get_index_of(hash, &key) {
+                self.tail.as_entries_mut()[i].value = value;
+            } else {
+                self.map.core.insert_full(hash, key, value);
+            }
+        }
+
+        // Finally, re-append the tail
+        self.map.core.append_unchecked(&mut self.tail);
+    }
+}
+
+impl<I, K, V, S> Iterator for Splice<'_, I, K, V, S>
+where
+    I: Iterator<Item = (K, V)>,
+    K: Hash + Eq,
+    S: BuildHasher,
+{
+    type Item = (K, V);
+
+    fn next(&mut self) -> Option<Self::Item> {
+        self.drain.next().map(Bucket::key_value)
+    }
+
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        self.drain.size_hint()
+    }
+}
+
+impl<I, K, V, S> DoubleEndedIterator for Splice<'_, I, K, V, S>
+where
+    I: Iterator<Item = (K, V)>,
+    K: Hash + Eq,
+    S: BuildHasher,
+{
+    fn next_back(&mut self) -> Option<Self::Item> {
+        self.drain.next_back().map(Bucket::key_value)
+    }
+}
+
+impl<I, K, V, S> ExactSizeIterator for Splice<'_, I, K, V, S>
+where
+    I: Iterator<Item = (K, V)>,
+    K: Hash + Eq,
+    S: BuildHasher,
+{
+    fn len(&self) -> usize {
+        self.drain.len()
+    }
+}
+
+impl<I, K, V, S> FusedIterator for Splice<'_, I, K, V, S>
+where
+    I: Iterator<Item = (K, V)>,
+    K: Hash + Eq,
+    S: BuildHasher,
+{
+}
+
+impl<'a, I, K, V, S> fmt::Debug for Splice<'a, I, K, V, S>
+where
+    I: fmt::Debug + Iterator<Item = (K, V)>,
+    K: fmt::Debug + Hash + Eq,
+    V: fmt::Debug,
+    S: BuildHasher,
+{
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        // Follow `vec::Splice` in only printing the drain and replacement
+        f.debug_struct("Splice")
+            .field("drain", &self.drain)
+            .field("replace_with", &self.replace_with)
+            .finish()
+    }
+}
diff --git a/third_party/rust/indexmap/src/map/mutable.rs b/third_party/rust/indexmap/src/map/mutable.rs
new file mode 100644
index 0000000000..7df325948f
--- /dev/null
+++ b/third_party/rust/indexmap/src/map/mutable.rs
@@ -0,0 +1,87 @@
+use core::hash::{BuildHasher, Hash};
+
+use super::{Bucket, Entries, Equivalent, IndexMap};
+
+/// Opt-in mutable access to [`IndexMap`] keys.
+///
+/// These methods expose `&mut K`, mutable references to the key as it is stored
+/// in the map.
+/// You are allowed to modify the keys in the map **if the modification
+/// does not change the key’s hash and equality**.
+///
+/// If keys are modified erroneously, you can no longer look them up.
+/// This is sound (memory safe) but a logical error hazard (just like
+/// implementing `PartialEq`, `Eq`, or `Hash` incorrectly would be).
+///
+/// `use` this trait to enable its methods for `IndexMap`.
+///
+/// This trait is sealed and cannot be implemented for types outside this crate.
+pub trait MutableKeys: private::Sealed {
+    type Key;
+    type Value;
+
+    /// Return item index, mutable reference to key and value
+    ///
+    /// Computes in **O(1)** time (average).
+    fn get_full_mut2<Q>(&mut self, key: &Q) -> Option<(usize, &mut Self::Key, &mut Self::Value)>
+    where
+        Q: ?Sized + Hash + Equivalent<Self::Key>;
+
+    /// Return mutable reference to key and value at an index.
+    ///
+    /// Valid indices are *0 <= index < self.len()*
+    ///
+    /// Computes in **O(1)** time.
+    fn get_index_mut2(&mut self, index: usize) -> Option<(&mut Self::Key, &mut Self::Value)>;
+
+    /// Scan through each key-value pair in the map and keep those where the
+    /// closure `keep` returns `true`.
+    ///
+    /// The elements are visited in order, and remaining elements keep their
+    /// order.
+    ///
+    /// Computes in **O(n)** time (average).
+    fn retain2<F>(&mut self, keep: F)
+    where
+        F: FnMut(&mut Self::Key, &mut Self::Value) -> bool;
+}
+
+/// Opt-in mutable access to [`IndexMap`] keys.
+///
+/// See [`MutableKeys`] for more information.
+impl<K, V, S> MutableKeys for IndexMap<K, V, S>
+where
+    S: BuildHasher,
+{
+    type Key = K;
+    type Value = V;
+
+    fn get_full_mut2<Q>(&mut self, key: &Q) -> Option<(usize, &mut K, &mut V)>
+    where
+        Q: ?Sized + Hash + Equivalent<K>,
+    {
+        if let Some(i) = self.get_index_of(key) {
+            let entry = &mut self.as_entries_mut()[i];
+            Some((i, &mut entry.key, &mut entry.value))
+        } else {
+            None
+        }
+    }
+
+    fn get_index_mut2(&mut self, index: usize) -> Option<(&mut K, &mut V)> {
+        self.as_entries_mut().get_mut(index).map(Bucket::muts)
+    }
+
+    fn retain2<F>(&mut self, keep: F)
+    where
+        F: FnMut(&mut K, &mut V) -> bool,
+    {
+        self.core.retain_in_order(keep);
+    }
+}
+
+mod private {
+    pub trait Sealed {}
+
+    impl<K, V, S> Sealed for super::IndexMap<K, V, S> {}
+}
diff --git a/third_party/rust/indexmap/src/serde_seq.rs b/third_party/rust/indexmap/src/map/serde_seq.rs
index d326a02e37..602ae7dc74 100644
--- a/third_party/rust/indexmap/src/serde_seq.rs
+++ b/third_party/rust/indexmap/src/map/serde_seq.rs
@@ -1,4 +1,4 @@
-//! Functions to serialize and deserialize an `IndexMap` as an ordered sequence.
+//! Functions to serialize and deserialize an [`IndexMap`] as an ordered sequence.
 //!
 //! The default `serde` implementation serializes `IndexMap` as a normal map,
 //! but there is no guarantee that serialization formats will preserve the order
@@ -12,13 +12,11 @@
 //! # use serde_derive::{Deserialize, Serialize};
 //! #[derive(Deserialize, Serialize)]
 //! struct Data {
-//!     #[serde(with = "indexmap::serde_seq")]
+//!     #[serde(with = "indexmap::map::serde_seq")]
 //!     map: IndexMap<i32, u64>,
 //!     // ...
 //! }
 //! ```
-//!
-//! Requires crate feature `"serde"` or `"serde-1"`
 
 use serde::de::{Deserialize, Deserializer, SeqAccess, Visitor};
 use serde::ser::{Serialize, Serializer};
@@ -27,29 +25,59 @@ use core::fmt::{self, Formatter};
 use core::hash::{BuildHasher, Hash};
 use core::marker::PhantomData;
 
+use crate::map::Slice as MapSlice;
+use crate::serde::cautious_capacity;
+use crate::set::Slice as SetSlice;
 use crate::IndexMap;
 
-/// Serializes an `IndexMap` as an ordered sequence.
+/// Serializes a [`map::Slice`][MapSlice] as an ordered sequence.
 ///
-/// This function may be used in a field attribute for deriving `Serialize`:
+/// This behaves like [`crate::map::serde_seq`] for `IndexMap`, serializing a sequence
+/// of `(key, value)` pairs, rather than as a map that might not preserve order.
+impl<K, V> Serialize for MapSlice<K, V>
+where
+    K: Serialize,
+    V: Serialize,
+{
+    fn serialize<T>(&self, serializer: T) -> Result<T::Ok, T::Error>
+    where
+        T: Serializer,
+    {
+        serializer.collect_seq(self)
+    }
+}
+
+/// Serializes a [`set::Slice`][SetSlice] as an ordered sequence.
+impl<T> Serialize for SetSlice<T>
+where
+    T: Serialize,
+{
+    fn serialize<Se>(&self, serializer: Se) -> Result<Se::Ok, Se::Error>
+    where
+        Se: Serializer,
+    {
+        serializer.collect_seq(self)
+    }
+}
+
+/// Serializes an [`IndexMap`] as an ordered sequence.
+///
+/// This function may be used in a field attribute for deriving [`Serialize`]:
 ///
 /// ```
 /// # use indexmap::IndexMap;
 /// # use serde_derive::Serialize;
 /// #[derive(Serialize)]
 /// struct Data {
-///     #[serde(serialize_with = "indexmap::serde_seq::serialize")]
+///     #[serde(serialize_with = "indexmap::map::serde_seq::serialize")]
 ///     map: IndexMap<i32, u64>,
 ///     // ...
 /// }
 /// ```
-///
-/// Requires crate feature `"serde"` or `"serde-1"`
 pub fn serialize<K, V, S, T>(map: &IndexMap<K, V, S>, serializer: T) -> Result<T::Ok, T::Error>
 where
-    K: Serialize + Hash + Eq,
+    K: Serialize,
     V: Serialize,
-    S: BuildHasher,
     T: Serializer,
 {
     serializer.collect_seq(map)
@@ -74,7 +102,7 @@ where
     where
         A: SeqAccess<'de>,
     {
-        let capacity = seq.size_hint().unwrap_or(0);
+        let capacity = cautious_capacity::<K, V>(seq.size_hint());
         let mut map = IndexMap::with_capacity_and_hasher(capacity, S::default());
 
         while let Some((key, value)) = seq.next_element()? {
@@ -85,22 +113,20 @@ where
     }
 }
 
-/// Deserializes an `IndexMap` from an ordered sequence.
+/// Deserializes an [`IndexMap`] from an ordered sequence.
 ///
-/// This function may be used in a field attribute for deriving `Deserialize`:
+/// This function may be used in a field attribute for deriving [`Deserialize`]:
 ///
 /// ```
 /// # use indexmap::IndexMap;
 /// # use serde_derive::Deserialize;
 /// #[derive(Deserialize)]
 /// struct Data {
-///     #[serde(deserialize_with = "indexmap::serde_seq::deserialize")]
+///     #[serde(deserialize_with = "indexmap::map::serde_seq::deserialize")]
 ///     map: IndexMap<i32, u64>,
 ///     // ...
 /// }
 /// ```
-///
-/// Requires crate feature `"serde"` or `"serde-1"`
 pub fn deserialize<'de, D, K, V, S>(deserializer: D) -> Result<IndexMap<K, V, S>, D::Error>
 where
     D: Deserializer<'de>,
diff --git a/third_party/rust/indexmap/src/map/slice.rs b/third_party/rust/indexmap/src/map/slice.rs
new file mode 100644
index 0000000000..b2f00f4807
--- /dev/null
+++ b/third_party/rust/indexmap/src/map/slice.rs
@@ -0,0 +1,539 @@
+use super::{
+    Bucket, Entries, IndexMap, IntoIter, IntoKeys, IntoValues, Iter, IterMut, Keys, Values,
+    ValuesMut,
+};
+use crate::util::try_simplify_range;
+
+use alloc::boxed::Box;
+use alloc::vec::Vec;
+use core::cmp::Ordering;
+use core::fmt;
+use core::hash::{Hash, Hasher};
+use core::ops::{self, Bound, Index, IndexMut, RangeBounds};
+
+/// A dynamically-sized slice of key-value pairs in an [`IndexMap`].
+///
+/// This supports indexed operations much like a `[(K, V)]` slice,
+/// but not any hashed operations on the map keys.
+///
+/// Unlike `IndexMap`, `Slice` does consider the order for [`PartialEq`]
+/// and [`Eq`], and it also implements [`PartialOrd`], [`Ord`], and [`Hash`].
+#[repr(transparent)]
+pub struct Slice<K, V> {
+    pub(crate) entries: [Bucket<K, V>],
+}
+
+// SAFETY: `Slice<K, V>` is a transparent wrapper around `[Bucket<K, V>]`,
+// and reference lifetimes are bound together in function signatures.
+#[allow(unsafe_code)]
+impl<K, V> Slice<K, V> {
+    pub(super) const fn from_slice(entries: &[Bucket<K, V>]) -> &Self {
+        unsafe { &*(entries as *const [Bucket<K, V>] as *const Self) }
+    }
+
+    pub(super) fn from_mut_slice(entries: &mut [Bucket<K, V>]) -> &mut Self {
+        unsafe { &mut *(entries as *mut [Bucket<K, V>] as *mut Self) }
+    }
+
+    pub(super) fn from_boxed(entries: Box<[Bucket<K, V>]>) -> Box<Self> {
+        unsafe { Box::from_raw(Box::into_raw(entries) as *mut Self) }
+    }
+
+    fn into_boxed(self: Box<Self>) -> Box<[Bucket<K, V>]> {
+        unsafe { Box::from_raw(Box::into_raw(self) as *mut [Bucket<K, V>]) }
+    }
+}
+
+impl<K, V> Slice<K, V> {
+    pub(crate) fn into_entries(self: Box<Self>) -> Vec<Bucket<K, V>> {
+        self.into_boxed().into_vec()
+    }
+
+    /// Returns an empty slice.
+    pub const fn new<'a>() -> &'a Self {
+        Self::from_slice(&[])
+    }
+
+    /// Returns an empty mutable slice.
+    pub fn new_mut<'a>() -> &'a mut Self {
+        Self::from_mut_slice(&mut [])
+    }
+
+    /// Return the number of key-value pairs in the map slice.
+    #[inline]
+    pub const fn len(&self) -> usize {
+        self.entries.len()
+    }
+
+    /// Returns true if the map slice contains no elements.
+    #[inline]
+    pub const fn is_empty(&self) -> bool {
+        self.entries.is_empty()
+    }
+
+    /// Get a key-value pair by index.
+    ///
+    /// Valid indices are *0 <= index < self.len()*
+    pub fn get_index(&self, index: usize) -> Option<(&K, &V)> {
+        self.entries.get(index).map(Bucket::refs)
+    }
+
+    /// Get a key-value pair by index, with mutable access to the value.
+    ///
+    /// Valid indices are *0 <= index < self.len()*
+    pub fn get_index_mut(&mut self, index: usize) -> Option<(&K, &mut V)> {
+        self.entries.get_mut(index).map(Bucket::ref_mut)
+    }
+
+    /// Returns a slice of key-value pairs in the given range of indices.
+    ///
+    /// Valid indices are *0 <= index < self.len()*
+    pub fn get_range<R: RangeBounds<usize>>(&self, range: R) -> Option<&Self> {
+        let range = try_simplify_range(range, self.entries.len())?;
+        self.entries.get(range).map(Slice::from_slice)
+    }
+
+    /// Returns a mutable slice of key-value pairs in the given range of indices.
+    ///
+    /// Valid indices are *0 <= index < self.len()*
+    pub fn get_range_mut<R: RangeBounds<usize>>(&mut self, range: R) -> Option<&mut Self> {
+        let range = try_simplify_range(range, self.entries.len())?;
+        self.entries.get_mut(range).map(Slice::from_mut_slice)
+    }
+
+    /// Get the first key-value pair.
+    pub fn first(&self) -> Option<(&K, &V)> {
+        self.entries.first().map(Bucket::refs)
+    }
+
+    /// Get the first key-value pair, with mutable access to the value.
+    pub fn first_mut(&mut self) -> Option<(&K, &mut V)> {
+        self.entries.first_mut().map(Bucket::ref_mut)
+    }
+
+    /// Get the last key-value pair.
+    pub fn last(&self) -> Option<(&K, &V)> {
+        self.entries.last().map(Bucket::refs)
+    }
+
+    /// Get the last key-value pair, with mutable access to the value.
+    pub fn last_mut(&mut self) -> Option<(&K, &mut V)> {
+        self.entries.last_mut().map(Bucket::ref_mut)
+    }
+
+    /// Divides one slice into two at an index.
+    ///
+    /// ***Panics*** if `index > len`.
+    pub fn split_at(&self, index: usize) -> (&Self, &Self) {
+        let (first, second) = self.entries.split_at(index);
+        (Self::from_slice(first), Self::from_slice(second))
+    }
+
+    /// Divides one mutable slice into two at an index.
+    ///
+    /// ***Panics*** if `index > len`.
+    pub fn split_at_mut(&mut self, index: usize) -> (&mut Self, &mut Self) {
+        let (first, second) = self.entries.split_at_mut(index);
+        (Self::from_mut_slice(first), Self::from_mut_slice(second))
+    }
+
+    /// Returns the first key-value pair and the rest of the slice,
+    /// or `None` if it is empty.
+    pub fn split_first(&self) -> Option<((&K, &V), &Self)> {
+        if let [first, rest @ ..] = &self.entries {
+            Some((first.refs(), Self::from_slice(rest)))
+        } else {
+            None
+        }
+    }
+
+    /// Returns the first key-value pair and the rest of the slice,
+    /// with mutable access to the value, or `None` if it is empty.
+    pub fn split_first_mut(&mut self) -> Option<((&K, &mut V), &mut Self)> {
+        if let [first, rest @ ..] = &mut self.entries {
+            Some((first.ref_mut(), Self::from_mut_slice(rest)))
+        } else {
+            None
+        }
+    }
+
+    /// Returns the last key-value pair and the rest of the slice,
+    /// or `None` if it is empty.
+    pub fn split_last(&self) -> Option<((&K, &V), &Self)> {
+        if let [rest @ .., last] = &self.entries {
+            Some((last.refs(), Self::from_slice(rest)))
+        } else {
+            None
+        }
+    }
+
+    /// Returns the last key-value pair and the rest of the slice,
+    /// with mutable access to the value, or `None` if it is empty.
+    pub fn split_last_mut(&mut self) -> Option<((&K, &mut V), &mut Self)> {
+        if let [rest @ .., last] = &mut self.entries {
+            Some((last.ref_mut(), Self::from_mut_slice(rest)))
+        } else {
+            None
+        }
+    }
+
+    /// Return an iterator over the key-value pairs of the map slice.
+    pub fn iter(&self) -> Iter<'_, K, V> {
+        Iter::new(&self.entries)
+    }
+
+    /// Return an iterator over the key-value pairs of the map slice.
+    pub fn iter_mut(&mut self) -> IterMut<'_, K, V> {
+        IterMut::new(&mut self.entries)
+    }
+
+    /// Return an iterator over the keys of the map slice.
+    pub fn keys(&self) -> Keys<'_, K, V> {
+        Keys::new(&self.entries)
+    }
+
+    /// Return an owning iterator over the keys of the map slice.
+    pub fn into_keys(self: Box<Self>) -> IntoKeys<K, V> {
+        IntoKeys::new(self.into_entries())
+    }
+
+    /// Return an iterator over the values of the map slice.
+    pub fn values(&self) -> Values<'_, K, V> {
+        Values::new(&self.entries)
+    }
+
+    /// Return an iterator over mutable references to the the values of the map slice.
+    pub fn values_mut(&mut self) -> ValuesMut<'_, K, V> {
+        ValuesMut::new(&mut self.entries)
+    }
+
+    /// Return an owning iterator over the values of the map slice.
+    pub fn into_values(self: Box<Self>) -> IntoValues<K, V> {
+        IntoValues::new(self.into_entries())
+    }
+
+    /// Search over a sorted map for a key.
+    ///
+    /// Returns the position where that key is present, or the position where it can be inserted to
+    /// maintain the sort. See [`slice::binary_search`] for more details.
+    ///
+    /// Computes in **O(log(n))** time, which is notably less scalable than looking the key up in
+    /// the map this is a slice from using [`IndexMap::get_index_of`], but this can also position
+    /// missing keys.
+    pub fn binary_search_keys(&self, x: &K) -> Result<usize, usize>
+    where
+        K: Ord,
+    {
+        self.binary_search_by(|p, _| p.cmp(x))
+    }
+
+    /// Search over a sorted map with a comparator function.
+    ///
+    /// Returns the position where that value is present, or the position where it can be inserted
+    /// to maintain the sort. See [`slice::binary_search_by`] for more details.
+    ///
+    /// Computes in **O(log(n))** time.
+    #[inline]
+    pub fn binary_search_by<'a, F>(&'a self, mut f: F) -> Result<usize, usize>
+    where
+        F: FnMut(&'a K, &'a V) -> Ordering,
+    {
+        self.entries.binary_search_by(move |a| f(&a.key, &a.value))
+    }
+
+    /// Search over a sorted map with an extraction function.
+    ///
+    /// Returns the position where that value is present, or the position where it can be inserted
+    /// to maintain the sort. See [`slice::binary_search_by_key`] for more details.
+    ///
+    /// Computes in **O(log(n))** time.
+    #[inline]
+    pub fn binary_search_by_key<'a, B, F>(&'a self, b: &B, mut f: F) -> Result<usize, usize>
+    where
+        F: FnMut(&'a K, &'a V) -> B,
+        B: Ord,
+    {
+        self.binary_search_by(|k, v| f(k, v).cmp(b))
+    }
+
+    /// Returns the index of the partition point of a sorted map according to the given predicate
+    /// (the index of the first element of the second partition).
+    ///
+    /// See [`slice::partition_point`] for more details.
+    ///
+    /// Computes in **O(log(n))** time.
+    #[must_use]
+    pub fn partition_point<P>(&self, mut pred: P) -> usize
+    where
+        P: FnMut(&K, &V) -> bool,
+    {
+        self.entries
+            .partition_point(move |a| pred(&a.key, &a.value))
+    }
+}
+
+impl<'a, K, V> IntoIterator for &'a Slice<K, V> {
+    type IntoIter = Iter<'a, K, V>;
+    type Item = (&'a K, &'a V);
+
+    fn into_iter(self) -> Self::IntoIter {
+        self.iter()
+    }
+}
+
+impl<'a, K, V> IntoIterator for &'a mut Slice<K, V> {
+    type IntoIter = IterMut<'a, K, V>;
+    type Item = (&'a K, &'a mut V);
+
+    fn into_iter(self) -> Self::IntoIter {
+        self.iter_mut()
+    }
+}
+
+impl<K, V> IntoIterator for Box<Slice<K, V>> {
+    type IntoIter = IntoIter<K, V>;
+    type Item = (K, V);
+
+    fn into_iter(self) -> Self::IntoIter {
+        IntoIter::new(self.into_entries())
+    }
+}
+
+impl<K, V> Default for &'_ Slice<K, V> {
+    fn default() -> Self {
+        Slice::from_slice(&[])
+    }
+}
+
+impl<K, V> Default for &'_ mut Slice<K, V> {
+    fn default() -> Self {
+        Slice::from_mut_slice(&mut [])
+    }
+}
+
+impl<K, V> Default for Box<Slice<K, V>> {
+    fn default() -> Self {
+        Slice::from_boxed(Box::default())
+    }
+}
+
+impl<K: Clone, V: Clone> Clone for Box<Slice<K, V>> {
+    fn clone(&self) -> Self {
+        Slice::from_boxed(self.entries.to_vec().into_boxed_slice())
+    }
+}
+
+impl<K: Copy, V: Copy> From<&Slice<K, V>> for Box<Slice<K, V>> {
+    fn from(slice: &Slice<K, V>) -> Self {
+        Slice::from_boxed(Box::from(&slice.entries))
+    }
+}
+
+impl<K: fmt::Debug, V: fmt::Debug> fmt::Debug for Slice<K, V> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_list().entries(self).finish()
+    }
+}
+
+impl<K: PartialEq, V: PartialEq> PartialEq for Slice<K, V> {
+    fn eq(&self, other: &Self) -> bool {
+        self.len() == other.len() && self.iter().eq(other)
+    }
+}
+
+impl<K: Eq, V: Eq> Eq for Slice<K, V> {}
+
+impl<K: PartialOrd, V: PartialOrd> PartialOrd for Slice<K, V> {
+    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+        self.iter().partial_cmp(other)
+    }
+}
+
+impl<K: Ord, V: Ord> Ord for Slice<K, V> {
+    fn cmp(&self, other: &Self) -> Ordering {
+        self.iter().cmp(other)
+    }
+}
+
+impl<K: Hash, V: Hash> Hash for Slice<K, V> {
+    fn hash<H: Hasher>(&self, state: &mut H) {
+        self.len().hash(state);
+        for (key, value) in self {
+            key.hash(state);
+            value.hash(state);
+        }
+    }
+}
+
+impl<K, V> Index<usize> for Slice<K, V> {
+    type Output = V;
+
+    fn index(&self, index: usize) -> &V {
+        &self.entries[index].value
+    }
+}
+
+impl<K, V> IndexMut<usize> for Slice<K, V> {
+    fn index_mut(&mut self, index: usize) -> &mut V {
+        &mut self.entries[index].value
+    }
+}
+
+// We can't have `impl<I: RangeBounds<usize>> Index<I>` because that conflicts
+// both upstream with `Index<usize>` and downstream with `Index<&Q>`.
+// Instead, we repeat the implementations for all the core range types.
+macro_rules! impl_index {
+    ($($range:ty),*) => {$(
+        impl<K, V, S> Index<$range> for IndexMap<K, V, S> {
+            type Output = Slice<K, V>;
+
+            fn index(&self, range: $range) -> &Self::Output {
+                Slice::from_slice(&self.as_entries()[range])
+            }
+        }
+
+        impl<K, V, S> IndexMut<$range> for IndexMap<K, V, S> {
+            fn index_mut(&mut self, range: $range) -> &mut Self::Output {
+                Slice::from_mut_slice(&mut self.as_entries_mut()[range])
+            }
+        }
+
+        impl<K, V> Index<$range> for Slice<K, V> {
+            type Output = Slice<K, V>;
+
+            fn index(&self, range: $range) -> &Self {
+                Self::from_slice(&self.entries[range])
+            }
+        }
+
+        impl<K, V> IndexMut<$range> for Slice<K, V> {
+            fn index_mut(&mut self, range: $range) -> &mut Self {
+                Self::from_mut_slice(&mut self.entries[range])
+            }
+        }
+    )*}
+}
+impl_index!(
+    ops::Range<usize>,
+    ops::RangeFrom<usize>,
+    ops::RangeFull,
+    ops::RangeInclusive<usize>,
+    ops::RangeTo<usize>,
+    ops::RangeToInclusive<usize>,
+    (Bound<usize>, Bound<usize>)
+);
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn slice_index() {
+        fn check(
+            vec_slice: &[(i32, i32)],
+            map_slice: &Slice<i32, i32>,
+            sub_slice: &Slice<i32, i32>,
+        ) {
+            assert_eq!(map_slice as *const _, sub_slice as *const _);
+            itertools::assert_equal(
+                vec_slice.iter().copied(),
+                map_slice.iter().map(|(&k, &v)| (k, v)),
+            );
+            itertools::assert_equal(vec_slice.iter().map(|(k, _)| k), map_slice.keys());
+            itertools::assert_equal(vec_slice.iter().map(|(_, v)| v), map_slice.values());
+        }
+
+        let vec: Vec<(i32, i32)> = (0..10).map(|i| (i, i * i)).collect();
+        let map: IndexMap<i32, i32> = vec.iter().cloned().collect();
+        let slice = map.as_slice();
+
+        // RangeFull
+        check(&vec[..], &map[..], &slice[..]);
+
+        for i in 0usize..10 {
+            // Index
+            assert_eq!(vec[i].1, map[i]);
+            assert_eq!(vec[i].1, slice[i]);
+            assert_eq!(map[&(i as i32)], map[i]);
+            assert_eq!(map[&(i as i32)], slice[i]);
+
+            // RangeFrom
+            check(&vec[i..], &map[i..], &slice[i..]);
+
+            // RangeTo
+            check(&vec[..i], &map[..i], &slice[..i]);
+
+            // RangeToInclusive
+            check(&vec[..=i], &map[..=i], &slice[..=i]);
+
+            // (Bound<usize>, Bound<usize>)
+            let bounds = (Bound::Excluded(i), Bound::Unbounded);
+            check(&vec[i + 1..], &map[bounds], &slice[bounds]);
+
+            for j in i..=10 {
+                // Range
+                check(&vec[i..j], &map[i..j], &slice[i..j]);
+            }
+
+            for j in i..10 {
+                // RangeInclusive
+                check(&vec[i..=j], &map[i..=j], &slice[i..=j]);
+            }
+        }
+    }
+
+    #[test]
+    fn slice_index_mut() {
+        fn check_mut(
+            vec_slice: &[(i32, i32)],
+            map_slice: &mut Slice<i32, i32>,
+            sub_slice: &mut Slice<i32, i32>,
+        ) {
+            assert_eq!(map_slice, sub_slice);
+            itertools::assert_equal(
+                vec_slice.iter().copied(),
+                map_slice.iter_mut().map(|(&k, &mut v)| (k, v)),
+            );
+            itertools::assert_equal(
+                vec_slice.iter().map(|&(_, v)| v),
+                map_slice.values_mut().map(|&mut v| v),
+            );
+        }
+
+        let vec: Vec<(i32, i32)> = (0..10).map(|i| (i, i * i)).collect();
+        let mut map: IndexMap<i32, i32> = vec.iter().cloned().collect();
+        let mut map2 = map.clone();
+        let slice = map2.as_mut_slice();
+
+        // RangeFull
+        check_mut(&vec[..], &mut map[..], &mut slice[..]);
+
+        for i in 0usize..10 {
+            // IndexMut
+            assert_eq!(&mut map[i], &mut slice[i]);
+
+            // RangeFrom
+            check_mut(&vec[i..], &mut map[i..], &mut slice[i..]);
+
+            // RangeTo
+            check_mut(&vec[..i], &mut map[..i], &mut slice[..i]);
+
+            // RangeToInclusive
+            check_mut(&vec[..=i], &mut map[..=i], &mut slice[..=i]);
+
+            // (Bound<usize>, Bound<usize>)
+            let bounds = (Bound::Excluded(i), Bound::Unbounded);
+            check_mut(&vec[i + 1..], &mut map[bounds], &mut slice[bounds]);
+
+            for j in i..=10 {
+                // Range
+                check_mut(&vec[i..j], &mut map[i..j], &mut slice[i..j]);
+            }
+
+            for j in i..10 {
+                // RangeInclusive
+                check_mut(&vec[i..=j], &mut map[i..=j], &mut slice[i..=j]);
+            }
+        }
+    }
+}
diff --git a/third_party/rust/indexmap/src/map/tests.rs b/third_party/rust/indexmap/src/map/tests.rs
new file mode 100644
index 0000000000..bba78ff54c
--- /dev/null
+++ b/third_party/rust/indexmap/src/map/tests.rs
@@ -0,0 +1,727 @@
+use super::*;
+use std::string::String;
+
+#[test]
+fn it_works() {
+    let mut map = IndexMap::new();
+    assert_eq!(map.is_empty(), true);
+    map.insert(1, ());
+    map.insert(1, ());
+    assert_eq!(map.len(), 1);
+    assert!(map.get(&1).is_some());
+    assert_eq!(map.is_empty(), false);
+}
+
+#[test]
+fn new() {
+    let map = IndexMap::<String, String>::new();
+    println!("{:?}", map);
+    assert_eq!(map.capacity(), 0);
+    assert_eq!(map.len(), 0);
+    assert_eq!(map.is_empty(), true);
+}
+
+#[test]
+fn insert() {
+    let insert = [0, 4, 2, 12, 8, 7, 11, 5];
+    let not_present = [1, 3, 6, 9, 10];
+    let mut map = IndexMap::with_capacity(insert.len());
+
+    for (i, &elt) in insert.iter().enumerate() {
+        assert_eq!(map.len(), i);
+        map.insert(elt, elt);
+        assert_eq!(map.len(), i + 1);
+        assert_eq!(map.get(&elt), Some(&elt));
+        assert_eq!(map[&elt], elt);
+    }
+    println!("{:?}", map);
+
+    for &elt in &not_present {
+        assert!(map.get(&elt).is_none());
+    }
+}
+
+#[test]
+fn insert_full() {
+    let insert = vec![9, 2, 7, 1, 4, 6, 13];
+    let present = vec![1, 6, 2];
+    let mut map = IndexMap::with_capacity(insert.len());
+
+    for (i, &elt) in insert.iter().enumerate() {
+        assert_eq!(map.len(), i);
+        let (index, existing) = map.insert_full(elt, elt);
+        assert_eq!(existing, None);
+        assert_eq!(Some(index), map.get_full(&elt).map(|x| x.0));
+        assert_eq!(map.len(), i + 1);
+    }
+
+    let len = map.len();
+    for &elt in &present {
+        let (index, existing) = map.insert_full(elt, elt);
+        assert_eq!(existing, Some(elt));
+        assert_eq!(Some(index), map.get_full(&elt).map(|x| x.0));
+        assert_eq!(map.len(), len);
+    }
+}
+
+#[test]
+fn insert_2() {
+    let mut map = IndexMap::with_capacity(16);
+
+    let mut keys = vec![];
+    keys.extend(0..16);
+    keys.extend(if cfg!(miri) { 32..64 } else { 128..267 });
+
+    for &i in &keys {
+        let old_map = map.clone();
+        map.insert(i, ());
+        for key in old_map.keys() {
+            if map.get(key).is_none() {
+                println!("old_map: {:?}", old_map);
+                println!("map: {:?}", map);
+                panic!("did not find {} in map", key);
+            }
+        }
+    }
+
+    for &i in &keys {
+        assert!(map.get(&i).is_some(), "did not find {}", i);
+    }
+}
+
+#[test]
+fn insert_order() {
+    let insert = [0, 4, 2, 12, 8, 7, 11, 5, 3, 17, 19, 22, 23];
+    let mut map = IndexMap::new();
+
+    for &elt in &insert {
+        map.insert(elt, ());
+    }
+
+    assert_eq!(map.keys().count(), map.len());
+    assert_eq!(map.keys().count(), insert.len());
+    for (a, b) in insert.iter().zip(map.keys()) {
+        assert_eq!(a, b);
+    }
+    for (i, k) in (0..insert.len()).zip(map.keys()) {
+        assert_eq!(map.get_index(i).unwrap().0, k);
+    }
+}
+
+#[test]
+fn shift_insert() {
+    let insert = [0, 4, 2, 12, 8, 7, 11, 5, 3, 17, 19, 22, 23];
+    let mut map = IndexMap::new();
+
+    for &elt in &insert {
+        map.shift_insert(0, elt, ());
+    }
+
+    assert_eq!(map.keys().count(), map.len());
+    assert_eq!(map.keys().count(), insert.len());
+    for (a, b) in insert.iter().rev().zip(map.keys()) {
+        assert_eq!(a, b);
+    }
+    for (i, k) in (0..insert.len()).zip(map.keys()) {
+        assert_eq!(map.get_index(i).unwrap().0, k);
+    }
+
+    // "insert" that moves an existing entry
+    map.shift_insert(0, insert[0], ());
+    assert_eq!(map.keys().count(), insert.len());
+    assert_eq!(insert[0], map.keys()[0]);
+    for (a, b) in insert[1..].iter().rev().zip(map.keys().skip(1)) {
+        assert_eq!(a, b);
+    }
+}
+
+#[test]
+fn grow() {
+    let insert = [0, 4, 2, 12, 8, 7, 11];
+    let not_present = [1, 3, 6, 9, 10];
+    let mut map = IndexMap::with_capacity(insert.len());
+
+    for (i, &elt) in insert.iter().enumerate() {
+        assert_eq!(map.len(), i);
+        map.insert(elt, elt);
+        assert_eq!(map.len(), i + 1);
+        assert_eq!(map.get(&elt), Some(&elt));
+        assert_eq!(map[&elt], elt);
+    }
+
+    println!("{:?}", map);
+    for &elt in &insert {
+        map.insert(elt * 10, elt);
+    }
+    for &elt in &insert {
+        map.insert(elt * 100, elt);
+    }
+    for (i, &elt) in insert.iter().cycle().enumerate().take(100) {
+        map.insert(elt * 100 + i as i32, elt);
+    }
+    println!("{:?}", map);
+    for &elt in &not_present {
+        assert!(map.get(&elt).is_none());
+    }
+}
+
+#[test]
+fn reserve() {
+    let mut map = IndexMap::<usize, usize>::new();
+    assert_eq!(map.capacity(), 0);
+    map.reserve(100);
+    let capacity = map.capacity();
+    assert!(capacity >= 100);
+    for i in 0..capacity {
+        assert_eq!(map.len(), i);
+        map.insert(i, i * i);
+        assert_eq!(map.len(), i + 1);
+        assert_eq!(map.capacity(), capacity);
+        assert_eq!(map.get(&i), Some(&(i * i)));
+    }
+    map.insert(capacity, std::usize::MAX);
+    assert_eq!(map.len(), capacity + 1);
+    assert!(map.capacity() > capacity);
+    assert_eq!(map.get(&capacity), Some(&std::usize::MAX));
+}
+
+#[test]
+fn try_reserve() {
+    let mut map = IndexMap::<usize, usize>::new();
+    assert_eq!(map.capacity(), 0);
+    assert_eq!(map.try_reserve(100), Ok(()));
+    assert!(map.capacity() >= 100);
+    assert!(map.try_reserve(usize::MAX).is_err());
+}
+
+#[test]
+fn shrink_to_fit() {
+    let mut map = IndexMap::<usize, usize>::new();
+    assert_eq!(map.capacity(), 0);
+    for i in 0..100 {
+        assert_eq!(map.len(), i);
+        map.insert(i, i * i);
+        assert_eq!(map.len(), i + 1);
+        assert!(map.capacity() >= i + 1);
+        assert_eq!(map.get(&i), Some(&(i * i)));
+        map.shrink_to_fit();
+        assert_eq!(map.len(), i + 1);
+        assert_eq!(map.capacity(), i + 1);
+        assert_eq!(map.get(&i), Some(&(i * i)));
+    }
+}
+
+#[test]
+fn remove() {
+    let insert = [0, 4, 2, 12, 8, 7, 11, 5, 3, 17, 19, 22, 23];
+    let mut map = IndexMap::new();
+
+    for &elt in &insert {
+        map.insert(elt, elt);
+    }
+
+    assert_eq!(map.keys().count(), map.len());
+    assert_eq!(map.keys().count(), insert.len());
+    for (a, b) in insert.iter().zip(map.keys()) {
+        assert_eq!(a, b);
+    }
+
+    let remove_fail = [99, 77];
+    let remove = [4, 12, 8, 7];
+
+    for &key in &remove_fail {
+        assert!(map.swap_remove_full(&key).is_none());
+    }
+    println!("{:?}", map);
+    for &key in &remove {
+        //println!("{:?}", map);
+        let index = map.get_full(&key).unwrap().0;
+        assert_eq!(map.swap_remove_full(&key), Some((index, key, key)));
+    }
+    println!("{:?}", map);
+
+    for key in &insert {
+        assert_eq!(map.get(key).is_some(), !remove.contains(key));
+    }
+    assert_eq!(map.len(), insert.len() - remove.len());
+    assert_eq!(map.keys().count(), insert.len() - remove.len());
+}
+
+#[test]
+fn remove_to_empty() {
+    let mut map = indexmap! { 0 => 0, 4 => 4, 5 => 5 };
+    map.swap_remove(&5).unwrap();
+    map.swap_remove(&4).unwrap();
+    map.swap_remove(&0).unwrap();
+    assert!(map.is_empty());
+}
+
+#[test]
+fn swap_remove_index() {
+    let insert = [0, 4, 2, 12, 8, 7, 11, 5, 3, 17, 19, 22, 23];
+    let mut map = IndexMap::new();
+
+    for &elt in &insert {
+        map.insert(elt, elt * 2);
+    }
+
+    let mut vector = insert.to_vec();
+    let remove_sequence = &[3, 3, 10, 4, 5, 4, 3, 0, 1];
+
+    // check that the same swap remove sequence on vec and map
+    // have the same result.
+    for &rm in remove_sequence {
+        let out_vec = vector.swap_remove(rm);
+        let (out_map, _) = map.swap_remove_index(rm).unwrap();
+        assert_eq!(out_vec, out_map);
+    }
+    assert_eq!(vector.len(), map.len());
+    for (a, b) in vector.iter().zip(map.keys()) {
+        assert_eq!(a, b);
+    }
+}
+
+#[test]
+fn partial_eq_and_eq() {
+    let mut map_a = IndexMap::new();
+    map_a.insert(1, "1");
+    map_a.insert(2, "2");
+    let mut map_b = map_a.clone();
+    assert_eq!(map_a, map_b);
+    map_b.swap_remove(&1);
+    assert_ne!(map_a, map_b);
+
+    let map_c: IndexMap<_, String> = map_b.into_iter().map(|(k, v)| (k, v.into())).collect();
+    assert_ne!(map_a, map_c);
+    assert_ne!(map_c, map_a);
+}
+
+#[test]
+fn extend() {
+    let mut map = IndexMap::new();
+    map.extend(vec![(&1, &2), (&3, &4)]);
+    map.extend(vec![(5, 6)]);
+    assert_eq!(
+        map.into_iter().collect::<Vec<_>>(),
+        vec![(1, 2), (3, 4), (5, 6)]
+    );
+}
+
+#[test]
+fn entry() {
+    let mut map = IndexMap::new();
+
+    map.insert(1, "1");
+    map.insert(2, "2");
+    {
+        let e = map.entry(3);
+        assert_eq!(e.index(), 2);
+        let e = e.or_insert("3");
+        assert_eq!(e, &"3");
+    }
+
+    let e = map.entry(2);
+    assert_eq!(e.index(), 1);
+    assert_eq!(e.key(), &2);
+    match e {
+        Entry::Occupied(ref e) => assert_eq!(e.get(), &"2"),
+        Entry::Vacant(_) => panic!(),
+    }
+    assert_eq!(e.or_insert("4"), &"2");
+}
+
+#[test]
+fn entry_and_modify() {
+    let mut map = IndexMap::new();
+
+    map.insert(1, "1");
+    map.entry(1).and_modify(|x| *x = "2");
+    assert_eq!(Some(&"2"), map.get(&1));
+
+    map.entry(2).and_modify(|x| *x = "doesn't exist");
+    assert_eq!(None, map.get(&2));
+}
+
+#[test]
+fn entry_or_default() {
+    let mut map = IndexMap::new();
+
+    #[derive(Debug, PartialEq)]
+    enum TestEnum {
+        DefaultValue,
+        NonDefaultValue,
+    }
+
+    impl Default for TestEnum {
+        fn default() -> Self {
+            TestEnum::DefaultValue
+        }
+    }
+
+    map.insert(1, TestEnum::NonDefaultValue);
+    assert_eq!(&mut TestEnum::NonDefaultValue, map.entry(1).or_default());
+
+    assert_eq!(&mut TestEnum::DefaultValue, map.entry(2).or_default());
+}
+
+#[test]
+fn occupied_entry_key() {
+    // These keys match hash and equality, but their addresses are distinct.
+    let (k1, k2) = (&mut 1, &mut 1);
+    let k1_ptr = k1 as *const i32;
+    let k2_ptr = k2 as *const i32;
+    assert_ne!(k1_ptr, k2_ptr);
+
+    let mut map = IndexMap::new();
+    map.insert(k1, "value");
+    match map.entry(k2) {
+        Entry::Occupied(ref e) => {
+            // `OccupiedEntry::key` should reference the key in the map,
+            // not the key that was used to find the entry.
+            let ptr = *e.key() as *const i32;
+            assert_eq!(ptr, k1_ptr);
+            assert_ne!(ptr, k2_ptr);
+        }
+        Entry::Vacant(_) => panic!(),
+    }
+}
+
+#[test]
+fn get_index_entry() {
+    let mut map = IndexMap::new();
+
+    assert!(map.get_index_entry(0).is_none());
+
+    map.insert(0, "0");
+    map.insert(1, "1");
+    map.insert(2, "2");
+    map.insert(3, "3");
+
+    assert!(map.get_index_entry(4).is_none());
+
+    {
+        let e = map.get_index_entry(1).unwrap();
+        assert_eq!(*e.key(), 1);
+        assert_eq!(*e.get(), "1");
+        assert_eq!(e.swap_remove(), "1");
+    }
+
+    {
+        let mut e = map.get_index_entry(1).unwrap();
+        assert_eq!(*e.key(), 3);
+        assert_eq!(*e.get(), "3");
+        assert_eq!(e.insert("4"), "3");
+    }
+
+    assert_eq!(*map.get(&3).unwrap(), "4");
+}
+
+#[test]
+fn keys() {
+    let vec = vec![(1, 'a'), (2, 'b'), (3, 'c')];
+    let map: IndexMap<_, _> = vec.into_iter().collect();
+    let keys: Vec<_> = map.keys().copied().collect();
+    assert_eq!(keys.len(), 3);
+    assert!(keys.contains(&1));
+    assert!(keys.contains(&2));
+    assert!(keys.contains(&3));
+}
+
+#[test]
+fn into_keys() {
+    let vec = vec![(1, 'a'), (2, 'b'), (3, 'c')];
+    let map: IndexMap<_, _> = vec.into_iter().collect();
+    let keys: Vec<i32> = map.into_keys().collect();
+    assert_eq!(keys.len(), 3);
+    assert!(keys.contains(&1));
+    assert!(keys.contains(&2));
+    assert!(keys.contains(&3));
+}
+
+#[test]
+fn values() {
+    let vec = vec![(1, 'a'), (2, 'b'), (3, 'c')];
+    let map: IndexMap<_, _> = vec.into_iter().collect();
+    let values: Vec<_> = map.values().copied().collect();
+    assert_eq!(values.len(), 3);
+    assert!(values.contains(&'a'));
+    assert!(values.contains(&'b'));
+    assert!(values.contains(&'c'));
+}
+
+#[test]
+fn values_mut() {
+    let vec = vec![(1, 1), (2, 2), (3, 3)];
+    let mut map: IndexMap<_, _> = vec.into_iter().collect();
+    for value in map.values_mut() {
+        *value *= 2
+    }
+    let values: Vec<_> = map.values().copied().collect();
+    assert_eq!(values.len(), 3);
+    assert!(values.contains(&2));
+    assert!(values.contains(&4));
+    assert!(values.contains(&6));
+}
+
+#[test]
+fn into_values() {
+    let vec = vec![(1, 'a'), (2, 'b'), (3, 'c')];
+    let map: IndexMap<_, _> = vec.into_iter().collect();
+    let values: Vec<char> = map.into_values().collect();
+    assert_eq!(values.len(), 3);
+    assert!(values.contains(&'a'));
+    assert!(values.contains(&'b'));
+    assert!(values.contains(&'c'));
+}
+
+#[test]
+#[cfg(feature = "std")]
+fn from_array() {
+    let map = IndexMap::from([(1, 2), (3, 4)]);
+    let mut expected = IndexMap::new();
+    expected.insert(1, 2);
+    expected.insert(3, 4);
+
+    assert_eq!(map, expected)
+}
+
+#[test]
+fn iter_default() {
+    struct K;
+    struct V;
+    fn assert_default<T>()
+    where
+        T: Default + Iterator,
+    {
+        assert!(T::default().next().is_none());
+    }
+    assert_default::<Iter<'static, K, V>>();
+    assert_default::<IterMut<'static, K, V>>();
+    assert_default::<IntoIter<K, V>>();
+    assert_default::<Keys<'static, K, V>>();
+    assert_default::<IntoKeys<K, V>>();
+    assert_default::<Values<'static, K, V>>();
+    assert_default::<ValuesMut<'static, K, V>>();
+    assert_default::<IntoValues<K, V>>();
+}
+
+#[test]
+fn test_binary_search_by() {
+    // adapted from std's test for binary_search
+    let b: IndexMap<_, i32> = []
+        .into_iter()
+        .enumerate()
+        .map(|(i, x)| (i + 100, x))
+        .collect();
+    assert_eq!(b.binary_search_by(|_, x| x.cmp(&5)), Err(0));
+
+    let b: IndexMap<_, i32> = [4]
+        .into_iter()
+        .enumerate()
+        .map(|(i, x)| (i + 100, x))
+        .collect();
+    assert_eq!(b.binary_search_by(|_, x| x.cmp(&3)), Err(0));
+    assert_eq!(b.binary_search_by(|_, x| x.cmp(&4)), Ok(0));
+    assert_eq!(b.binary_search_by(|_, x| x.cmp(&5)), Err(1));
+
+    let b: IndexMap<_, i32> = [1, 2, 4, 6, 8, 9]
+        .into_iter()
+        .enumerate()
+        .map(|(i, x)| (i + 100, x))
+        .collect();
+    assert_eq!(b.binary_search_by(|_, x| x.cmp(&5)), Err(3));
+    assert_eq!(b.binary_search_by(|_, x| x.cmp(&6)), Ok(3));
+    assert_eq!(b.binary_search_by(|_, x| x.cmp(&7)), Err(4));
+    assert_eq!(b.binary_search_by(|_, x| x.cmp(&8)), Ok(4));
+
+    let b: IndexMap<_, i32> = [1, 2, 4, 5, 6, 8]
+        .into_iter()
+        .enumerate()
+        .map(|(i, x)| (i + 100, x))
+        .collect();
+    assert_eq!(b.binary_search_by(|_, x| x.cmp(&9)), Err(6));
+
+    let b: IndexMap<_, i32> = [1, 2, 4, 6, 7, 8, 9]
+        .into_iter()
+        .enumerate()
+        .map(|(i, x)| (i + 100, x))
+        .collect();
+    assert_eq!(b.binary_search_by(|_, x| x.cmp(&6)), Ok(3));
+    assert_eq!(b.binary_search_by(|_, x| x.cmp(&5)), Err(3));
+    assert_eq!(b.binary_search_by(|_, x| x.cmp(&8)), Ok(5));
+
+    let b: IndexMap<_, i32> = [1, 2, 4, 5, 6, 8, 9]
+        .into_iter()
+        .enumerate()
+        .map(|(i, x)| (i + 100, x))
+        .collect();
+    assert_eq!(b.binary_search_by(|_, x| x.cmp(&7)), Err(5));
+    assert_eq!(b.binary_search_by(|_, x| x.cmp(&0)), Err(0));
+
+    let b: IndexMap<_, i32> = [1, 3, 3, 3, 7]
+        .into_iter()
+        .enumerate()
+        .map(|(i, x)| (i + 100, x))
+        .collect();
+    assert_eq!(b.binary_search_by(|_, x| x.cmp(&0)), Err(0));
+    assert_eq!(b.binary_search_by(|_, x| x.cmp(&1)), Ok(0));
+    assert_eq!(b.binary_search_by(|_, x| x.cmp(&2)), Err(1));
+    assert!(match b.binary_search_by(|_, x| x.cmp(&3)) {
+        Ok(1..=3) => true,
+        _ => false,
+    });
+    assert!(match b.binary_search_by(|_, x| x.cmp(&3)) {
+        Ok(1..=3) => true,
+        _ => false,
+    });
+    assert_eq!(b.binary_search_by(|_, x| x.cmp(&4)), Err(4));
+    assert_eq!(b.binary_search_by(|_, x| x.cmp(&5)), Err(4));
+    assert_eq!(b.binary_search_by(|_, x| x.cmp(&6)), Err(4));
+    assert_eq!(b.binary_search_by(|_, x| x.cmp(&7)), Ok(4));
+    assert_eq!(b.binary_search_by(|_, x| x.cmp(&8)), Err(5));
+}
+
+#[test]
+fn test_binary_search_by_key() {
+    // adapted from std's test for binary_search
+    let b: IndexMap<_, i32> = []
+        .into_iter()
+        .enumerate()
+        .map(|(i, x)| (i + 100, x))
+        .collect();
+    assert_eq!(b.binary_search_by_key(&5, |_, &x| x), Err(0));
+
+    let b: IndexMap<_, i32> = [4]
+        .into_iter()
+        .enumerate()
+        .map(|(i, x)| (i + 100, x))
+        .collect();
+    assert_eq!(b.binary_search_by_key(&3, |_, &x| x), Err(0));
+    assert_eq!(b.binary_search_by_key(&4, |_, &x| x), Ok(0));
+    assert_eq!(b.binary_search_by_key(&5, |_, &x| x), Err(1));
+
+    let b: IndexMap<_, i32> = [1, 2, 4, 6, 8, 9]
+        .into_iter()
+        .enumerate()
+        .map(|(i, x)| (i + 100, x))
+        .collect();
+    assert_eq!(b.binary_search_by_key(&5, |_, &x| x), Err(3));
+    assert_eq!(b.binary_search_by_key(&6, |_, &x| x), Ok(3));
+    assert_eq!(b.binary_search_by_key(&7, |_, &x| x), Err(4));
+    assert_eq!(b.binary_search_by_key(&8, |_, &x| x), Ok(4));
+
+    let b: IndexMap<_, i32> = [1, 2, 4, 5, 6, 8]
+        .into_iter()
+        .enumerate()
+        .map(|(i, x)| (i + 100, x))
+        .collect();
+    assert_eq!(b.binary_search_by_key(&9, |_, &x| x), Err(6));
+
+    let b: IndexMap<_, i32> = [1, 2, 4, 6, 7, 8, 9]
+        .into_iter()
+        .enumerate()
+        .map(|(i, x)| (i + 100, x))
+        .collect();
+    assert_eq!(b.binary_search_by_key(&6, |_, &x| x), Ok(3));
+    assert_eq!(b.binary_search_by_key(&5, |_, &x| x), Err(3));
+    assert_eq!(b.binary_search_by_key(&8, |_, &x| x), Ok(5));
+
+    let b: IndexMap<_, i32> = [1, 2, 4, 5, 6, 8, 9]
+        .into_iter()
+        .enumerate()
+        .map(|(i, x)| (i + 100, x))
+        .collect();
+    assert_eq!(b.binary_search_by_key(&7, |_, &x| x), Err(5));
+    assert_eq!(b.binary_search_by_key(&0, |_, &x| x), Err(0));
+
+    let b: IndexMap<_, i32> = [1, 3, 3, 3, 7]
+        .into_iter()
+        .enumerate()
+        .map(|(i, x)| (i + 100, x))
+        .collect();
+    assert_eq!(b.binary_search_by_key(&0, |_, &x| x), Err(0));
+    assert_eq!(b.binary_search_by_key(&1, |_, &x| x), Ok(0));
+    assert_eq!(b.binary_search_by_key(&2, |_, &x| x), Err(1));
+    assert!(match b.binary_search_by_key(&3, |_, &x| x) {
+        Ok(1..=3) => true,
+        _ => false,
+    });
+    assert!(match b.binary_search_by_key(&3, |_, &x| x) {
+        Ok(1..=3) => true,
+        _ => false,
+    });
+    assert_eq!(b.binary_search_by_key(&4, |_, &x| x), Err(4));
+    assert_eq!(b.binary_search_by_key(&5, |_, &x| x), Err(4));
+    assert_eq!(b.binary_search_by_key(&6, |_, &x| x), Err(4));
+    assert_eq!(b.binary_search_by_key(&7, |_, &x| x), Ok(4));
+    assert_eq!(b.binary_search_by_key(&8, |_, &x| x), Err(5));
+}
+
+#[test]
+fn test_partition_point() {
+    // adapted from std's test for partition_point
+    let b: IndexMap<_, i32> = []
+        .into_iter()
+        .enumerate()
+        .map(|(i, x)| (i + 100, x))
+        .collect();
+    assert_eq!(b.partition_point(|_, &x| x < 5), 0);
+
+    let b: IndexMap<_, i32> = [4]
+        .into_iter()
+        .enumerate()
+        .map(|(i, x)| (i + 100, x))
+        .collect();
+    assert_eq!(b.partition_point(|_, &x| x < 3), 0);
+    assert_eq!(b.partition_point(|_, &x| x < 4), 0);
+    assert_eq!(b.partition_point(|_, &x| x < 5), 1);
+
+    let b: IndexMap<_, i32> = [1, 2, 4, 6, 8, 9]
+        .into_iter()
+        .enumerate()
+        .map(|(i, x)| (i + 100, x))
+        .collect();
+    assert_eq!(b.partition_point(|_, &x| x < 5), 3);
+    assert_eq!(b.partition_point(|_, &x| x < 6), 3);
+    assert_eq!(b.partition_point(|_, &x| x < 7), 4);
+    assert_eq!(b.partition_point(|_, &x| x < 8), 4);
+
+    let b: IndexMap<_, i32> = [1, 2, 4, 5, 6, 8]
+        .into_iter()
+        .enumerate()
+        .map(|(i, x)| (i + 100, x))
+        .collect();
+    assert_eq!(b.partition_point(|_, &x| x < 9), 6);
+
+    let b: IndexMap<_, i32> = [1, 2, 4, 6, 7, 8, 9]
+        .into_iter()
+        .enumerate()
+        .map(|(i, x)| (i + 100, x))
+        .collect();
+    assert_eq!(b.partition_point(|_, &x| x < 6), 3);
+    assert_eq!(b.partition_point(|_, &x| x < 5), 3);
+    assert_eq!(b.partition_point(|_, &x| x < 8), 5);
+
+    let b: IndexMap<_, i32> = [1, 2, 4, 5, 6, 8, 9]
+        .into_iter()
+        .enumerate()
+        .map(|(i, x)| (i + 100, x))
+        .collect();
+    assert_eq!(b.partition_point(|_, &x| x < 7), 5);
+    assert_eq!(b.partition_point(|_, &x| x < 0), 0);
+
+    let b: IndexMap<_, i32> = [1, 3, 3, 3, 7]
+        .into_iter()
+        .enumerate()
+        .map(|(i, x)| (i + 100, x))
+        .collect();
+    assert_eq!(b.partition_point(|_, &x| x < 0), 0);
+    assert_eq!(b.partition_point(|_, &x| x < 1), 0);
+    assert_eq!(b.partition_point(|_, &x| x < 2), 1);
+    assert_eq!(b.partition_point(|_, &x| x < 3), 1);
+    assert_eq!(b.partition_point(|_, &x| x < 4), 4);
+    assert_eq!(b.partition_point(|_, &x| x < 5), 4);
+    assert_eq!(b.partition_point(|_, &x| x < 6), 4);
+    assert_eq!(b.partition_point(|_, &x| x < 7), 4);
+    assert_eq!(b.partition_point(|_, &x| x < 8), 5);
+}
diff --git a/third_party/rust/indexmap/src/mutable_keys.rs b/third_party/rust/indexmap/src/mutable_keys.rs
deleted file mode 100644
index 35a90c4723..0000000000
--- a/third_party/rust/indexmap/src/mutable_keys.rs
+++ /dev/null
@@ -1,75 +0,0 @@
-use core::hash::{BuildHasher, Hash};
-
-use super::{Equivalent, IndexMap};
-
-pub struct PrivateMarker {}
-
-/// Opt-in mutable access to keys.
-///
-/// These methods expose `&mut K`, mutable references to the key as it is stored
-/// in the map.
-/// You are allowed to modify the keys in the hashmap **if the modification
-/// does not change the key’s hash and equality**.
-///
-/// If keys are modified erroneously, you can no longer look them up.
-/// This is sound (memory safe) but a logical error hazard (just like
-/// implementing PartialEq, Eq, or Hash incorrectly would be).
-///
-/// `use` this trait to enable its methods for `IndexMap`.
-pub trait MutableKeys {
-    type Key;
-    type Value;
-
-    /// Return item index, mutable reference to key and value
-    fn get_full_mut2<Q: ?Sized>(
-        &mut self,
-        key: &Q,
-    ) -> Option<(usize, &mut Self::Key, &mut Self::Value)>
-    where
-        Q: Hash + Equivalent<Self::Key>;
-
-    /// Scan through each key-value pair in the map and keep those where the
-    /// closure `keep` returns `true`.
-    ///
-    /// The elements are visited in order, and remaining elements keep their
-    /// order.
-    ///
-    /// Computes in **O(n)** time (average).
-    fn retain2<F>(&mut self, keep: F)
-    where
-        F: FnMut(&mut Self::Key, &mut Self::Value) -> bool;
-
-    /// This method is not useful in itself – it is there to “seal” the trait
-    /// for external implementation, so that we can add methods without
-    /// causing breaking changes.
-    fn __private_marker(&self) -> PrivateMarker;
-}
-
-/// Opt-in mutable access to keys.
-///
-/// See [`MutableKeys`](trait.MutableKeys.html) for more information.
-impl<K, V, S> MutableKeys for IndexMap<K, V, S>
-where
-    K: Eq + Hash,
-    S: BuildHasher,
-{
-    type Key = K;
-    type Value = V;
-    fn get_full_mut2<Q: ?Sized>(&mut self, key: &Q) -> Option<(usize, &mut K, &mut V)>
-    where
-        Q: Hash + Equivalent<K>,
-    {
-        self.get_full_mut2_impl(key)
-    }
-
-    fn retain2<F>(&mut self, keep: F)
-    where
-        F: FnMut(&mut K, &mut V) -> bool,
-    {
-        self.retain_mut(keep)
-    }
-
-    fn __private_marker(&self) -> PrivateMarker {
-        PrivateMarker {}
-    }
-}
diff --git a/third_party/rust/indexmap/src/rayon/map.rs b/third_party/rust/indexmap/src/rayon/map.rs
index 8819f13ed7..8236cf70f0 100644
--- a/third_party/rust/indexmap/src/rayon/map.rs
+++ b/third_party/rust/indexmap/src/rayon/map.rs
@@ -1,25 +1,24 @@
-//! Parallel iterator types for `IndexMap` with [rayon](https://docs.rs/rayon/1.0/rayon).
+//! Parallel iterator types for [`IndexMap`] with [`rayon`][::rayon].
 //!
 //! You will rarely need to interact with this module directly unless you need to name one of the
 //! iterator types.
-//!
-//! Requires crate feature `"rayon"`
 
 use super::collect;
 use rayon::iter::plumbing::{Consumer, ProducerCallback, UnindexedConsumer};
 use rayon::prelude::*;
 
 use crate::vec::Vec;
+use alloc::boxed::Box;
 use core::cmp::Ordering;
 use core::fmt;
 use core::hash::{BuildHasher, Hash};
 use core::ops::RangeBounds;
 
+use crate::map::Slice;
 use crate::Bucket;
 use crate::Entries;
 use crate::IndexMap;
 
-/// Requires crate feature `"rayon"`.
 impl<K, V, S> IntoParallelIterator for IndexMap<K, V, S>
 where
     K: Send,
@@ -35,13 +34,25 @@ where
     }
 }
 
-/// A parallel owning iterator over the entries of a `IndexMap`.
-///
-/// This `struct` is created by the [`into_par_iter`] method on [`IndexMap`]
-/// (provided by rayon's `IntoParallelIterator` trait). See its documentation for more.
+impl<K, V> IntoParallelIterator for Box<Slice<K, V>>
+where
+    K: Send,
+    V: Send,
+{
+    type Item = (K, V);
+    type Iter = IntoParIter<K, V>;
+
+    fn into_par_iter(self) -> Self::Iter {
+        IntoParIter {
+            entries: self.into_entries(),
+        }
+    }
+}
+
+/// A parallel owning iterator over the entries of an [`IndexMap`].
 ///
-/// [`into_par_iter`]: ../struct.IndexMap.html#method.into_par_iter
-/// [`IndexMap`]: ../struct.IndexMap.html
+/// This `struct` is created by the [`IndexMap::into_par_iter`] method
+/// (provided by rayon's [`IntoParallelIterator`] trait). See its documentation for more.
 pub struct IntoParIter<K, V> {
     entries: Vec<Bucket<K, V>>,
 }
@@ -63,7 +74,6 @@ impl<K: Send, V: Send> IndexedParallelIterator for IntoParIter<K, V> {
     indexed_parallel_iterator_methods!(Bucket::key_value);
 }
 
-/// Requires crate feature `"rayon"`.
 impl<'a, K, V, S> IntoParallelIterator for &'a IndexMap<K, V, S>
 where
     K: Sync,
@@ -79,13 +89,27 @@ where
     }
 }
 
-/// A parallel iterator over the entries of a `IndexMap`.
+impl<'a, K, V> IntoParallelIterator for &'a Slice<K, V>
+where
+    K: Sync,
+    V: Sync,
+{
+    type Item = (&'a K, &'a V);
+    type Iter = ParIter<'a, K, V>;
+
+    fn into_par_iter(self) -> Self::Iter {
+        ParIter {
+            entries: &self.entries,
+        }
+    }
+}
+
+/// A parallel iterator over the entries of an [`IndexMap`].
 ///
-/// This `struct` is created by the [`par_iter`] method on [`IndexMap`]
-/// (provided by rayon's `IntoParallelRefIterator` trait). See its documentation for more.
+/// This `struct` is created by the [`IndexMap::par_iter`] method
+/// (provided by rayon's [`IntoParallelRefIterator`] trait). See its documentation for more.
 ///
-/// [`par_iter`]: ../struct.IndexMap.html#method.par_iter
-/// [`IndexMap`]: ../struct.IndexMap.html
+/// [`IndexMap::par_iter`]: ../struct.IndexMap.html#method.par_iter
 pub struct ParIter<'a, K, V> {
     entries: &'a [Bucket<K, V>],
 }
@@ -113,7 +137,6 @@ impl<K: Sync, V: Sync> IndexedParallelIterator for ParIter<'_, K, V> {
     indexed_parallel_iterator_methods!(Bucket::refs);
 }
 
-/// Requires crate feature `"rayon"`.
 impl<'a, K, V, S> IntoParallelIterator for &'a mut IndexMap<K, V, S>
 where
     K: Sync + Send,
@@ -129,13 +152,27 @@ where
     }
 }
 
-/// A parallel mutable iterator over the entries of a `IndexMap`.
+impl<'a, K, V> IntoParallelIterator for &'a mut Slice<K, V>
+where
+    K: Sync + Send,
+    V: Send,
+{
+    type Item = (&'a K, &'a mut V);
+    type Iter = ParIterMut<'a, K, V>;
+
+    fn into_par_iter(self) -> Self::Iter {
+        ParIterMut {
+            entries: &mut self.entries,
+        }
+    }
+}
+
+/// A parallel mutable iterator over the entries of an [`IndexMap`].
 ///
-/// This `struct` is created by the [`par_iter_mut`] method on [`IndexMap`]
-/// (provided by rayon's `IntoParallelRefMutIterator` trait). See its documentation for more.
+/// This `struct` is created by the [`IndexMap::par_iter_mut`] method
+/// (provided by rayon's [`IntoParallelRefMutIterator`] trait). See its documentation for more.
 ///
-/// [`par_iter_mut`]: ../struct.IndexMap.html#method.par_iter_mut
-/// [`IndexMap`]: ../struct.IndexMap.html
+/// [`IndexMap::par_iter_mut`]: ../struct.IndexMap.html#method.par_iter_mut
 pub struct ParIterMut<'a, K, V> {
     entries: &'a mut [Bucket<K, V>],
 }
@@ -157,7 +194,6 @@ impl<K: Sync + Send, V: Send> IndexedParallelIterator for ParIterMut<'_, K, V> {
     indexed_parallel_iterator_methods!(Bucket::ref_mut);
 }
 
-/// Requires crate feature `"rayon"`.
 impl<'a, K, V, S> ParallelDrainRange<usize> for &'a mut IndexMap<K, V, S>
 where
     K: Send,
@@ -173,13 +209,12 @@ where
     }
 }
 
-/// A parallel draining iterator over the entries of a `IndexMap`.
+/// A parallel draining iterator over the entries of an [`IndexMap`].
 ///
-/// This `struct` is created by the [`par_drain`] method on [`IndexMap`]
-/// (provided by rayon's `ParallelDrainRange` trait). See its documentation for more.
+/// This `struct` is created by the [`IndexMap::par_drain`] method
+/// (provided by rayon's [`ParallelDrainRange`] trait). See its documentation for more.
 ///
-/// [`par_drain`]: ../struct.IndexMap.html#method.par_drain
-/// [`IndexMap`]: ../struct.IndexMap.html
+/// [`IndexMap::par_drain`]: ../struct.IndexMap.html#method.par_drain
 pub struct ParDrain<'a, K: Send, V: Send> {
     entries: rayon::vec::Drain<'a, Bucket<K, V>>,
 }
@@ -225,6 +260,37 @@ where
     }
 }
 
+/// Parallel iterator methods and other parallel methods.
+///
+/// The following methods **require crate feature `"rayon"`**.
+///
+/// See also the `IntoParallelIterator` implementations.
+impl<K, V> Slice<K, V>
+where
+    K: Sync,
+    V: Sync,
+{
+    /// Return a parallel iterator over the keys of the map slice.
+    ///
+    /// While parallel iterators can process items in any order, their relative order
+    /// in the slice is still preserved for operations like `reduce` and `collect`.
+    pub fn par_keys(&self) -> ParKeys<'_, K, V> {
+        ParKeys {
+            entries: &self.entries,
+        }
+    }
+
+    /// Return a parallel iterator over the values of the map slice.
+    ///
+    /// While parallel iterators can process items in any order, their relative order
+    /// in the slice is still preserved for operations like `reduce` and `collect`.
+    pub fn par_values(&self) -> ParValues<'_, K, V> {
+        ParValues {
+            entries: &self.entries,
+        }
+    }
+}
+
 impl<K, V, S> IndexMap<K, V, S>
 where
     K: Hash + Eq + Sync,
@@ -246,13 +312,10 @@ where
     }
 }
 
-/// A parallel iterator over the keys of a `IndexMap`.
+/// A parallel iterator over the keys of an [`IndexMap`].
 ///
-/// This `struct` is created by the [`par_keys`] method on [`IndexMap`]. See its
-/// documentation for more.
-///
-/// [`par_keys`]: ../struct.IndexMap.html#method.par_keys
-/// [`IndexMap`]: ../struct.IndexMap.html
+/// This `struct` is created by the [`IndexMap::par_keys`] method.
+/// See its documentation for more.
 pub struct ParKeys<'a, K, V> {
     entries: &'a [Bucket<K, V>],
 }
@@ -280,13 +343,10 @@ impl<K: Sync, V: Sync> IndexedParallelIterator for ParKeys<'_, K, V> {
     indexed_parallel_iterator_methods!(Bucket::key_ref);
 }
 
-/// A parallel iterator over the values of a `IndexMap`.
-///
-/// This `struct` is created by the [`par_values`] method on [`IndexMap`]. See its
-/// documentation for more.
+/// A parallel iterator over the values of an [`IndexMap`].
 ///
-/// [`par_values`]: ../struct.IndexMap.html#method.par_values
-/// [`IndexMap`]: ../struct.IndexMap.html
+/// This `struct` is created by the [`IndexMap::par_values`] method.
+/// See its documentation for more.
 pub struct ParValues<'a, K, V> {
     entries: &'a [Bucket<K, V>],
 }
@@ -314,7 +374,6 @@ impl<K: Sync, V: Sync> IndexedParallelIterator for ParValues<'_, K, V> {
     indexed_parallel_iterator_methods!(Bucket::value_ref);
 }
 
-/// Requires crate feature `"rayon"`.
 impl<K, V, S> IndexMap<K, V, S>
 where
     K: Send,
@@ -331,11 +390,26 @@ where
     }
 }
 
+impl<K, V> Slice<K, V>
+where
+    K: Send,
+    V: Send,
+{
+    /// Return a parallel iterator over mutable references to the the values of the map slice.
+    ///
+    /// While parallel iterators can process items in any order, their relative order
+    /// in the slice is still preserved for operations like `reduce` and `collect`.
+    pub fn par_values_mut(&mut self) -> ParValuesMut<'_, K, V> {
+        ParValuesMut {
+            entries: &mut self.entries,
+        }
+    }
+}
+
 impl<K, V, S> IndexMap<K, V, S>
 where
-    K: Hash + Eq + Send,
+    K: Send,
     V: Send,
-    S: BuildHasher,
 {
     /// Sort the map’s key-value pairs in parallel, by the default ordering of the keys.
     pub fn par_sort_keys(&mut self)
@@ -406,15 +480,24 @@ where
         entries.par_sort_unstable_by(move |a, b| cmp(&a.key, &a.value, &b.key, &b.value));
         IntoParIter { entries }
     }
+
+    /// Sort the map’s key-value pairs in place and in parallel, using a sort-key extraction
+    /// function.
+    pub fn par_sort_by_cached_key<T, F>(&mut self, sort_key: F)
+    where
+        T: Ord + Send,
+        F: Fn(&K, &V) -> T + Sync,
+    {
+        self.with_entries(move |entries| {
+            entries.par_sort_by_cached_key(move |a| sort_key(&a.key, &a.value));
+        });
+    }
 }
 
-/// A parallel mutable iterator over the values of a `IndexMap`.
-///
-/// This `struct` is created by the [`par_values_mut`] method on [`IndexMap`]. See its
-/// documentation for more.
+/// A parallel mutable iterator over the values of an [`IndexMap`].
 ///
-/// [`par_values_mut`]: ../struct.IndexMap.html#method.par_values_mut
-/// [`IndexMap`]: ../struct.IndexMap.html
+/// This `struct` is created by the [`IndexMap::par_values_mut`] method.
+/// See its documentation for more.
 pub struct ParValuesMut<'a, K, V> {
     entries: &'a mut [Bucket<K, V>],
 }
@@ -436,7 +519,6 @@ impl<K: Send, V: Send> IndexedParallelIterator for ParValuesMut<'_, K, V> {
     indexed_parallel_iterator_methods!(Bucket::value_mut);
 }
 
-/// Requires crate feature `"rayon"`.
 impl<K, V, S> FromParallelIterator<(K, V)> for IndexMap<K, V, S>
 where
     K: Eq + Hash + Send,
@@ -457,7 +539,6 @@ where
     }
 }
 
-/// Requires crate feature `"rayon"`.
 impl<K, V, S> ParallelExtend<(K, V)> for IndexMap<K, V, S>
 where
     K: Eq + Hash + Send,
@@ -474,7 +555,6 @@ where
     }
 }
 
-/// Requires crate feature `"rayon"`.
 impl<'a, K: 'a, V: 'a, S> ParallelExtend<(&'a K, &'a V)> for IndexMap<K, V, S>
 where
     K: Copy + Eq + Hash + Send + Sync,
diff --git a/third_party/rust/indexmap/src/rayon/mod.rs b/third_party/rust/indexmap/src/rayon/mod.rs
index ebb1ac2d1e..1d21569c18 100644
--- a/third_party/rust/indexmap/src/rayon/mod.rs
+++ b/third_party/rust/indexmap/src/rayon/mod.rs
@@ -1,3 +1,5 @@
+#![cfg_attr(docsrs, doc(cfg(feature = "rayon")))]
+
 use rayon::prelude::*;
 
 use alloc::collections::LinkedList;
diff --git a/third_party/rust/indexmap/src/rayon/set.rs b/third_party/rust/indexmap/src/rayon/set.rs
index 6749dc0d7f..3904234b20 100644
--- a/third_party/rust/indexmap/src/rayon/set.rs
+++ b/third_party/rust/indexmap/src/rayon/set.rs
@@ -1,26 +1,25 @@
-//! Parallel iterator types for `IndexSet` with [rayon](https://docs.rs/rayon/1.0/rayon).
+//! Parallel iterator types for [`IndexSet`] with [rayon][::rayon].
 //!
 //! You will rarely need to interact with this module directly unless you need to name one of the
 //! iterator types.
-//!
-//! Requires crate feature `"rayon"`.
 
 use super::collect;
 use rayon::iter::plumbing::{Consumer, ProducerCallback, UnindexedConsumer};
 use rayon::prelude::*;
 
 use crate::vec::Vec;
+use alloc::boxed::Box;
 use core::cmp::Ordering;
 use core::fmt;
 use core::hash::{BuildHasher, Hash};
 use core::ops::RangeBounds;
 
+use crate::set::Slice;
 use crate::Entries;
 use crate::IndexSet;
 
 type Bucket<T> = crate::Bucket<T, ()>;
 
-/// Requires crate feature `"rayon"`.
 impl<T, S> IntoParallelIterator for IndexSet<T, S>
 where
     T: Send,
@@ -35,13 +34,24 @@ where
     }
 }
 
-/// A parallel owning iterator over the items of a `IndexSet`.
-///
-/// This `struct` is created by the [`into_par_iter`] method on [`IndexSet`]
-/// (provided by rayon's `IntoParallelIterator` trait). See its documentation for more.
+impl<T> IntoParallelIterator for Box<Slice<T>>
+where
+    T: Send,
+{
+    type Item = T;
+    type Iter = IntoParIter<T>;
+
+    fn into_par_iter(self) -> Self::Iter {
+        IntoParIter {
+            entries: self.into_entries(),
+        }
+    }
+}
+
+/// A parallel owning iterator over the items of an [`IndexSet`].
 ///
-/// [`IndexSet`]: ../struct.IndexSet.html
-/// [`into_par_iter`]: ../struct.IndexSet.html#method.into_par_iter
+/// This `struct` is created by the [`IndexSet::into_par_iter`] method
+/// (provided by rayon's [`IntoParallelIterator`] trait). See its documentation for more.
 pub struct IntoParIter<T> {
     entries: Vec<Bucket<T>>,
 }
@@ -63,7 +73,6 @@ impl<T: Send> IndexedParallelIterator for IntoParIter<T> {
     indexed_parallel_iterator_methods!(Bucket::key);
 }
 
-/// Requires crate feature `"rayon"`.
 impl<'a, T, S> IntoParallelIterator for &'a IndexSet<T, S>
 where
     T: Sync,
@@ -78,13 +87,26 @@ where
     }
 }
 
-/// A parallel iterator over the items of a `IndexSet`.
+impl<'a, T> IntoParallelIterator for &'a Slice<T>
+where
+    T: Sync,
+{
+    type Item = &'a T;
+    type Iter = ParIter<'a, T>;
+
+    fn into_par_iter(self) -> Self::Iter {
+        ParIter {
+            entries: &self.entries,
+        }
+    }
+}
+
+/// A parallel iterator over the items of an [`IndexSet`].
 ///
-/// This `struct` is created by the [`par_iter`] method on [`IndexSet`]
-/// (provided by rayon's `IntoParallelRefIterator` trait). See its documentation for more.
+/// This `struct` is created by the [`IndexSet::par_iter`] method
+/// (provided by rayon's [`IntoParallelRefIterator`] trait). See its documentation for more.
 ///
-/// [`IndexSet`]: ../struct.IndexSet.html
-/// [`par_iter`]: ../struct.IndexSet.html#method.par_iter
+/// [`IndexSet::par_iter`]: ../struct.IndexSet.html#method.par_iter
 pub struct ParIter<'a, T> {
     entries: &'a [Bucket<T>],
 }
@@ -112,7 +134,6 @@ impl<T: Sync> IndexedParallelIterator for ParIter<'_, T> {
     indexed_parallel_iterator_methods!(Bucket::key_ref);
 }
 
-/// Requires crate feature `"rayon"`.
 impl<'a, T, S> ParallelDrainRange<usize> for &'a mut IndexSet<T, S>
 where
     T: Send,
@@ -127,13 +148,12 @@ where
     }
 }
 
-/// A parallel draining iterator over the items of a `IndexSet`.
+/// A parallel draining iterator over the items of an [`IndexSet`].
 ///
-/// This `struct` is created by the [`par_drain`] method on [`IndexSet`]
-/// (provided by rayon's `ParallelDrainRange` trait). See its documentation for more.
+/// This `struct` is created by the [`IndexSet::par_drain`] method
+/// (provided by rayon's [`ParallelDrainRange`] trait). See its documentation for more.
 ///
-/// [`par_drain`]: ../struct.IndexSet.html#method.par_drain
-/// [`IndexSet`]: ../struct.IndexSet.html
+/// [`IndexSet::par_drain`]: ../struct.IndexSet.html#method.par_drain
 pub struct ParDrain<'a, T: Send> {
     entries: rayon::vec::Drain<'a, Bucket<T>>,
 }
@@ -269,13 +289,10 @@ where
     }
 }
 
-/// A parallel iterator producing elements in the difference of `IndexSet`s.
+/// A parallel iterator producing elements in the difference of [`IndexSet`]s.
 ///
-/// This `struct` is created by the [`par_difference`] method on [`IndexSet`].
+/// This `struct` is created by the [`IndexSet::par_difference`] method.
 /// See its documentation for more.
-///
-/// [`IndexSet`]: ../struct.IndexSet.html
-/// [`par_difference`]: ../struct.IndexSet.html#method.par_difference
 pub struct ParDifference<'a, T, S1, S2> {
     set1: &'a IndexSet<T, S1>,
     set2: &'a IndexSet<T, S2>,
@@ -320,13 +337,10 @@ where
     }
 }
 
-/// A parallel iterator producing elements in the intersection of `IndexSet`s.
+/// A parallel iterator producing elements in the intersection of [`IndexSet`]s.
 ///
-/// This `struct` is created by the [`par_intersection`] method on [`IndexSet`].
+/// This `struct` is created by the [`IndexSet::par_intersection`] method.
 /// See its documentation for more.
-///
-/// [`IndexSet`]: ../struct.IndexSet.html
-/// [`par_intersection`]: ../struct.IndexSet.html#method.par_intersection
 pub struct ParIntersection<'a, T, S1, S2> {
     set1: &'a IndexSet<T, S1>,
     set2: &'a IndexSet<T, S2>,
@@ -371,13 +385,10 @@ where
     }
 }
 
-/// A parallel iterator producing elements in the symmetric difference of `IndexSet`s.
-///
-/// This `struct` is created by the [`par_symmetric_difference`] method on
-/// [`IndexSet`]. See its documentation for more.
+/// A parallel iterator producing elements in the symmetric difference of [`IndexSet`]s.
 ///
-/// [`IndexSet`]: ../struct.IndexSet.html
-/// [`par_symmetric_difference`]: ../struct.IndexSet.html#method.par_symmetric_difference
+/// This `struct` is created by the [`IndexSet::par_symmetric_difference`] method.
+/// See its documentation for more.
 pub struct ParSymmetricDifference<'a, T, S1, S2> {
     set1: &'a IndexSet<T, S1>,
     set2: &'a IndexSet<T, S2>,
@@ -422,13 +433,10 @@ where
     }
 }
 
-/// A parallel iterator producing elements in the union of `IndexSet`s.
+/// A parallel iterator producing elements in the union of [`IndexSet`]s.
 ///
-/// This `struct` is created by the [`par_union`] method on [`IndexSet`].
+/// This `struct` is created by the [`IndexSet::par_union`] method.
 /// See its documentation for more.
-///
-/// [`IndexSet`]: ../struct.IndexSet.html
-/// [`par_union`]: ../struct.IndexSet.html#method.par_union
 pub struct ParUnion<'a, T, S1, S2> {
     set1: &'a IndexSet<T, S1>,
     set2: &'a IndexSet<T, S2>,
@@ -476,8 +484,7 @@ where
 /// The following methods **require crate feature `"rayon"`**.
 impl<T, S> IndexSet<T, S>
 where
-    T: Hash + Eq + Send,
-    S: BuildHasher + Send,
+    T: Send,
 {
     /// Sort the set’s values in parallel by their default ordering.
     pub fn par_sort(&mut self)
@@ -540,9 +547,19 @@ where
         entries.par_sort_unstable_by(move |a, b| cmp(&a.key, &b.key));
         IntoParIter { entries }
     }
+
+    /// Sort the set’s values in place and in parallel, using a key extraction function.
+    pub fn par_sort_by_cached_key<K, F>(&mut self, sort_key: F)
+    where
+        K: Ord + Send,
+        F: Fn(&T) -> K + Sync,
+    {
+        self.with_entries(move |entries| {
+            entries.par_sort_by_cached_key(move |a| sort_key(&a.key));
+        });
+    }
 }
 
-/// Requires crate feature `"rayon"`.
 impl<T, S> FromParallelIterator<T> for IndexSet<T, S>
 where
     T: Eq + Hash + Send,
@@ -562,7 +579,6 @@ where
     }
 }
 
-/// Requires crate feature `"rayon"`.
 impl<T, S> ParallelExtend<T> for IndexSet<T, S>
 where
     T: Eq + Hash + Send,
@@ -578,7 +594,6 @@ where
     }
 }
 
-/// Requires crate feature `"rayon"`.
 impl<'a, T: 'a, S> ParallelExtend<&'a T> for IndexSet<T, S>
 where
     T: Copy + Eq + Hash + Send + Sync,
diff --git a/third_party/rust/indexmap/src/serde.rs b/third_party/rust/indexmap/src/serde.rs
index c6dd6d5ea0..25546d531b 100644
--- a/third_party/rust/indexmap/src/serde.rs
+++ b/third_party/rust/indexmap/src/serde.rs
@@ -1,3 +1,5 @@
+#![cfg_attr(docsrs, doc(cfg(feature = "serde")))]
+
 use serde::de::value::{MapDeserializer, SeqDeserializer};
 use serde::de::{
     Deserialize, Deserializer, Error, IntoDeserializer, MapAccess, SeqAccess, Visitor,
@@ -7,15 +9,30 @@ use serde::ser::{Serialize, Serializer};
 use core::fmt::{self, Formatter};
 use core::hash::{BuildHasher, Hash};
 use core::marker::PhantomData;
+use core::{cmp, mem};
+
+use crate::{Bucket, IndexMap, IndexSet};
+
+/// Limit our preallocated capacity from a deserializer `size_hint()`.
+///
+/// We do account for the `Bucket` overhead from its saved `hash` field, but we don't count the
+/// `RawTable` allocation or the fact that its raw capacity will be rounded up to a power of two.
+/// The "max" is an arbitrary choice anyway, not something that needs precise adherence.
+///
+/// This is based on the internal `serde::de::size_hint::cautious(hint)` function.
+pub(crate) fn cautious_capacity<K, V>(hint: Option<usize>) -> usize {
+    const MAX_PREALLOC_BYTES: usize = 1024 * 1024;
+
+    cmp::min(
+        hint.unwrap_or(0),
+        MAX_PREALLOC_BYTES / mem::size_of::<Bucket<K, V>>(),
+    )
+}
 
-use crate::IndexMap;
-
-/// Requires crate feature `"serde"` or `"serde-1"`
 impl<K, V, S> Serialize for IndexMap<K, V, S>
 where
-    K: Serialize + Hash + Eq,
+    K: Serialize,
     V: Serialize,
-    S: BuildHasher,
 {
     fn serialize<T>(&self, serializer: T) -> Result<T::Ok, T::Error>
     where
@@ -43,8 +60,8 @@ where
     where
         A: MapAccess<'de>,
     {
-        let mut values =
-            IndexMap::with_capacity_and_hasher(map.size_hint().unwrap_or(0), S::default());
+        let capacity = cautious_capacity::<K, V>(map.size_hint());
+        let mut values = IndexMap::with_capacity_and_hasher(capacity, S::default());
 
         while let Some((key, value)) = map.next_entry()? {
             values.insert(key, value);
@@ -54,7 +71,6 @@ where
     }
 }
 
-/// Requires crate feature `"serde"` or `"serde-1"`
 impl<'de, K, V, S> Deserialize<'de> for IndexMap<K, V, S>
 where
     K: Deserialize<'de> + Eq + Hash,
@@ -83,13 +99,9 @@ where
     }
 }
 
-use crate::IndexSet;
-
-/// Requires crate feature `"serde"` or `"serde-1"`
 impl<T, S> Serialize for IndexSet<T, S>
 where
-    T: Serialize + Hash + Eq,
-    S: BuildHasher,
+    T: Serialize,
 {
     fn serialize<Se>(&self, serializer: Se) -> Result<Se::Ok, Se::Error>
     where
@@ -116,8 +128,8 @@ where
     where
         A: SeqAccess<'de>,
     {
-        let mut values =
-            IndexSet::with_capacity_and_hasher(seq.size_hint().unwrap_or(0), S::default());
+        let capacity = cautious_capacity::<T, ()>(seq.size_hint());
+        let mut values = IndexSet::with_capacity_and_hasher(capacity, S::default());
 
         while let Some(value) = seq.next_element()? {
             values.insert(value);
@@ -127,7 +139,6 @@ where
     }
 }
 
-/// Requires crate feature `"serde"` or `"serde-1"`
 impl<'de, T, S> Deserialize<'de> for IndexSet<T, S>
 where
     T: Deserialize<'de> + Eq + Hash,
diff --git a/third_party/rust/indexmap/src/set.rs b/third_party/rust/indexmap/src/set.rs
index 3728947426..b5bd05f1bc 100644
--- a/third_party/rust/indexmap/src/set.rs
+++ b/third_party/rust/indexmap/src/set.rs
@@ -1,18 +1,32 @@
-//! A hash set implemented using `IndexMap`
+//! A hash set implemented using [`IndexMap`]
+
+mod iter;
+mod mutable;
+mod slice;
+
+#[cfg(test)]
+mod tests;
+
+pub use self::iter::{
+    Difference, Drain, Intersection, IntoIter, Iter, Splice, SymmetricDifference, Union,
+};
+pub use self::mutable::MutableValues;
+pub use self::slice::Slice;
 
 #[cfg(feature = "rayon")]
 pub use crate::rayon::set as rayon;
+use crate::TryReserveError;
 
-#[cfg(has_std)]
+#[cfg(feature = "std")]
 use std::collections::hash_map::RandomState;
 
-use crate::vec::{self, Vec};
+use crate::util::try_simplify_range;
+use alloc::boxed::Box;
+use alloc::vec::Vec;
 use core::cmp::Ordering;
 use core::fmt;
 use core::hash::{BuildHasher, Hash};
-use core::iter::{Chain, FusedIterator};
 use core::ops::{BitAnd, BitOr, BitXor, Index, RangeBounds, Sub};
-use core::slice;
 
 use super::{Entries, Equivalent, IndexMap};
 
@@ -21,8 +35,9 @@ type Bucket<T> = super::Bucket<T, ()>;
 /// A hash set where the iteration order of the values is independent of their
 /// hash values.
 ///
-/// The interface is closely compatible with the standard `HashSet`, but also
-/// has additional features.
+/// The interface is closely compatible with the standard
+/// [`HashSet`][std::collections::HashSet],
+/// but also has additional features.
 ///
 /// # Order
 ///
@@ -33,11 +48,12 @@ type Bucket<T> = super::Bucket<T, ()>;
 /// already present.
 ///
 /// All iterators traverse the set *in order*.  Set operation iterators like
-/// `union` produce a concatenated order, as do their matching "bitwise"
+/// [`IndexSet::union`] produce a concatenated order, as do their matching "bitwise"
 /// operators.  See their documentation for specifics.
 ///
 /// The insertion order is preserved, with **notable exceptions** like the
-/// `.remove()` or `.swap_remove()` methods. Methods such as `.sort_by()` of
+/// [`.remove()`][Self::remove] or [`.swap_remove()`][Self::swap_remove] methods.
+/// Methods such as [`.sort_by()`][Self::sort_by] of
 /// course result in a new order, depending on the sorting order.
 ///
 /// # Indices
@@ -46,6 +62,11 @@ type Bucket<T> = super::Bucket<T, ()>;
 /// `0..self.len()`. For example, the method `.get_full` looks up the index for
 /// a value, and the method `.get_index` looks up the value by index.
 ///
+/// # Complexity
+///
+/// Internally, `IndexSet<T, S>` just holds an [`IndexMap<T, (), S>`](IndexMap). Thus the complexity
+/// of the two are the same for most methods.
+///
 /// # Examples
 ///
 /// ```
@@ -59,11 +80,11 @@ type Bucket<T> = super::Bucket<T, ()>;
 /// assert!(letters.contains(&'u'));
 /// assert!(!letters.contains(&'y'));
 /// ```
-#[cfg(has_std)]
+#[cfg(feature = "std")]
 pub struct IndexSet<T, S = RandomState> {
     pub(crate) map: IndexMap<T, (), S>,
 }
-#[cfg(not(has_std))]
+#[cfg(not(feature = "std"))]
 pub struct IndexSet<T, S> {
     pub(crate) map: IndexMap<T, (), S>,
 }
@@ -114,17 +135,20 @@ impl<T, S> fmt::Debug for IndexSet<T, S>
 where
     T: fmt::Debug,
 {
+    #[cfg(not(feature = "test_debug"))]
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        if cfg!(not(feature = "test_debug")) {
-            f.debug_set().entries(self.iter()).finish()
-        } else {
-            // Let the inner `IndexMap` print all of its details
-            f.debug_struct("IndexSet").field("map", &self.map).finish()
-        }
+        f.debug_set().entries(self.iter()).finish()
+    }
+
+    #[cfg(feature = "test_debug")]
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        // Let the inner `IndexMap` print all of its details
+        f.debug_struct("IndexSet").field("map", &self.map).finish()
     }
 }
 
-#[cfg(has_std)]
+#[cfg(feature = "std")]
+#[cfg_attr(docsrs, doc(cfg(feature = "std")))]
 impl<T> IndexSet<T> {
     /// Create a new set. (Does not allocate.)
     pub fn new() -> Self {
@@ -165,6 +189,11 @@ impl<T, S> IndexSet<T, S> {
         }
     }
 
+    /// Return the number of elements the set can hold without reallocating.
+    ///
+    /// This number is a lower bound; the set might be able to hold more,
+    /// but is guaranteed to be able to hold at least this many.
+    ///
     /// Computes in **O(1)** time.
     pub fn capacity(&self) -> usize {
         self.map.capacity()
@@ -191,9 +220,7 @@ impl<T, S> IndexSet<T, S> {
 
     /// Return an iterator over the values of the set, in their order
     pub fn iter(&self) -> Iter<'_, T> {
-        Iter {
-            iter: self.map.as_entries().iter(),
-        }
+        Iter::new(self.as_entries())
     }
 
     /// Remove all elements in the set, while preserving its capacity.
@@ -213,7 +240,7 @@ impl<T, S> IndexSet<T, S> {
     /// Clears the `IndexSet` in the given index range, returning those values
     /// as a drain iterator.
     ///
-    /// The range may be any type that implements `RangeBounds<usize>`,
+    /// The range may be any type that implements [`RangeBounds<usize>`],
     /// including all of the `std::ops::Range*` types, or even a tuple pair of
     /// `Bound` start and end values. To drain the set entirely, use `RangeFull`
     /// like `set.drain(..)`.
@@ -227,9 +254,7 @@ impl<T, S> IndexSet<T, S> {
     where
         R: RangeBounds<usize>,
     {
-        Drain {
-            iter: self.map.drain(range).iter,
-        }
+        Drain::new(self.map.core.drain(range))
     }
 
     /// Splits the collection into two at the given index.
@@ -247,13 +272,7 @@ impl<T, S> IndexSet<T, S> {
             map: self.map.split_off(at),
         }
     }
-}
 
-impl<T, S> IndexSet<T, S>
-where
-    T: Hash + Eq,
-    S: BuildHasher,
-{
     /// Reserve capacity for `additional` more values.
     ///
     /// Computes in **O(n)** time.
@@ -261,6 +280,37 @@ where
         self.map.reserve(additional);
     }
 
+    /// Reserve capacity for `additional` more values, without over-allocating.
+    ///
+    /// Unlike `reserve`, this does not deliberately over-allocate the entry capacity to avoid
+    /// frequent re-allocations. However, the underlying data structures may still have internal
+    /// capacity requirements, and the allocator itself may give more space than requested, so this
+    /// cannot be relied upon to be precisely minimal.
+    ///
+    /// Computes in **O(n)** time.
+    pub fn reserve_exact(&mut self, additional: usize) {
+        self.map.reserve_exact(additional);
+    }
+
+    /// Try to reserve capacity for `additional` more values.
+    ///
+    /// Computes in **O(n)** time.
+    pub fn try_reserve(&mut self, additional: usize) -> Result<(), TryReserveError> {
+        self.map.try_reserve(additional)
+    }
+
+    /// Try to reserve capacity for `additional` more values, without over-allocating.
+    ///
+    /// Unlike `try_reserve`, this does not deliberately over-allocate the entry capacity to avoid
+    /// frequent re-allocations. However, the underlying data structures may still have internal
+    /// capacity requirements, and the allocator itself may give more space than requested, so this
+    /// cannot be relied upon to be precisely minimal.
+    ///
+    /// Computes in **O(n)** time.
+    pub fn try_reserve_exact(&mut self, additional: usize) -> Result<(), TryReserveError> {
+        self.map.try_reserve_exact(additional)
+    }
+
     /// Shrink the capacity of the set as much as possible.
     ///
     /// Computes in **O(n)** time.
@@ -274,7 +324,13 @@ where
     pub fn shrink_to(&mut self, min_capacity: usize) {
         self.map.shrink_to(min_capacity);
     }
+}
 
+impl<T, S> IndexSet<T, S>
+where
+    T: Hash + Eq,
+    S: BuildHasher,
+{
     /// Insert the value into the set.
     ///
     /// If an equivalent item already exists in the set, it returns
@@ -297,15 +353,69 @@ where
     ///
     /// Computes in **O(1)** time (amortized average).
     pub fn insert_full(&mut self, value: T) -> (usize, bool) {
-        use super::map::Entry::*;
-
-        match self.map.entry(value) {
-            Occupied(e) => (e.index(), false),
-            Vacant(e) => {
-                let index = e.index();
-                e.insert(());
-                (index, true)
-            }
+        let (index, existing) = self.map.insert_full(value, ());
+        (index, existing.is_none())
+    }
+
+    /// Insert the value into the set at its ordered position among sorted values.
+    ///
+    /// This is equivalent to finding the position with
+    /// [`binary_search`][Self::binary_search], and if needed calling
+    /// [`shift_insert`][Self::shift_insert] for a new value.
+    ///
+    /// If the sorted item is found in the set, it returns the index of that
+    /// existing item and `false`, without any change. Otherwise, it inserts the
+    /// new item and returns its sorted index and `true`.
+    ///
+    /// If the existing items are **not** already sorted, then the insertion
+    /// index is unspecified (like [`slice::binary_search`]), but the value
+    /// is moved to or inserted at that position regardless.
+    ///
+    /// Computes in **O(n)** time (average). Instead of repeating calls to
+    /// `insert_sorted`, it may be faster to call batched [`insert`][Self::insert]
+    /// or [`extend`][Self::extend] and only call [`sort`][Self::sort] or
+    /// [`sort_unstable`][Self::sort_unstable] once.
+    pub fn insert_sorted(&mut self, value: T) -> (usize, bool)
+    where
+        T: Ord,
+    {
+        let (index, existing) = self.map.insert_sorted(value, ());
+        (index, existing.is_none())
+    }
+
+    /// Insert the value into the set at the given index.
+    ///
+    /// If an equivalent item already exists in the set, it returns
+    /// `false` leaving the original value in the set, but moving it to
+    /// the new position in the set. Otherwise, it inserts the new
+    /// item at the given index and returns `true`.
+    ///
+    /// ***Panics*** if `index` is out of bounds.
+    ///
+    /// Computes in **O(n)** time (average).
+    pub fn shift_insert(&mut self, index: usize, value: T) -> bool {
+        self.map.shift_insert(index, value, ()).is_none()
+    }
+
+    /// Adds a value to the set, replacing the existing value, if any, that is
+    /// equal to the given one, without altering its insertion order. Returns
+    /// the replaced value.
+    ///
+    /// Computes in **O(1)** time (average).
+    pub fn replace(&mut self, value: T) -> Option<T> {
+        self.replace_full(value).1
+    }
+
+    /// Adds a value to the set, replacing the existing value, if any, that is
+    /// equal to the given one, without altering its insertion order. Returns
+    /// the index of the item and its replaced value.
+    ///
+    /// Computes in **O(1)** time (average).
+    pub fn replace_full(&mut self, value: T) -> (usize, Option<T>) {
+        let hash = self.map.hash(&value);
+        match self.map.core.replace_full(hash, value, ()) {
+            (i, Some((replaced, ()))) => (i, Some(replaced)),
+            (i, None) => (i, None),
         }
     }
 
@@ -316,10 +426,7 @@ where
     where
         S2: BuildHasher,
     {
-        Difference {
-            iter: self.iter(),
-            other,
-        }
+        Difference::new(self, other)
     }
 
     /// Return an iterator over the values that are in `self` or `other`,
@@ -334,9 +441,7 @@ where
     where
         S2: BuildHasher,
     {
-        SymmetricDifference {
-            iter: self.difference(other).chain(other.difference(self)),
-        }
+        SymmetricDifference::new(self, other)
     }
 
     /// Return an iterator over the values that are in both `self` and `other`.
@@ -346,10 +451,7 @@ where
     where
         S2: BuildHasher,
     {
-        Intersection {
-            iter: self.iter(),
-            other,
-        }
+        Intersection::new(self, other)
     }
 
     /// Return an iterator over all values that are in `self` or `other`.
@@ -360,17 +462,57 @@ where
     where
         S2: BuildHasher,
     {
-        Union {
-            iter: self.iter().chain(other.difference(self)),
-        }
+        Union::new(self, other)
     }
 
+    /// Creates a splicing iterator that replaces the specified range in the set
+    /// with the given `replace_with` iterator and yields the removed items.
+    /// `replace_with` does not need to be the same length as `range`.
+    ///
+    /// The `range` is removed even if the iterator is not consumed until the
+    /// end. It is unspecified how many elements are removed from the set if the
+    /// `Splice` value is leaked.
+    ///
+    /// The input iterator `replace_with` is only consumed when the `Splice`
+    /// value is dropped. If a value from the iterator matches an existing entry
+    /// in the set (outside of `range`), then the original will be unchanged.
+    /// Otherwise, the new value will be inserted in the replaced `range`.
+    ///
+    /// ***Panics*** if the starting point is greater than the end point or if
+    /// the end point is greater than the length of the set.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use indexmap::IndexSet;
+    ///
+    /// let mut set = IndexSet::from([0, 1, 2, 3, 4]);
+    /// let new = [5, 4, 3, 2, 1];
+    /// let removed: Vec<_> = set.splice(2..4, new).collect();
+    ///
+    /// // 1 and 4 kept their positions, while 5, 3, and 2 were newly inserted.
+    /// assert!(set.into_iter().eq([0, 1, 5, 3, 2, 4]));
+    /// assert_eq!(removed, &[2, 3]);
+    /// ```
+    pub fn splice<R, I>(&mut self, range: R, replace_with: I) -> Splice<'_, I::IntoIter, T, S>
+    where
+        R: RangeBounds<usize>,
+        I: IntoIterator<Item = T>,
+    {
+        Splice::new(self, range, replace_with.into_iter())
+    }
+}
+
+impl<T, S> IndexSet<T, S>
+where
+    S: BuildHasher,
+{
     /// Return `true` if an equivalent to `value` exists in the set.
     ///
     /// Computes in **O(1)** time (average).
-    pub fn contains<Q: ?Sized>(&self, value: &Q) -> bool
+    pub fn contains<Q>(&self, value: &Q) -> bool
     where
-        Q: Hash + Equivalent<T>,
+        Q: ?Sized + Hash + Equivalent<T>,
     {
         self.map.contains_key(value)
     }
@@ -379,97 +521,74 @@ where
     /// else `None`.
     ///
     /// Computes in **O(1)** time (average).
-    pub fn get<Q: ?Sized>(&self, value: &Q) -> Option<&T>
+    pub fn get<Q>(&self, value: &Q) -> Option<&T>
     where
-        Q: Hash + Equivalent<T>,
+        Q: ?Sized + Hash + Equivalent<T>,
     {
         self.map.get_key_value(value).map(|(x, &())| x)
     }
 
     /// Return item index and value
-    pub fn get_full<Q: ?Sized>(&self, value: &Q) -> Option<(usize, &T)>
+    pub fn get_full<Q>(&self, value: &Q) -> Option<(usize, &T)>
     where
-        Q: Hash + Equivalent<T>,
+        Q: ?Sized + Hash + Equivalent<T>,
     {
         self.map.get_full(value).map(|(i, x, &())| (i, x))
     }
 
     /// Return item index, if it exists in the set
-    pub fn get_index_of<Q: ?Sized>(&self, value: &Q) -> Option<usize>
+    ///
+    /// Computes in **O(1)** time (average).
+    pub fn get_index_of<Q>(&self, value: &Q) -> Option<usize>
     where
-        Q: Hash + Equivalent<T>,
+        Q: ?Sized + Hash + Equivalent<T>,
     {
         self.map.get_index_of(value)
     }
 
-    /// Adds a value to the set, replacing the existing value, if any, that is
-    /// equal to the given one, without altering its insertion order. Returns
-    /// the replaced value.
-    ///
-    /// Computes in **O(1)** time (average).
-    pub fn replace(&mut self, value: T) -> Option<T> {
-        self.replace_full(value).1
-    }
-
-    /// Adds a value to the set, replacing the existing value, if any, that is
-    /// equal to the given one, without altering its insertion order. Returns
-    /// the index of the item and its replaced value.
-    ///
-    /// Computes in **O(1)** time (average).
-    pub fn replace_full(&mut self, value: T) -> (usize, Option<T>) {
-        use super::map::Entry::*;
-
-        match self.map.entry(value) {
-            Vacant(e) => {
-                let index = e.index();
-                e.insert(());
-                (index, None)
-            }
-            Occupied(e) => (e.index(), Some(e.replace_key())),
-        }
-    }
-
     /// Remove the value from the set, and return `true` if it was present.
     ///
-    /// **NOTE:** This is equivalent to `.swap_remove(value)`, if you want
-    /// to preserve the order of the values in the set, use `.shift_remove(value)`.
-    ///
-    /// Computes in **O(1)** time (average).
-    pub fn remove<Q: ?Sized>(&mut self, value: &Q) -> bool
+    /// **NOTE:** This is equivalent to [`.swap_remove(value)`][Self::swap_remove], replacing this
+    /// value's position with the last element, and it is deprecated in favor of calling that
+    /// explicitly. If you need to preserve the relative order of the values in the set, use
+    /// [`.shift_remove(value)`][Self::shift_remove] instead.
+    #[deprecated(note = "`remove` disrupts the set order -- \
+        use `swap_remove` or `shift_remove` for explicit behavior.")]
+    pub fn remove<Q>(&mut self, value: &Q) -> bool
     where
-        Q: Hash + Equivalent<T>,
+        Q: ?Sized + Hash + Equivalent<T>,
     {
         self.swap_remove(value)
     }
 
     /// Remove the value from the set, and return `true` if it was present.
     ///
-    /// Like `Vec::swap_remove`, the value is removed by swapping it with the
+    /// Like [`Vec::swap_remove`], the value is removed by swapping it with the
     /// last element of the set and popping it off. **This perturbs
     /// the position of what used to be the last element!**
     ///
     /// Return `false` if `value` was not in the set.
     ///
     /// Computes in **O(1)** time (average).
-    pub fn swap_remove<Q: ?Sized>(&mut self, value: &Q) -> bool
+    pub fn swap_remove<Q>(&mut self, value: &Q) -> bool
     where
-        Q: Hash + Equivalent<T>,
+        Q: ?Sized + Hash + Equivalent<T>,
     {
         self.map.swap_remove(value).is_some()
     }
 
     /// Remove the value from the set, and return `true` if it was present.
     ///
-    /// Like `Vec::remove`, the value is removed by shifting all of the
+    /// Like [`Vec::remove`], the value is removed by shifting all of the
     /// elements that follow it, preserving their relative order.
     /// **This perturbs the index of all of those elements!**
     ///
     /// Return `false` if `value` was not in the set.
     ///
     /// Computes in **O(n)** time (average).
-    pub fn shift_remove<Q: ?Sized>(&mut self, value: &Q) -> bool
+    pub fn shift_remove<Q>(&mut self, value: &Q) -> bool
     where
-        Q: Hash + Equivalent<T>,
+        Q: ?Sized + Hash + Equivalent<T>,
     {
         self.map.shift_remove(value).is_some()
     }
@@ -477,14 +596,15 @@ where
     /// Removes and returns the value in the set, if any, that is equal to the
     /// given one.
     ///
-    /// **NOTE:** This is equivalent to `.swap_take(value)`, if you need to
-    /// preserve the order of the values in the set, use `.shift_take(value)`
-    /// instead.
-    ///
-    /// Computes in **O(1)** time (average).
-    pub fn take<Q: ?Sized>(&mut self, value: &Q) -> Option<T>
+    /// **NOTE:** This is equivalent to [`.swap_take(value)`][Self::swap_take], replacing this
+    /// value's position with the last element, and it is deprecated in favor of calling that
+    /// explicitly. If you need to preserve the relative order of the values in the set, use
+    /// [`.shift_take(value)`][Self::shift_take] instead.
+    #[deprecated(note = "`take` disrupts the set order -- \
+        use `swap_take` or `shift_take` for explicit behavior.")]
+    pub fn take<Q>(&mut self, value: &Q) -> Option<T>
     where
-        Q: Hash + Equivalent<T>,
+        Q: ?Sized + Hash + Equivalent<T>,
     {
         self.swap_take(value)
     }
@@ -492,16 +612,16 @@ where
     /// Removes and returns the value in the set, if any, that is equal to the
     /// given one.
     ///
-    /// Like `Vec::swap_remove`, the value is removed by swapping it with the
+    /// Like [`Vec::swap_remove`], the value is removed by swapping it with the
     /// last element of the set and popping it off. **This perturbs
     /// the position of what used to be the last element!**
     ///
     /// Return `None` if `value` was not in the set.
     ///
     /// Computes in **O(1)** time (average).
-    pub fn swap_take<Q: ?Sized>(&mut self, value: &Q) -> Option<T>
+    pub fn swap_take<Q>(&mut self, value: &Q) -> Option<T>
     where
-        Q: Hash + Equivalent<T>,
+        Q: ?Sized + Hash + Equivalent<T>,
     {
         self.map.swap_remove_entry(value).map(|(x, ())| x)
     }
@@ -509,48 +629,50 @@ where
     /// Removes and returns the value in the set, if any, that is equal to the
     /// given one.
     ///
-    /// Like `Vec::remove`, the value is removed by shifting all of the
+    /// Like [`Vec::remove`], the value is removed by shifting all of the
     /// elements that follow it, preserving their relative order.
     /// **This perturbs the index of all of those elements!**
     ///
     /// Return `None` if `value` was not in the set.
     ///
     /// Computes in **O(n)** time (average).
-    pub fn shift_take<Q: ?Sized>(&mut self, value: &Q) -> Option<T>
+    pub fn shift_take<Q>(&mut self, value: &Q) -> Option<T>
     where
-        Q: Hash + Equivalent<T>,
+        Q: ?Sized + Hash + Equivalent<T>,
     {
         self.map.shift_remove_entry(value).map(|(x, ())| x)
     }
 
     /// Remove the value from the set return it and the index it had.
     ///
-    /// Like `Vec::swap_remove`, the value is removed by swapping it with the
+    /// Like [`Vec::swap_remove`], the value is removed by swapping it with the
     /// last element of the set and popping it off. **This perturbs
     /// the position of what used to be the last element!**
     ///
     /// Return `None` if `value` was not in the set.
-    pub fn swap_remove_full<Q: ?Sized>(&mut self, value: &Q) -> Option<(usize, T)>
+    pub fn swap_remove_full<Q>(&mut self, value: &Q) -> Option<(usize, T)>
     where
-        Q: Hash + Equivalent<T>,
+        Q: ?Sized + Hash + Equivalent<T>,
     {
         self.map.swap_remove_full(value).map(|(i, x, ())| (i, x))
     }
 
     /// Remove the value from the set return it and the index it had.
     ///
-    /// Like `Vec::remove`, the value is removed by shifting all of the
+    /// Like [`Vec::remove`], the value is removed by shifting all of the
     /// elements that follow it, preserving their relative order.
     /// **This perturbs the index of all of those elements!**
     ///
     /// Return `None` if `value` was not in the set.
-    pub fn shift_remove_full<Q: ?Sized>(&mut self, value: &Q) -> Option<(usize, T)>
+    pub fn shift_remove_full<Q>(&mut self, value: &Q) -> Option<(usize, T)>
     where
-        Q: Hash + Equivalent<T>,
+        Q: ?Sized + Hash + Equivalent<T>,
     {
         self.map.shift_remove_full(value).map(|(i, x, ())| (i, x))
     }
+}
 
+impl<T, S> IndexSet<T, S> {
     /// Remove the last value
     ///
     /// This preserves the order of the remaining elements.
@@ -576,6 +698,10 @@ where
 
     /// Sort the set’s values by their default ordering.
     ///
+    /// This is a stable sort -- but equivalent values should not normally coexist in
+    /// a set at all, so [`sort_unstable`][Self::sort_unstable] is preferred
+    /// because it is generally faster and doesn't allocate auxiliary memory.
+    ///
     /// See [`sort_by`](Self::sort_by) for details.
     pub fn sort(&mut self)
     where
@@ -604,9 +730,7 @@ where
     {
         let mut entries = self.into_entries();
         entries.sort_by(move |a, b| cmp(&a.key, &b.key));
-        IntoIter {
-            iter: entries.into_iter(),
-        }
+        IntoIter::new(entries)
     }
 
     /// Sort the set's values by their default ordering.
@@ -619,7 +743,7 @@ where
         self.map.sort_unstable_keys()
     }
 
-    /// Sort the set's values in place using the comparison funtion `cmp`.
+    /// Sort the set's values in place using the comparison function `cmp`.
     ///
     /// Computes in **O(n log n)** time. The sort is unstable.
     pub fn sort_unstable_by<F>(&mut self, mut cmp: F)
@@ -637,9 +761,82 @@ where
     {
         let mut entries = self.into_entries();
         entries.sort_unstable_by(move |a, b| cmp(&a.key, &b.key));
-        IntoIter {
-            iter: entries.into_iter(),
-        }
+        IntoIter::new(entries)
+    }
+
+    /// Sort the set’s values in place using a key extraction function.
+    ///
+    /// During sorting, the function is called at most once per entry, by using temporary storage
+    /// to remember the results of its evaluation. The order of calls to the function is
+    /// unspecified and may change between versions of `indexmap` or the standard library.
+    ///
+    /// Computes in **O(m n + n log n + c)** time () and **O(n)** space, where the function is
+    /// **O(m)**, *n* is the length of the map, and *c* the capacity. The sort is stable.
+    pub fn sort_by_cached_key<K, F>(&mut self, mut sort_key: F)
+    where
+        K: Ord,
+        F: FnMut(&T) -> K,
+    {
+        self.with_entries(move |entries| {
+            entries.sort_by_cached_key(move |a| sort_key(&a.key));
+        });
+    }
+
+    /// Search over a sorted set for a value.
+    ///
+    /// Returns the position where that value is present, or the position where it can be inserted
+    /// to maintain the sort. See [`slice::binary_search`] for more details.
+    ///
+    /// Computes in **O(log(n))** time, which is notably less scalable than looking the value up
+    /// using [`get_index_of`][IndexSet::get_index_of], but this can also position missing values.
+    pub fn binary_search(&self, x: &T) -> Result<usize, usize>
+    where
+        T: Ord,
+    {
+        self.as_slice().binary_search(x)
+    }
+
+    /// Search over a sorted set with a comparator function.
+    ///
+    /// Returns the position where that value is present, or the position where it can be inserted
+    /// to maintain the sort. See [`slice::binary_search_by`] for more details.
+    ///
+    /// Computes in **O(log(n))** time.
+    #[inline]
+    pub fn binary_search_by<'a, F>(&'a self, f: F) -> Result<usize, usize>
+    where
+        F: FnMut(&'a T) -> Ordering,
+    {
+        self.as_slice().binary_search_by(f)
+    }
+
+    /// Search over a sorted set with an extraction function.
+    ///
+    /// Returns the position where that value is present, or the position where it can be inserted
+    /// to maintain the sort. See [`slice::binary_search_by_key`] for more details.
+    ///
+    /// Computes in **O(log(n))** time.
+    #[inline]
+    pub fn binary_search_by_key<'a, B, F>(&'a self, b: &B, f: F) -> Result<usize, usize>
+    where
+        F: FnMut(&'a T) -> B,
+        B: Ord,
+    {
+        self.as_slice().binary_search_by_key(b, f)
+    }
+
+    /// Returns the index of the partition point of a sorted set according to the given predicate
+    /// (the index of the first element of the second partition).
+    ///
+    /// See [`slice::partition_point`] for more details.
+    ///
+    /// Computes in **O(log(n))** time.
+    #[must_use]
+    pub fn partition_point<P>(&self, pred: P) -> usize
+    where
+        P: FnMut(&T) -> bool,
+    {
+        self.as_slice().partition_point(pred)
     }
 
     /// Reverses the order of the set’s values in place.
@@ -648,9 +845,21 @@ where
     pub fn reverse(&mut self) {
         self.map.reverse()
     }
-}
 
-impl<T, S> IndexSet<T, S> {
+    /// Returns a slice of all the values in the set.
+    ///
+    /// Computes in **O(1)** time.
+    pub fn as_slice(&self) -> &Slice<T> {
+        Slice::from_slice(self.as_entries())
+    }
+
+    /// Converts into a boxed slice of all the values in the set.
+    ///
+    /// Note that this will drop the inner hash table and any excess capacity.
+    pub fn into_boxed_slice(self) -> Box<Slice<T>> {
+        Slice::from_boxed(self.into_entries().into_boxed_slice())
+    }
+
     /// Get a value by index
     ///
     /// Valid indices are *0 <= index < self.len()*
@@ -660,6 +869,17 @@ impl<T, S> IndexSet<T, S> {
         self.as_entries().get(index).map(Bucket::key_ref)
     }
 
+    /// Returns a slice of values in the given range of indices.
+    ///
+    /// Valid indices are *0 <= index < self.len()*
+    ///
+    /// Computes in **O(1)** time.
+    pub fn get_range<R: RangeBounds<usize>>(&self, range: R) -> Option<&Slice<T>> {
+        let entries = self.as_entries();
+        let range = try_simplify_range(range, entries.len())?;
+        entries.get(range).map(Slice::from_slice)
+    }
+
     /// Get the first value
     ///
     /// Computes in **O(1)** time.
@@ -678,7 +898,7 @@ impl<T, S> IndexSet<T, S> {
     ///
     /// Valid indices are *0 <= index < self.len()*
     ///
-    /// Like `Vec::swap_remove`, the value is removed by swapping it with the
+    /// Like [`Vec::swap_remove`], the value is removed by swapping it with the
     /// last element of the set and popping it off. **This perturbs
     /// the position of what used to be the last element!**
     ///
@@ -691,7 +911,7 @@ impl<T, S> IndexSet<T, S> {
     ///
     /// Valid indices are *0 <= index < self.len()*
     ///
-    /// Like `Vec::remove`, the value is removed by shifting all of the
+    /// Like [`Vec::remove`], the value is removed by shifting all of the
     /// elements that follow it, preserving their relative order.
     /// **This perturbs the index of all of those elements!**
     ///
@@ -716,12 +936,14 @@ impl<T, S> IndexSet<T, S> {
     /// Swaps the position of two values in the set.
     ///
     /// ***Panics*** if `a` or `b` are out of bounds.
+    ///
+    /// Computes in **O(1)** time (average).
     pub fn swap_indices(&mut self, a: usize, b: usize) {
         self.map.swap_indices(a, b)
     }
 }
 
-/// Access `IndexSet` values at indexed positions.
+/// Access [`IndexSet`] values at indexed positions.
 ///
 /// # Examples
 ///
@@ -761,141 +983,6 @@ impl<T, S> Index<usize> for IndexSet<T, S> {
     }
 }
 
-/// An owning iterator over the items of a `IndexSet`.
-///
-/// This `struct` is created by the [`into_iter`] method on [`IndexSet`]
-/// (provided by the `IntoIterator` trait). See its documentation for more.
-///
-/// [`IndexSet`]: struct.IndexSet.html
-/// [`into_iter`]: struct.IndexSet.html#method.into_iter
-pub struct IntoIter<T> {
-    iter: vec::IntoIter<Bucket<T>>,
-}
-
-impl<T> Iterator for IntoIter<T> {
-    type Item = T;
-
-    iterator_methods!(Bucket::key);
-}
-
-impl<T> DoubleEndedIterator for IntoIter<T> {
-    double_ended_iterator_methods!(Bucket::key);
-}
-
-impl<T> ExactSizeIterator for IntoIter<T> {
-    fn len(&self) -> usize {
-        self.iter.len()
-    }
-}
-
-impl<T> FusedIterator for IntoIter<T> {}
-
-impl<T: fmt::Debug> fmt::Debug for IntoIter<T> {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        let iter = self.iter.as_slice().iter().map(Bucket::key_ref);
-        f.debug_list().entries(iter).finish()
-    }
-}
-
-/// An iterator over the items of a `IndexSet`.
-///
-/// This `struct` is created by the [`iter`] method on [`IndexSet`].
-/// See its documentation for more.
-///
-/// [`IndexSet`]: struct.IndexSet.html
-/// [`iter`]: struct.IndexSet.html#method.iter
-pub struct Iter<'a, T> {
-    iter: slice::Iter<'a, Bucket<T>>,
-}
-
-impl<'a, T> Iterator for Iter<'a, T> {
-    type Item = &'a T;
-
-    iterator_methods!(Bucket::key_ref);
-}
-
-impl<T> DoubleEndedIterator for Iter<'_, T> {
-    double_ended_iterator_methods!(Bucket::key_ref);
-}
-
-impl<T> ExactSizeIterator for Iter<'_, T> {
-    fn len(&self) -> usize {
-        self.iter.len()
-    }
-}
-
-impl<T> FusedIterator for Iter<'_, T> {}
-
-impl<T> Clone for Iter<'_, T> {
-    fn clone(&self) -> Self {
-        Iter {
-            iter: self.iter.clone(),
-        }
-    }
-}
-
-impl<T: fmt::Debug> fmt::Debug for Iter<'_, T> {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        f.debug_list().entries(self.clone()).finish()
-    }
-}
-
-/// A draining iterator over the items of a `IndexSet`.
-///
-/// This `struct` is created by the [`drain`] method on [`IndexSet`].
-/// See its documentation for more.
-///
-/// [`IndexSet`]: struct.IndexSet.html
-/// [`drain`]: struct.IndexSet.html#method.drain
-pub struct Drain<'a, T> {
-    iter: vec::Drain<'a, Bucket<T>>,
-}
-
-impl<T> Iterator for Drain<'_, T> {
-    type Item = T;
-
-    iterator_methods!(Bucket::key);
-}
-
-impl<T> DoubleEndedIterator for Drain<'_, T> {
-    double_ended_iterator_methods!(Bucket::key);
-}
-
-impl<T> ExactSizeIterator for Drain<'_, T> {
-    fn len(&self) -> usize {
-        self.iter.len()
-    }
-}
-
-impl<T> FusedIterator for Drain<'_, T> {}
-
-impl<T: fmt::Debug> fmt::Debug for Drain<'_, T> {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        let iter = self.iter.as_slice().iter().map(Bucket::key_ref);
-        f.debug_list().entries(iter).finish()
-    }
-}
-
-impl<'a, T, S> IntoIterator for &'a IndexSet<T, S> {
-    type Item = &'a T;
-    type IntoIter = Iter<'a, T>;
-
-    fn into_iter(self) -> Self::IntoIter {
-        self.iter()
-    }
-}
-
-impl<T, S> IntoIterator for IndexSet<T, S> {
-    type Item = T;
-    type IntoIter = IntoIter<T>;
-
-    fn into_iter(self) -> Self::IntoIter {
-        IntoIter {
-            iter: self.into_entries().into_iter(),
-        }
-    }
-}
-
 impl<T, S> FromIterator<T> for IndexSet<T, S>
 where
     T: Hash + Eq,
@@ -909,7 +996,8 @@ where
     }
 }
 
-#[cfg(has_std)]
+#[cfg(feature = "std")]
+#[cfg_attr(docsrs, doc(cfg(feature = "std")))]
 impl<T, const N: usize> From<[T; N]> for IndexSet<T, RandomState>
 where
     T: Eq + Hash,
@@ -954,7 +1042,7 @@ impl<T, S> Default for IndexSet<T, S>
 where
     S: Default,
 {
-    /// Return an empty `IndexSet`
+    /// Return an empty [`IndexSet`]
     fn default() -> Self {
         IndexSet {
             map: IndexMap::default(),
@@ -1014,310 +1102,6 @@ where
     }
 }
 
-/// A lazy iterator producing elements in the difference of `IndexSet`s.
-///
-/// This `struct` is created by the [`difference`] method on [`IndexSet`].
-/// See its documentation for more.
-///
-/// [`IndexSet`]: struct.IndexSet.html
-/// [`difference`]: struct.IndexSet.html#method.difference
-pub struct Difference<'a, T, S> {
-    iter: Iter<'a, T>,
-    other: &'a IndexSet<T, S>,
-}
-
-impl<'a, T, S> Iterator for Difference<'a, T, S>
-where
-    T: Eq + Hash,
-    S: BuildHasher,
-{
-    type Item = &'a T;
-
-    fn next(&mut self) -> Option<Self::Item> {
-        while let Some(item) = self.iter.next() {
-            if !self.other.contains(item) {
-                return Some(item);
-            }
-        }
-        None
-    }
-
-    fn size_hint(&self) -> (usize, Option<usize>) {
-        (0, self.iter.size_hint().1)
-    }
-}
-
-impl<T, S> DoubleEndedIterator for Difference<'_, T, S>
-where
-    T: Eq + Hash,
-    S: BuildHasher,
-{
-    fn next_back(&mut self) -> Option<Self::Item> {
-        while let Some(item) = self.iter.next_back() {
-            if !self.other.contains(item) {
-                return Some(item);
-            }
-        }
-        None
-    }
-}
-
-impl<T, S> FusedIterator for Difference<'_, T, S>
-where
-    T: Eq + Hash,
-    S: BuildHasher,
-{
-}
-
-impl<T, S> Clone for Difference<'_, T, S> {
-    fn clone(&self) -> Self {
-        Difference {
-            iter: self.iter.clone(),
-            ..*self
-        }
-    }
-}
-
-impl<T, S> fmt::Debug for Difference<'_, T, S>
-where
-    T: fmt::Debug + Eq + Hash,
-    S: BuildHasher,
-{
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        f.debug_list().entries(self.clone()).finish()
-    }
-}
-
-/// A lazy iterator producing elements in the intersection of `IndexSet`s.
-///
-/// This `struct` is created by the [`intersection`] method on [`IndexSet`].
-/// See its documentation for more.
-///
-/// [`IndexSet`]: struct.IndexSet.html
-/// [`intersection`]: struct.IndexSet.html#method.intersection
-pub struct Intersection<'a, T, S> {
-    iter: Iter<'a, T>,
-    other: &'a IndexSet<T, S>,
-}
-
-impl<'a, T, S> Iterator for Intersection<'a, T, S>
-where
-    T: Eq + Hash,
-    S: BuildHasher,
-{
-    type Item = &'a T;
-
-    fn next(&mut self) -> Option<Self::Item> {
-        while let Some(item) = self.iter.next() {
-            if self.other.contains(item) {
-                return Some(item);
-            }
-        }
-        None
-    }
-
-    fn size_hint(&self) -> (usize, Option<usize>) {
-        (0, self.iter.size_hint().1)
-    }
-}
-
-impl<T, S> DoubleEndedIterator for Intersection<'_, T, S>
-where
-    T: Eq + Hash,
-    S: BuildHasher,
-{
-    fn next_back(&mut self) -> Option<Self::Item> {
-        while let Some(item) = self.iter.next_back() {
-            if self.other.contains(item) {
-                return Some(item);
-            }
-        }
-        None
-    }
-}
-
-impl<T, S> FusedIterator for Intersection<'_, T, S>
-where
-    T: Eq + Hash,
-    S: BuildHasher,
-{
-}
-
-impl<T, S> Clone for Intersection<'_, T, S> {
-    fn clone(&self) -> Self {
-        Intersection {
-            iter: self.iter.clone(),
-            ..*self
-        }
-    }
-}
-
-impl<T, S> fmt::Debug for Intersection<'_, T, S>
-where
-    T: fmt::Debug + Eq + Hash,
-    S: BuildHasher,
-{
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        f.debug_list().entries(self.clone()).finish()
-    }
-}
-
-/// A lazy iterator producing elements in the symmetric difference of `IndexSet`s.
-///
-/// This `struct` is created by the [`symmetric_difference`] method on
-/// [`IndexSet`]. See its documentation for more.
-///
-/// [`IndexSet`]: struct.IndexSet.html
-/// [`symmetric_difference`]: struct.IndexSet.html#method.symmetric_difference
-pub struct SymmetricDifference<'a, T, S1, S2> {
-    iter: Chain<Difference<'a, T, S2>, Difference<'a, T, S1>>,
-}
-
-impl<'a, T, S1, S2> Iterator for SymmetricDifference<'a, T, S1, S2>
-where
-    T: Eq + Hash,
-    S1: BuildHasher,
-    S2: BuildHasher,
-{
-    type Item = &'a T;
-
-    fn next(&mut self) -> Option<Self::Item> {
-        self.iter.next()
-    }
-
-    fn size_hint(&self) -> (usize, Option<usize>) {
-        self.iter.size_hint()
-    }
-
-    fn fold<B, F>(self, init: B, f: F) -> B
-    where
-        F: FnMut(B, Self::Item) -> B,
-    {
-        self.iter.fold(init, f)
-    }
-}
-
-impl<T, S1, S2> DoubleEndedIterator for SymmetricDifference<'_, T, S1, S2>
-where
-    T: Eq + Hash,
-    S1: BuildHasher,
-    S2: BuildHasher,
-{
-    fn next_back(&mut self) -> Option<Self::Item> {
-        self.iter.next_back()
-    }
-
-    fn rfold<B, F>(self, init: B, f: F) -> B
-    where
-        F: FnMut(B, Self::Item) -> B,
-    {
-        self.iter.rfold(init, f)
-    }
-}
-
-impl<T, S1, S2> FusedIterator for SymmetricDifference<'_, T, S1, S2>
-where
-    T: Eq + Hash,
-    S1: BuildHasher,
-    S2: BuildHasher,
-{
-}
-
-impl<T, S1, S2> Clone for SymmetricDifference<'_, T, S1, S2> {
-    fn clone(&self) -> Self {
-        SymmetricDifference {
-            iter: self.iter.clone(),
-        }
-    }
-}
-
-impl<T, S1, S2> fmt::Debug for SymmetricDifference<'_, T, S1, S2>
-where
-    T: fmt::Debug + Eq + Hash,
-    S1: BuildHasher,
-    S2: BuildHasher,
-{
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        f.debug_list().entries(self.clone()).finish()
-    }
-}
-
-/// A lazy iterator producing elements in the union of `IndexSet`s.
-///
-/// This `struct` is created by the [`union`] method on [`IndexSet`].
-/// See its documentation for more.
-///
-/// [`IndexSet`]: struct.IndexSet.html
-/// [`union`]: struct.IndexSet.html#method.union
-pub struct Union<'a, T, S> {
-    iter: Chain<Iter<'a, T>, Difference<'a, T, S>>,
-}
-
-impl<'a, T, S> Iterator for Union<'a, T, S>
-where
-    T: Eq + Hash,
-    S: BuildHasher,
-{
-    type Item = &'a T;
-
-    fn next(&mut self) -> Option<Self::Item> {
-        self.iter.next()
-    }
-
-    fn size_hint(&self) -> (usize, Option<usize>) {
-        self.iter.size_hint()
-    }
-
-    fn fold<B, F>(self, init: B, f: F) -> B
-    where
-        F: FnMut(B, Self::Item) -> B,
-    {
-        self.iter.fold(init, f)
-    }
-}
-
-impl<T, S> DoubleEndedIterator for Union<'_, T, S>
-where
-    T: Eq + Hash,
-    S: BuildHasher,
-{
-    fn next_back(&mut self) -> Option<Self::Item> {
-        self.iter.next_back()
-    }
-
-    fn rfold<B, F>(self, init: B, f: F) -> B
-    where
-        F: FnMut(B, Self::Item) -> B,
-    {
-        self.iter.rfold(init, f)
-    }
-}
-
-impl<T, S> FusedIterator for Union<'_, T, S>
-where
-    T: Eq + Hash,
-    S: BuildHasher,
-{
-}
-
-impl<T, S> Clone for Union<'_, T, S> {
-    fn clone(&self) -> Self {
-        Union {
-            iter: self.iter.clone(),
-        }
-    }
-}
-
-impl<T, S> fmt::Debug for Union<'_, T, S>
-where
-    T: fmt::Debug + Eq + Hash,
-    S: BuildHasher,
-{
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        f.debug_list().entries(self.clone()).finish()
-    }
-}
-
 impl<T, S1, S2> BitAnd<&IndexSet<T, S2>> for &IndexSet<T, S1>
 where
     T: Eq + Hash + Clone,
@@ -1383,530 +1167,3 @@ where
         self.difference(other).cloned().collect()
     }
 }
-
-#[cfg(test)]
-mod tests {
-    use super::*;
-    use std::string::String;
-
-    #[test]
-    fn it_works() {
-        let mut set = IndexSet::new();
-        assert_eq!(set.is_empty(), true);
-        set.insert(1);
-        set.insert(1);
-        assert_eq!(set.len(), 1);
-        assert!(set.get(&1).is_some());
-        assert_eq!(set.is_empty(), false);
-    }
-
-    #[test]
-    fn new() {
-        let set = IndexSet::<String>::new();
-        println!("{:?}", set);
-        assert_eq!(set.capacity(), 0);
-        assert_eq!(set.len(), 0);
-        assert_eq!(set.is_empty(), true);
-    }
-
-    #[test]
-    fn insert() {
-        let insert = [0, 4, 2, 12, 8, 7, 11, 5];
-        let not_present = [1, 3, 6, 9, 10];
-        let mut set = IndexSet::with_capacity(insert.len());
-
-        for (i, &elt) in insert.iter().enumerate() {
-            assert_eq!(set.len(), i);
-            set.insert(elt);
-            assert_eq!(set.len(), i + 1);
-            assert_eq!(set.get(&elt), Some(&elt));
-        }
-        println!("{:?}", set);
-
-        for &elt in &not_present {
-            assert!(set.get(&elt).is_none());
-        }
-    }
-
-    #[test]
-    fn insert_full() {
-        let insert = vec![9, 2, 7, 1, 4, 6, 13];
-        let present = vec![1, 6, 2];
-        let mut set = IndexSet::with_capacity(insert.len());
-
-        for (i, &elt) in insert.iter().enumerate() {
-            assert_eq!(set.len(), i);
-            let (index, success) = set.insert_full(elt);
-            assert!(success);
-            assert_eq!(Some(index), set.get_full(&elt).map(|x| x.0));
-            assert_eq!(set.len(), i + 1);
-        }
-
-        let len = set.len();
-        for &elt in &present {
-            let (index, success) = set.insert_full(elt);
-            assert!(!success);
-            assert_eq!(Some(index), set.get_full(&elt).map(|x| x.0));
-            assert_eq!(set.len(), len);
-        }
-    }
-
-    #[test]
-    fn insert_2() {
-        let mut set = IndexSet::with_capacity(16);
-
-        let mut values = vec![];
-        values.extend(0..16);
-        values.extend(if cfg!(miri) { 32..64 } else { 128..267 });
-
-        for &i in &values {
-            let old_set = set.clone();
-            set.insert(i);
-            for value in old_set.iter() {
-                if set.get(value).is_none() {
-                    println!("old_set: {:?}", old_set);
-                    println!("set: {:?}", set);
-                    panic!("did not find {} in set", value);
-                }
-            }
-        }
-
-        for &i in &values {
-            assert!(set.get(&i).is_some(), "did not find {}", i);
-        }
-    }
-
-    #[test]
-    fn insert_dup() {
-        let mut elements = vec![0, 2, 4, 6, 8];
-        let mut set: IndexSet<u8> = elements.drain(..).collect();
-        {
-            let (i, v) = set.get_full(&0).unwrap();
-            assert_eq!(set.len(), 5);
-            assert_eq!(i, 0);
-            assert_eq!(*v, 0);
-        }
-        {
-            let inserted = set.insert(0);
-            let (i, v) = set.get_full(&0).unwrap();
-            assert_eq!(set.len(), 5);
-            assert_eq!(inserted, false);
-            assert_eq!(i, 0);
-            assert_eq!(*v, 0);
-        }
-    }
-
-    #[test]
-    fn insert_order() {
-        let insert = [0, 4, 2, 12, 8, 7, 11, 5, 3, 17, 19, 22, 23];
-        let mut set = IndexSet::new();
-
-        for &elt in &insert {
-            set.insert(elt);
-        }
-
-        assert_eq!(set.iter().count(), set.len());
-        assert_eq!(set.iter().count(), insert.len());
-        for (a, b) in insert.iter().zip(set.iter()) {
-            assert_eq!(a, b);
-        }
-        for (i, v) in (0..insert.len()).zip(set.iter()) {
-            assert_eq!(set.get_index(i).unwrap(), v);
-        }
-    }
-
-    #[test]
-    fn replace() {
-        let replace = [0, 4, 2, 12, 8, 7, 11, 5];
-        let not_present = [1, 3, 6, 9, 10];
-        let mut set = IndexSet::with_capacity(replace.len());
-
-        for (i, &elt) in replace.iter().enumerate() {
-            assert_eq!(set.len(), i);
-            set.replace(elt);
-            assert_eq!(set.len(), i + 1);
-            assert_eq!(set.get(&elt), Some(&elt));
-        }
-        println!("{:?}", set);
-
-        for &elt in &not_present {
-            assert!(set.get(&elt).is_none());
-        }
-    }
-
-    #[test]
-    fn replace_full() {
-        let replace = vec![9, 2, 7, 1, 4, 6, 13];
-        let present = vec![1, 6, 2];
-        let mut set = IndexSet::with_capacity(replace.len());
-
-        for (i, &elt) in replace.iter().enumerate() {
-            assert_eq!(set.len(), i);
-            let (index, replaced) = set.replace_full(elt);
-            assert!(replaced.is_none());
-            assert_eq!(Some(index), set.get_full(&elt).map(|x| x.0));
-            assert_eq!(set.len(), i + 1);
-        }
-
-        let len = set.len();
-        for &elt in &present {
-            let (index, replaced) = set.replace_full(elt);
-            assert_eq!(Some(elt), replaced);
-            assert_eq!(Some(index), set.get_full(&elt).map(|x| x.0));
-            assert_eq!(set.len(), len);
-        }
-    }
-
-    #[test]
-    fn replace_2() {
-        let mut set = IndexSet::with_capacity(16);
-
-        let mut values = vec![];
-        values.extend(0..16);
-        values.extend(if cfg!(miri) { 32..64 } else { 128..267 });
-
-        for &i in &values {
-            let old_set = set.clone();
-            set.replace(i);
-            for value in old_set.iter() {
-                if set.get(value).is_none() {
-                    println!("old_set: {:?}", old_set);
-                    println!("set: {:?}", set);
-                    panic!("did not find {} in set", value);
-                }
-            }
-        }
-
-        for &i in &values {
-            assert!(set.get(&i).is_some(), "did not find {}", i);
-        }
-    }
-
-    #[test]
-    fn replace_dup() {
-        let mut elements = vec![0, 2, 4, 6, 8];
-        let mut set: IndexSet<u8> = elements.drain(..).collect();
-        {
-            let (i, v) = set.get_full(&0).unwrap();
-            assert_eq!(set.len(), 5);
-            assert_eq!(i, 0);
-            assert_eq!(*v, 0);
-        }
-        {
-            let replaced = set.replace(0);
-            let (i, v) = set.get_full(&0).unwrap();
-            assert_eq!(set.len(), 5);
-            assert_eq!(replaced, Some(0));
-            assert_eq!(i, 0);
-            assert_eq!(*v, 0);
-        }
-    }
-
-    #[test]
-    fn replace_order() {
-        let replace = [0, 4, 2, 12, 8, 7, 11, 5, 3, 17, 19, 22, 23];
-        let mut set = IndexSet::new();
-
-        for &elt in &replace {
-            set.replace(elt);
-        }
-
-        assert_eq!(set.iter().count(), set.len());
-        assert_eq!(set.iter().count(), replace.len());
-        for (a, b) in replace.iter().zip(set.iter()) {
-            assert_eq!(a, b);
-        }
-        for (i, v) in (0..replace.len()).zip(set.iter()) {
-            assert_eq!(set.get_index(i).unwrap(), v);
-        }
-    }
-
-    #[test]
-    fn grow() {
-        let insert = [0, 4, 2, 12, 8, 7, 11];
-        let not_present = [1, 3, 6, 9, 10];
-        let mut set = IndexSet::with_capacity(insert.len());
-
-        for (i, &elt) in insert.iter().enumerate() {
-            assert_eq!(set.len(), i);
-            set.insert(elt);
-            assert_eq!(set.len(), i + 1);
-            assert_eq!(set.get(&elt), Some(&elt));
-        }
-
-        println!("{:?}", set);
-        for &elt in &insert {
-            set.insert(elt * 10);
-        }
-        for &elt in &insert {
-            set.insert(elt * 100);
-        }
-        for (i, &elt) in insert.iter().cycle().enumerate().take(100) {
-            set.insert(elt * 100 + i as i32);
-        }
-        println!("{:?}", set);
-        for &elt in &not_present {
-            assert!(set.get(&elt).is_none());
-        }
-    }
-
-    #[test]
-    fn reserve() {
-        let mut set = IndexSet::<usize>::new();
-        assert_eq!(set.capacity(), 0);
-        set.reserve(100);
-        let capacity = set.capacity();
-        assert!(capacity >= 100);
-        for i in 0..capacity {
-            assert_eq!(set.len(), i);
-            set.insert(i);
-            assert_eq!(set.len(), i + 1);
-            assert_eq!(set.capacity(), capacity);
-            assert_eq!(set.get(&i), Some(&i));
-        }
-        set.insert(capacity);
-        assert_eq!(set.len(), capacity + 1);
-        assert!(set.capacity() > capacity);
-        assert_eq!(set.get(&capacity), Some(&capacity));
-    }
-
-    #[test]
-    fn shrink_to_fit() {
-        let mut set = IndexSet::<usize>::new();
-        assert_eq!(set.capacity(), 0);
-        for i in 0..100 {
-            assert_eq!(set.len(), i);
-            set.insert(i);
-            assert_eq!(set.len(), i + 1);
-            assert!(set.capacity() >= i + 1);
-            assert_eq!(set.get(&i), Some(&i));
-            set.shrink_to_fit();
-            assert_eq!(set.len(), i + 1);
-            assert_eq!(set.capacity(), i + 1);
-            assert_eq!(set.get(&i), Some(&i));
-        }
-    }
-
-    #[test]
-    fn remove() {
-        let insert = [0, 4, 2, 12, 8, 7, 11, 5, 3, 17, 19, 22, 23];
-        let mut set = IndexSet::new();
-
-        for &elt in &insert {
-            set.insert(elt);
-        }
-
-        assert_eq!(set.iter().count(), set.len());
-        assert_eq!(set.iter().count(), insert.len());
-        for (a, b) in insert.iter().zip(set.iter()) {
-            assert_eq!(a, b);
-        }
-
-        let remove_fail = [99, 77];
-        let remove = [4, 12, 8, 7];
-
-        for &value in &remove_fail {
-            assert!(set.swap_remove_full(&value).is_none());
-        }
-        println!("{:?}", set);
-        for &value in &remove {
-            //println!("{:?}", set);
-            let index = set.get_full(&value).unwrap().0;
-            assert_eq!(set.swap_remove_full(&value), Some((index, value)));
-        }
-        println!("{:?}", set);
-
-        for value in &insert {
-            assert_eq!(set.get(value).is_some(), !remove.contains(value));
-        }
-        assert_eq!(set.len(), insert.len() - remove.len());
-        assert_eq!(set.iter().count(), insert.len() - remove.len());
-    }
-
-    #[test]
-    fn swap_remove_index() {
-        let insert = [0, 4, 2, 12, 8, 7, 11, 5, 3, 17, 19, 22, 23];
-        let mut set = IndexSet::new();
-
-        for &elt in &insert {
-            set.insert(elt);
-        }
-
-        let mut vector = insert.to_vec();
-        let remove_sequence = &[3, 3, 10, 4, 5, 4, 3, 0, 1];
-
-        // check that the same swap remove sequence on vec and set
-        // have the same result.
-        for &rm in remove_sequence {
-            let out_vec = vector.swap_remove(rm);
-            let out_set = set.swap_remove_index(rm).unwrap();
-            assert_eq!(out_vec, out_set);
-        }
-        assert_eq!(vector.len(), set.len());
-        for (a, b) in vector.iter().zip(set.iter()) {
-            assert_eq!(a, b);
-        }
-    }
-
-    #[test]
-    fn partial_eq_and_eq() {
-        let mut set_a = IndexSet::new();
-        set_a.insert(1);
-        set_a.insert(2);
-        let mut set_b = set_a.clone();
-        assert_eq!(set_a, set_b);
-        set_b.swap_remove(&1);
-        assert_ne!(set_a, set_b);
-
-        let set_c: IndexSet<_> = set_b.into_iter().collect();
-        assert_ne!(set_a, set_c);
-        assert_ne!(set_c, set_a);
-    }
-
-    #[test]
-    fn extend() {
-        let mut set = IndexSet::new();
-        set.extend(vec![&1, &2, &3, &4]);
-        set.extend(vec![5, 6]);
-        assert_eq!(set.into_iter().collect::<Vec<_>>(), vec![1, 2, 3, 4, 5, 6]);
-    }
-
-    #[test]
-    fn comparisons() {
-        let set_a: IndexSet<_> = (0..3).collect();
-        let set_b: IndexSet<_> = (3..6).collect();
-        let set_c: IndexSet<_> = (0..6).collect();
-        let set_d: IndexSet<_> = (3..9).collect();
-
-        assert!(!set_a.is_disjoint(&set_a));
-        assert!(set_a.is_subset(&set_a));
-        assert!(set_a.is_superset(&set_a));
-
-        assert!(set_a.is_disjoint(&set_b));
-        assert!(set_b.is_disjoint(&set_a));
-        assert!(!set_a.is_subset(&set_b));
-        assert!(!set_b.is_subset(&set_a));
-        assert!(!set_a.is_superset(&set_b));
-        assert!(!set_b.is_superset(&set_a));
-
-        assert!(!set_a.is_disjoint(&set_c));
-        assert!(!set_c.is_disjoint(&set_a));
-        assert!(set_a.is_subset(&set_c));
-        assert!(!set_c.is_subset(&set_a));
-        assert!(!set_a.is_superset(&set_c));
-        assert!(set_c.is_superset(&set_a));
-
-        assert!(!set_c.is_disjoint(&set_d));
-        assert!(!set_d.is_disjoint(&set_c));
-        assert!(!set_c.is_subset(&set_d));
-        assert!(!set_d.is_subset(&set_c));
-        assert!(!set_c.is_superset(&set_d));
-        assert!(!set_d.is_superset(&set_c));
-    }
-
-    #[test]
-    fn iter_comparisons() {
-        use std::iter::empty;
-
-        fn check<'a, I1, I2>(iter1: I1, iter2: I2)
-        where
-            I1: Iterator<Item = &'a i32>,
-            I2: Iterator<Item = i32>,
-        {
-            assert!(iter1.copied().eq(iter2));
-        }
-
-        let set_a: IndexSet<_> = (0..3).collect();
-        let set_b: IndexSet<_> = (3..6).collect();
-        let set_c: IndexSet<_> = (0..6).collect();
-        let set_d: IndexSet<_> = (3..9).rev().collect();
-
-        check(set_a.difference(&set_a), empty());
-        check(set_a.symmetric_difference(&set_a), empty());
-        check(set_a.intersection(&set_a), 0..3);
-        check(set_a.union(&set_a), 0..3);
-
-        check(set_a.difference(&set_b), 0..3);
-        check(set_b.difference(&set_a), 3..6);
-        check(set_a.symmetric_difference(&set_b), 0..6);
-        check(set_b.symmetric_difference(&set_a), (3..6).chain(0..3));
-        check(set_a.intersection(&set_b), empty());
-        check(set_b.intersection(&set_a), empty());
-        check(set_a.union(&set_b), 0..6);
-        check(set_b.union(&set_a), (3..6).chain(0..3));
-
-        check(set_a.difference(&set_c), empty());
-        check(set_c.difference(&set_a), 3..6);
-        check(set_a.symmetric_difference(&set_c), 3..6);
-        check(set_c.symmetric_difference(&set_a), 3..6);
-        check(set_a.intersection(&set_c), 0..3);
-        check(set_c.intersection(&set_a), 0..3);
-        check(set_a.union(&set_c), 0..6);
-        check(set_c.union(&set_a), 0..6);
-
-        check(set_c.difference(&set_d), 0..3);
-        check(set_d.difference(&set_c), (6..9).rev());
-        check(
-            set_c.symmetric_difference(&set_d),
-            (0..3).chain((6..9).rev()),
-        );
-        check(set_d.symmetric_difference(&set_c), (6..9).rev().chain(0..3));
-        check(set_c.intersection(&set_d), 3..6);
-        check(set_d.intersection(&set_c), (3..6).rev());
-        check(set_c.union(&set_d), (0..6).chain((6..9).rev()));
-        check(set_d.union(&set_c), (3..9).rev().chain(0..3));
-    }
-
-    #[test]
-    fn ops() {
-        let empty = IndexSet::<i32>::new();
-        let set_a: IndexSet<_> = (0..3).collect();
-        let set_b: IndexSet<_> = (3..6).collect();
-        let set_c: IndexSet<_> = (0..6).collect();
-        let set_d: IndexSet<_> = (3..9).rev().collect();
-
-        #[allow(clippy::eq_op)]
-        {
-            assert_eq!(&set_a & &set_a, set_a);
-            assert_eq!(&set_a | &set_a, set_a);
-            assert_eq!(&set_a ^ &set_a, empty);
-            assert_eq!(&set_a - &set_a, empty);
-        }
-
-        assert_eq!(&set_a & &set_b, empty);
-        assert_eq!(&set_b & &set_a, empty);
-        assert_eq!(&set_a | &set_b, set_c);
-        assert_eq!(&set_b | &set_a, set_c);
-        assert_eq!(&set_a ^ &set_b, set_c);
-        assert_eq!(&set_b ^ &set_a, set_c);
-        assert_eq!(&set_a - &set_b, set_a);
-        assert_eq!(&set_b - &set_a, set_b);
-
-        assert_eq!(&set_a & &set_c, set_a);
-        assert_eq!(&set_c & &set_a, set_a);
-        assert_eq!(&set_a | &set_c, set_c);
-        assert_eq!(&set_c | &set_a, set_c);
-        assert_eq!(&set_a ^ &set_c, set_b);
-        assert_eq!(&set_c ^ &set_a, set_b);
-        assert_eq!(&set_a - &set_c, empty);
-        assert_eq!(&set_c - &set_a, set_b);
-
-        assert_eq!(&set_c & &set_d, set_b);
-        assert_eq!(&set_d & &set_c, set_b);
-        assert_eq!(&set_c | &set_d, &set_a | &set_d);
-        assert_eq!(&set_d | &set_c, &set_a | &set_d);
-        assert_eq!(&set_c ^ &set_d, &set_a | &(&set_d - &set_b));
-        assert_eq!(&set_d ^ &set_c, &set_a | &(&set_d - &set_b));
-        assert_eq!(&set_c - &set_d, set_a);
-        assert_eq!(&set_d - &set_c, &set_d - &set_b);
-    }
-
-    #[test]
-    #[cfg(has_std)]
-    fn from_array() {
-        let set1 = IndexSet::from([1, 2, 3, 4]);
-        let set2: IndexSet<_> = [1, 2, 3, 4].into();
-
-        assert_eq!(set1, set2);
-    }
-}
diff --git a/third_party/rust/indexmap/src/set/iter.rs b/third_party/rust/indexmap/src/set/iter.rs
new file mode 100644
index 0000000000..3f8033c2db
--- /dev/null
+++ b/third_party/rust/indexmap/src/set/iter.rs
@@ -0,0 +1,626 @@
+use super::{Bucket, Entries, IndexSet, Slice};
+
+use alloc::vec::{self, Vec};
+use core::fmt;
+use core::hash::{BuildHasher, Hash};
+use core::iter::{Chain, FusedIterator};
+use core::ops::RangeBounds;
+use core::slice::Iter as SliceIter;
+
+impl<'a, T, S> IntoIterator for &'a IndexSet<T, S> {
+    type Item = &'a T;
+    type IntoIter = Iter<'a, T>;
+
+    fn into_iter(self) -> Self::IntoIter {
+        self.iter()
+    }
+}
+
+impl<T, S> IntoIterator for IndexSet<T, S> {
+    type Item = T;
+    type IntoIter = IntoIter<T>;
+
+    fn into_iter(self) -> Self::IntoIter {
+        IntoIter::new(self.into_entries())
+    }
+}
+
+/// An iterator over the items of an [`IndexSet`].
+///
+/// This `struct` is created by the [`IndexSet::iter`] method.
+/// See its documentation for more.
+pub struct Iter<'a, T> {
+    iter: SliceIter<'a, Bucket<T>>,
+}
+
+impl<'a, T> Iter<'a, T> {
+    pub(super) fn new(entries: &'a [Bucket<T>]) -> Self {
+        Self {
+            iter: entries.iter(),
+        }
+    }
+
+    /// Returns a slice of the remaining entries in the iterator.
+    pub fn as_slice(&self) -> &'a Slice<T> {
+        Slice::from_slice(self.iter.as_slice())
+    }
+}
+
+impl<'a, T> Iterator for Iter<'a, T> {
+    type Item = &'a T;
+
+    iterator_methods!(Bucket::key_ref);
+}
+
+impl<T> DoubleEndedIterator for Iter<'_, T> {
+    double_ended_iterator_methods!(Bucket::key_ref);
+}
+
+impl<T> ExactSizeIterator for Iter<'_, T> {
+    fn len(&self) -> usize {
+        self.iter.len()
+    }
+}
+
+impl<T> FusedIterator for Iter<'_, T> {}
+
+impl<T> Clone for Iter<'_, T> {
+    fn clone(&self) -> Self {
+        Iter {
+            iter: self.iter.clone(),
+        }
+    }
+}
+
+impl<T: fmt::Debug> fmt::Debug for Iter<'_, T> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_list().entries(self.clone()).finish()
+    }
+}
+
+impl<T> Default for Iter<'_, T> {
+    fn default() -> Self {
+        Self { iter: [].iter() }
+    }
+}
+
+/// An owning iterator over the items of an [`IndexSet`].
+///
+/// This `struct` is created by the [`IndexSet::into_iter`] method
+/// (provided by the [`IntoIterator`] trait). See its documentation for more.
+pub struct IntoIter<T> {
+    iter: vec::IntoIter<Bucket<T>>,
+}
+
+impl<T> IntoIter<T> {
+    pub(super) fn new(entries: Vec<Bucket<T>>) -> Self {
+        Self {
+            iter: entries.into_iter(),
+        }
+    }
+
+    /// Returns a slice of the remaining entries in the iterator.
+    pub fn as_slice(&self) -> &Slice<T> {
+        Slice::from_slice(self.iter.as_slice())
+    }
+}
+
+impl<T> Iterator for IntoIter<T> {
+    type Item = T;
+
+    iterator_methods!(Bucket::key);
+}
+
+impl<T> DoubleEndedIterator for IntoIter<T> {
+    double_ended_iterator_methods!(Bucket::key);
+}
+
+impl<T> ExactSizeIterator for IntoIter<T> {
+    fn len(&self) -> usize {
+        self.iter.len()
+    }
+}
+
+impl<T> FusedIterator for IntoIter<T> {}
+
+impl<T: fmt::Debug> fmt::Debug for IntoIter<T> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let iter = self.iter.as_slice().iter().map(Bucket::key_ref);
+        f.debug_list().entries(iter).finish()
+    }
+}
+
+impl<T> Default for IntoIter<T> {
+    fn default() -> Self {
+        Self {
+            iter: Vec::new().into_iter(),
+        }
+    }
+}
+
+/// A draining iterator over the items of an [`IndexSet`].
+///
+/// This `struct` is created by the [`IndexSet::drain`] method.
+/// See its documentation for more.
+pub struct Drain<'a, T> {
+    iter: vec::Drain<'a, Bucket<T>>,
+}
+
+impl<'a, T> Drain<'a, T> {
+    pub(super) fn new(iter: vec::Drain<'a, Bucket<T>>) -> Self {
+        Self { iter }
+    }
+
+    /// Returns a slice of the remaining entries in the iterator.
+    pub fn as_slice(&self) -> &Slice<T> {
+        Slice::from_slice(self.iter.as_slice())
+    }
+}
+
+impl<T> Iterator for Drain<'_, T> {
+    type Item = T;
+
+    iterator_methods!(Bucket::key);
+}
+
+impl<T> DoubleEndedIterator for Drain<'_, T> {
+    double_ended_iterator_methods!(Bucket::key);
+}
+
+impl<T> ExactSizeIterator for Drain<'_, T> {
+    fn len(&self) -> usize {
+        self.iter.len()
+    }
+}
+
+impl<T> FusedIterator for Drain<'_, T> {}
+
+impl<T: fmt::Debug> fmt::Debug for Drain<'_, T> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let iter = self.iter.as_slice().iter().map(Bucket::key_ref);
+        f.debug_list().entries(iter).finish()
+    }
+}
+
+/// A lazy iterator producing elements in the difference of [`IndexSet`]s.
+///
+/// This `struct` is created by the [`IndexSet::difference`] method.
+/// See its documentation for more.
+pub struct Difference<'a, T, S> {
+    iter: Iter<'a, T>,
+    other: &'a IndexSet<T, S>,
+}
+
+impl<'a, T, S> Difference<'a, T, S> {
+    pub(super) fn new<S1>(set: &'a IndexSet<T, S1>, other: &'a IndexSet<T, S>) -> Self {
+        Self {
+            iter: set.iter(),
+            other,
+        }
+    }
+}
+
+impl<'a, T, S> Iterator for Difference<'a, T, S>
+where
+    T: Eq + Hash,
+    S: BuildHasher,
+{
+    type Item = &'a T;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        while let Some(item) = self.iter.next() {
+            if !self.other.contains(item) {
+                return Some(item);
+            }
+        }
+        None
+    }
+
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        (0, self.iter.size_hint().1)
+    }
+}
+
+impl<T, S> DoubleEndedIterator for Difference<'_, T, S>
+where
+    T: Eq + Hash,
+    S: BuildHasher,
+{
+    fn next_back(&mut self) -> Option<Self::Item> {
+        while let Some(item) = self.iter.next_back() {
+            if !self.other.contains(item) {
+                return Some(item);
+            }
+        }
+        None
+    }
+}
+
+impl<T, S> FusedIterator for Difference<'_, T, S>
+where
+    T: Eq + Hash,
+    S: BuildHasher,
+{
+}
+
+impl<T, S> Clone for Difference<'_, T, S> {
+    fn clone(&self) -> Self {
+        Difference {
+            iter: self.iter.clone(),
+            ..*self
+        }
+    }
+}
+
+impl<T, S> fmt::Debug for Difference<'_, T, S>
+where
+    T: fmt::Debug + Eq + Hash,
+    S: BuildHasher,
+{
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_list().entries(self.clone()).finish()
+    }
+}
+
+/// A lazy iterator producing elements in the intersection of [`IndexSet`]s.
+///
+/// This `struct` is created by the [`IndexSet::intersection`] method.
+/// See its documentation for more.
+pub struct Intersection<'a, T, S> {
+    iter: Iter<'a, T>,
+    other: &'a IndexSet<T, S>,
+}
+
+impl<'a, T, S> Intersection<'a, T, S> {
+    pub(super) fn new<S1>(set: &'a IndexSet<T, S1>, other: &'a IndexSet<T, S>) -> Self {
+        Self {
+            iter: set.iter(),
+            other,
+        }
+    }
+}
+
+impl<'a, T, S> Iterator for Intersection<'a, T, S>
+where
+    T: Eq + Hash,
+    S: BuildHasher,
+{
+    type Item = &'a T;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        while let Some(item) = self.iter.next() {
+            if self.other.contains(item) {
+                return Some(item);
+            }
+        }
+        None
+    }
+
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        (0, self.iter.size_hint().1)
+    }
+}
+
+impl<T, S> DoubleEndedIterator for Intersection<'_, T, S>
+where
+    T: Eq + Hash,
+    S: BuildHasher,
+{
+    fn next_back(&mut self) -> Option<Self::Item> {
+        while let Some(item) = self.iter.next_back() {
+            if self.other.contains(item) {
+                return Some(item);
+            }
+        }
+        None
+    }
+}
+
+impl<T, S> FusedIterator for Intersection<'_, T, S>
+where
+    T: Eq + Hash,
+    S: BuildHasher,
+{
+}
+
+impl<T, S> Clone for Intersection<'_, T, S> {
+    fn clone(&self) -> Self {
+        Intersection {
+            iter: self.iter.clone(),
+            ..*self
+        }
+    }
+}
+
+impl<T, S> fmt::Debug for Intersection<'_, T, S>
+where
+    T: fmt::Debug + Eq + Hash,
+    S: BuildHasher,
+{
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_list().entries(self.clone()).finish()
+    }
+}
+
+/// A lazy iterator producing elements in the symmetric difference of [`IndexSet`]s.
+///
+/// This `struct` is created by the [`IndexSet::symmetric_difference`] method.
+/// See its documentation for more.
+pub struct SymmetricDifference<'a, T, S1, S2> {
+    iter: Chain<Difference<'a, T, S2>, Difference<'a, T, S1>>,
+}
+
+impl<'a, T, S1, S2> SymmetricDifference<'a, T, S1, S2>
+where
+    T: Eq + Hash,
+    S1: BuildHasher,
+    S2: BuildHasher,
+{
+    pub(super) fn new(set1: &'a IndexSet<T, S1>, set2: &'a IndexSet<T, S2>) -> Self {
+        let diff1 = set1.difference(set2);
+        let diff2 = set2.difference(set1);
+        Self {
+            iter: diff1.chain(diff2),
+        }
+    }
+}
+
+impl<'a, T, S1, S2> Iterator for SymmetricDifference<'a, T, S1, S2>
+where
+    T: Eq + Hash,
+    S1: BuildHasher,
+    S2: BuildHasher,
+{
+    type Item = &'a T;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        self.iter.next()
+    }
+
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        self.iter.size_hint()
+    }
+
+    fn fold<B, F>(self, init: B, f: F) -> B
+    where
+        F: FnMut(B, Self::Item) -> B,
+    {
+        self.iter.fold(init, f)
+    }
+}
+
+impl<T, S1, S2> DoubleEndedIterator for SymmetricDifference<'_, T, S1, S2>
+where
+    T: Eq + Hash,
+    S1: BuildHasher,
+    S2: BuildHasher,
+{
+    fn next_back(&mut self) -> Option<Self::Item> {
+        self.iter.next_back()
+    }
+
+    fn rfold<B, F>(self, init: B, f: F) -> B
+    where
+        F: FnMut(B, Self::Item) -> B,
+    {
+        self.iter.rfold(init, f)
+    }
+}
+
+impl<T, S1, S2> FusedIterator for SymmetricDifference<'_, T, S1, S2>
+where
+    T: Eq + Hash,
+    S1: BuildHasher,
+    S2: BuildHasher,
+{
+}
+
+impl<T, S1, S2> Clone for SymmetricDifference<'_, T, S1, S2> {
+    fn clone(&self) -> Self {
+        SymmetricDifference {
+            iter: self.iter.clone(),
+        }
+    }
+}
+
+impl<T, S1, S2> fmt::Debug for SymmetricDifference<'_, T, S1, S2>
+where
+    T: fmt::Debug + Eq + Hash,
+    S1: BuildHasher,
+    S2: BuildHasher,
+{
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_list().entries(self.clone()).finish()
+    }
+}
+
+/// A lazy iterator producing elements in the union of [`IndexSet`]s.
+///
+/// This `struct` is created by the [`IndexSet::union`] method.
+/// See its documentation for more.
+pub struct Union<'a, T, S> {
+    iter: Chain<Iter<'a, T>, Difference<'a, T, S>>,
+}
+
+impl<'a, T, S> Union<'a, T, S>
+where
+    T: Eq + Hash,
+    S: BuildHasher,
+{
+    pub(super) fn new<S2>(set1: &'a IndexSet<T, S>, set2: &'a IndexSet<T, S2>) -> Self
+    where
+        S2: BuildHasher,
+    {
+        Self {
+            iter: set1.iter().chain(set2.difference(set1)),
+        }
+    }
+}
+
+impl<'a, T, S> Iterator for Union<'a, T, S>
+where
+    T: Eq + Hash,
+    S: BuildHasher,
+{
+    type Item = &'a T;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        self.iter.next()
+    }
+
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        self.iter.size_hint()
+    }
+
+    fn fold<B, F>(self, init: B, f: F) -> B
+    where
+        F: FnMut(B, Self::Item) -> B,
+    {
+        self.iter.fold(init, f)
+    }
+}
+
+impl<T, S> DoubleEndedIterator for Union<'_, T, S>
+where
+    T: Eq + Hash,
+    S: BuildHasher,
+{
+    fn next_back(&mut self) -> Option<Self::Item> {
+        self.iter.next_back()
+    }
+
+    fn rfold<B, F>(self, init: B, f: F) -> B
+    where
+        F: FnMut(B, Self::Item) -> B,
+    {
+        self.iter.rfold(init, f)
+    }
+}
+
+impl<T, S> FusedIterator for Union<'_, T, S>
+where
+    T: Eq + Hash,
+    S: BuildHasher,
+{
+}
+
+impl<T, S> Clone for Union<'_, T, S> {
+    fn clone(&self) -> Self {
+        Union {
+            iter: self.iter.clone(),
+        }
+    }
+}
+
+impl<T, S> fmt::Debug for Union<'_, T, S>
+where
+    T: fmt::Debug + Eq + Hash,
+    S: BuildHasher,
+{
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_list().entries(self.clone()).finish()
+    }
+}
+
+/// A splicing iterator for `IndexSet`.
+///
+/// This `struct` is created by [`IndexSet::splice()`].
+/// See its documentation for more.
+pub struct Splice<'a, I, T, S>
+where
+    I: Iterator<Item = T>,
+    T: Hash + Eq,
+    S: BuildHasher,
+{
+    iter: crate::map::Splice<'a, UnitValue<I>, T, (), S>,
+}
+
+impl<'a, I, T, S> Splice<'a, I, T, S>
+where
+    I: Iterator<Item = T>,
+    T: Hash + Eq,
+    S: BuildHasher,
+{
+    pub(super) fn new<R>(set: &'a mut IndexSet<T, S>, range: R, replace_with: I) -> Self
+    where
+        R: RangeBounds<usize>,
+    {
+        Self {
+            iter: set.map.splice(range, UnitValue(replace_with)),
+        }
+    }
+}
+
+impl<I, T, S> Iterator for Splice<'_, I, T, S>
+where
+    I: Iterator<Item = T>,
+    T: Hash + Eq,
+    S: BuildHasher,
+{
+    type Item = T;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        Some(self.iter.next()?.0)
+    }
+
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        self.iter.size_hint()
+    }
+}
+
+impl<I, T, S> DoubleEndedIterator for Splice<'_, I, T, S>
+where
+    I: Iterator<Item = T>,
+    T: Hash + Eq,
+    S: BuildHasher,
+{
+    fn next_back(&mut self) -> Option<Self::Item> {
+        Some(self.iter.next_back()?.0)
+    }
+}
+
+impl<I, T, S> ExactSizeIterator for Splice<'_, I, T, S>
+where
+    I: Iterator<Item = T>,
+    T: Hash + Eq,
+    S: BuildHasher,
+{
+    fn len(&self) -> usize {
+        self.iter.len()
+    }
+}
+
+impl<I, T, S> FusedIterator for Splice<'_, I, T, S>
+where
+    I: Iterator<Item = T>,
+    T: Hash + Eq,
+    S: BuildHasher,
+{
+}
+
+struct UnitValue<I>(I);
+
+impl<I: Iterator> Iterator for UnitValue<I> {
+    type Item = (I::Item, ());
+
+    fn next(&mut self) -> Option<Self::Item> {
+        self.0.next().map(|x| (x, ()))
+    }
+}
+
+impl<'a, I, T, S> fmt::Debug for Splice<'a, I, T, S>
+where
+    I: fmt::Debug + Iterator<Item = T>,
+    T: fmt::Debug + Hash + Eq,
+    S: BuildHasher,
+{
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        fmt::Debug::fmt(&self.iter, f)
+    }
+}
+
+impl<I: fmt::Debug> fmt::Debug for UnitValue<I> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        fmt::Debug::fmt(&self.0, f)
+    }
+}
diff --git a/third_party/rust/indexmap/src/set/mutable.rs b/third_party/rust/indexmap/src/set/mutable.rs
new file mode 100644
index 0000000000..20eaa11221
--- /dev/null
+++ b/third_party/rust/indexmap/src/set/mutable.rs
@@ -0,0 +1,86 @@
+use core::hash::{BuildHasher, Hash};
+
+use super::{Equivalent, IndexSet};
+use crate::map::MutableKeys;
+
+/// Opt-in mutable access to [`IndexSet`] values.
+///
+/// These methods expose `&mut T`, mutable references to the value as it is stored
+/// in the set.
+/// You are allowed to modify the values in the set **if the modification
+/// does not change the value’s hash and equality**.
+///
+/// If values are modified erroneously, you can no longer look them up.
+/// This is sound (memory safe) but a logical error hazard (just like
+/// implementing `PartialEq`, `Eq`, or `Hash` incorrectly would be).
+///
+/// `use` this trait to enable its methods for `IndexSet`.
+///
+/// This trait is sealed and cannot be implemented for types outside this crate.
+pub trait MutableValues: private::Sealed {
+    type Value;
+
+    /// Return item index and mutable reference to the value
+    ///
+    /// Computes in **O(1)** time (average).
+    fn get_full_mut2<Q>(&mut self, value: &Q) -> Option<(usize, &mut Self::Value)>
+    where
+        Q: ?Sized + Hash + Equivalent<Self::Value>;
+
+    /// Return mutable reference to the value at an index.
+    ///
+    /// Valid indices are *0 <= index < self.len()*
+    ///
+    /// Computes in **O(1)** time.
+    fn get_index_mut2(&mut self, index: usize) -> Option<&mut Self::Value>;
+
+    /// Scan through each value in the set and keep those where the
+    /// closure `keep` returns `true`.
+    ///
+    /// The values are visited in order, and remaining values keep their order.
+    ///
+    /// Computes in **O(n)** time (average).
+    fn retain2<F>(&mut self, keep: F)
+    where
+        F: FnMut(&mut Self::Value) -> bool;
+}
+
+/// Opt-in mutable access to [`IndexSet`] values.
+///
+/// See [`MutableValues`] for more information.
+impl<T, S> MutableValues for IndexSet<T, S>
+where
+    S: BuildHasher,
+{
+    type Value = T;
+
+    fn get_full_mut2<Q>(&mut self, value: &Q) -> Option<(usize, &mut T)>
+    where
+        Q: ?Sized + Hash + Equivalent<T>,
+    {
+        match self.map.get_full_mut2(value) {
+            Some((index, value, ())) => Some((index, value)),
+            None => None,
+        }
+    }
+
+    fn get_index_mut2(&mut self, index: usize) -> Option<&mut T> {
+        match self.map.get_index_mut2(index) {
+            Some((value, ())) => Some(value),
+            None => None,
+        }
+    }
+
+    fn retain2<F>(&mut self, mut keep: F)
+    where
+        F: FnMut(&mut T) -> bool,
+    {
+        self.map.retain2(move |value, ()| keep(value));
+    }
+}
+
+mod private {
+    pub trait Sealed {}
+
+    impl<T, S> Sealed for super::IndexSet<T, S> {}
+}
diff --git a/third_party/rust/indexmap/src/set/slice.rs b/third_party/rust/indexmap/src/set/slice.rs
new file mode 100644
index 0000000000..9fc208c706
--- /dev/null
+++ b/third_party/rust/indexmap/src/set/slice.rs
@@ -0,0 +1,340 @@
+use super::{Bucket, Entries, IndexSet, IntoIter, Iter};
+use crate::util::try_simplify_range;
+
+use alloc::boxed::Box;
+use alloc::vec::Vec;
+use core::cmp::Ordering;
+use core::fmt;
+use core::hash::{Hash, Hasher};
+use core::ops::{self, Bound, Index, RangeBounds};
+
+/// A dynamically-sized slice of values in an [`IndexSet`].
+///
+/// This supports indexed operations much like a `[T]` slice,
+/// but not any hashed operations on the values.
+///
+/// Unlike `IndexSet`, `Slice` does consider the order for [`PartialEq`]
+/// and [`Eq`], and it also implements [`PartialOrd`], [`Ord`], and [`Hash`].
+#[repr(transparent)]
+pub struct Slice<T> {
+    pub(crate) entries: [Bucket<T>],
+}
+
+// SAFETY: `Slice<T>` is a transparent wrapper around `[Bucket<T>]`,
+// and reference lifetimes are bound together in function signatures.
+#[allow(unsafe_code)]
+impl<T> Slice<T> {
+    pub(super) const fn from_slice(entries: &[Bucket<T>]) -> &Self {
+        unsafe { &*(entries as *const [Bucket<T>] as *const Self) }
+    }
+
+    pub(super) fn from_boxed(entries: Box<[Bucket<T>]>) -> Box<Self> {
+        unsafe { Box::from_raw(Box::into_raw(entries) as *mut Self) }
+    }
+
+    fn into_boxed(self: Box<Self>) -> Box<[Bucket<T>]> {
+        unsafe { Box::from_raw(Box::into_raw(self) as *mut [Bucket<T>]) }
+    }
+}
+
+impl<T> Slice<T> {
+    pub(crate) fn into_entries(self: Box<Self>) -> Vec<Bucket<T>> {
+        self.into_boxed().into_vec()
+    }
+
+    /// Returns an empty slice.
+    pub const fn new<'a>() -> &'a Self {
+        Self::from_slice(&[])
+    }
+
+    /// Return the number of elements in the set slice.
+    pub const fn len(&self) -> usize {
+        self.entries.len()
+    }
+
+    /// Returns true if the set slice contains no elements.
+    pub const fn is_empty(&self) -> bool {
+        self.entries.is_empty()
+    }
+
+    /// Get a value by index.
+    ///
+    /// Valid indices are *0 <= index < self.len()*
+    pub fn get_index(&self, index: usize) -> Option<&T> {
+        self.entries.get(index).map(Bucket::key_ref)
+    }
+
+    /// Returns a slice of values in the given range of indices.
+    ///
+    /// Valid indices are *0 <= index < self.len()*
+    pub fn get_range<R: RangeBounds<usize>>(&self, range: R) -> Option<&Self> {
+        let range = try_simplify_range(range, self.entries.len())?;
+        self.entries.get(range).map(Self::from_slice)
+    }
+
+    /// Get the first value.
+    pub fn first(&self) -> Option<&T> {
+        self.entries.first().map(Bucket::key_ref)
+    }
+
+    /// Get the last value.
+    pub fn last(&self) -> Option<&T> {
+        self.entries.last().map(Bucket::key_ref)
+    }
+
+    /// Divides one slice into two at an index.
+    ///
+    /// ***Panics*** if `index > len`.
+    pub fn split_at(&self, index: usize) -> (&Self, &Self) {
+        let (first, second) = self.entries.split_at(index);
+        (Self::from_slice(first), Self::from_slice(second))
+    }
+
+    /// Returns the first value and the rest of the slice,
+    /// or `None` if it is empty.
+    pub fn split_first(&self) -> Option<(&T, &Self)> {
+        if let [first, rest @ ..] = &self.entries {
+            Some((&first.key, Self::from_slice(rest)))
+        } else {
+            None
+        }
+    }
+
+    /// Returns the last value and the rest of the slice,
+    /// or `None` if it is empty.
+    pub fn split_last(&self) -> Option<(&T, &Self)> {
+        if let [rest @ .., last] = &self.entries {
+            Some((&last.key, Self::from_slice(rest)))
+        } else {
+            None
+        }
+    }
+
+    /// Return an iterator over the values of the set slice.
+    pub fn iter(&self) -> Iter<'_, T> {
+        Iter::new(&self.entries)
+    }
+
+    /// Search over a sorted set for a value.
+    ///
+    /// Returns the position where that value is present, or the position where it can be inserted
+    /// to maintain the sort. See [`slice::binary_search`] for more details.
+    ///
+    /// Computes in **O(log(n))** time, which is notably less scalable than looking the value up in
+    /// the set this is a slice from using [`IndexSet::get_index_of`], but this can also position
+    /// missing values.
+    pub fn binary_search(&self, x: &T) -> Result<usize, usize>
+    where
+        T: Ord,
+    {
+        self.binary_search_by(|p| p.cmp(x))
+    }
+
+    /// Search over a sorted set with a comparator function.
+    ///
+    /// Returns the position where that value is present, or the position where it can be inserted
+    /// to maintain the sort. See [`slice::binary_search_by`] for more details.
+    ///
+    /// Computes in **O(log(n))** time.
+    #[inline]
+    pub fn binary_search_by<'a, F>(&'a self, mut f: F) -> Result<usize, usize>
+    where
+        F: FnMut(&'a T) -> Ordering,
+    {
+        self.entries.binary_search_by(move |a| f(&a.key))
+    }
+
+    /// Search over a sorted set with an extraction function.
+    ///
+    /// Returns the position where that value is present, or the position where it can be inserted
+    /// to maintain the sort. See [`slice::binary_search_by_key`] for more details.
+    ///
+    /// Computes in **O(log(n))** time.
+    #[inline]
+    pub fn binary_search_by_key<'a, B, F>(&'a self, b: &B, mut f: F) -> Result<usize, usize>
+    where
+        F: FnMut(&'a T) -> B,
+        B: Ord,
+    {
+        self.binary_search_by(|k| f(k).cmp(b))
+    }
+
+    /// Returns the index of the partition point of a sorted set according to the given predicate
+    /// (the index of the first element of the second partition).
+    ///
+    /// See [`slice::partition_point`] for more details.
+    ///
+    /// Computes in **O(log(n))** time.
+    #[must_use]
+    pub fn partition_point<P>(&self, mut pred: P) -> usize
+    where
+        P: FnMut(&T) -> bool,
+    {
+        self.entries.partition_point(move |a| pred(&a.key))
+    }
+}
+
+impl<'a, T> IntoIterator for &'a Slice<T> {
+    type IntoIter = Iter<'a, T>;
+    type Item = &'a T;
+
+    fn into_iter(self) -> Self::IntoIter {
+        self.iter()
+    }
+}
+
+impl<T> IntoIterator for Box<Slice<T>> {
+    type IntoIter = IntoIter<T>;
+    type Item = T;
+
+    fn into_iter(self) -> Self::IntoIter {
+        IntoIter::new(self.into_entries())
+    }
+}
+
+impl<T> Default for &'_ Slice<T> {
+    fn default() -> Self {
+        Slice::from_slice(&[])
+    }
+}
+
+impl<T> Default for Box<Slice<T>> {
+    fn default() -> Self {
+        Slice::from_boxed(Box::default())
+    }
+}
+
+impl<T: Clone> Clone for Box<Slice<T>> {
+    fn clone(&self) -> Self {
+        Slice::from_boxed(self.entries.to_vec().into_boxed_slice())
+    }
+}
+
+impl<T: Copy> From<&Slice<T>> for Box<Slice<T>> {
+    fn from(slice: &Slice<T>) -> Self {
+        Slice::from_boxed(Box::from(&slice.entries))
+    }
+}
+
+impl<T: fmt::Debug> fmt::Debug for Slice<T> {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_list().entries(self).finish()
+    }
+}
+
+impl<T: PartialEq> PartialEq for Slice<T> {
+    fn eq(&self, other: &Self) -> bool {
+        self.len() == other.len() && self.iter().eq(other)
+    }
+}
+
+impl<T: Eq> Eq for Slice<T> {}
+
+impl<T: PartialOrd> PartialOrd for Slice<T> {
+    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {
+        self.iter().partial_cmp(other)
+    }
+}
+
+impl<T: Ord> Ord for Slice<T> {
+    fn cmp(&self, other: &Self) -> Ordering {
+        self.iter().cmp(other)
+    }
+}
+
+impl<T: Hash> Hash for Slice<T> {
+    fn hash<H: Hasher>(&self, state: &mut H) {
+        self.len().hash(state);
+        for value in self {
+            value.hash(state);
+        }
+    }
+}
+
+impl<T> Index<usize> for Slice<T> {
+    type Output = T;
+
+    fn index(&self, index: usize) -> &Self::Output {
+        &self.entries[index].key
+    }
+}
+
+// We can't have `impl<I: RangeBounds<usize>> Index<I>` because that conflicts with `Index<usize>`.
+// Instead, we repeat the implementations for all the core range types.
+macro_rules! impl_index {
+    ($($range:ty),*) => {$(
+        impl<T, S> Index<$range> for IndexSet<T, S> {
+            type Output = Slice<T>;
+
+            fn index(&self, range: $range) -> &Self::Output {
+                Slice::from_slice(&self.as_entries()[range])
+            }
+        }
+
+        impl<T> Index<$range> for Slice<T> {
+            type Output = Self;
+
+            fn index(&self, range: $range) -> &Self::Output {
+                Slice::from_slice(&self.entries[range])
+            }
+        }
+    )*}
+}
+impl_index!(
+    ops::Range<usize>,
+    ops::RangeFrom<usize>,
+    ops::RangeFull,
+    ops::RangeInclusive<usize>,
+    ops::RangeTo<usize>,
+    ops::RangeToInclusive<usize>,
+    (Bound<usize>, Bound<usize>)
+);
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn slice_index() {
+        fn check(vec_slice: &[i32], set_slice: &Slice<i32>, sub_slice: &Slice<i32>) {
+            assert_eq!(set_slice as *const _, sub_slice as *const _);
+            itertools::assert_equal(vec_slice, set_slice);
+        }
+
+        let vec: Vec<i32> = (0..10).map(|i| i * i).collect();
+        let set: IndexSet<i32> = vec.iter().cloned().collect();
+        let slice = set.as_slice();
+
+        // RangeFull
+        check(&vec[..], &set[..], &slice[..]);
+
+        for i in 0usize..10 {
+            // Index
+            assert_eq!(vec[i], set[i]);
+            assert_eq!(vec[i], slice[i]);
+
+            // RangeFrom
+            check(&vec[i..], &set[i..], &slice[i..]);
+
+            // RangeTo
+            check(&vec[..i], &set[..i], &slice[..i]);
+
+            // RangeToInclusive
+            check(&vec[..=i], &set[..=i], &slice[..=i]);
+
+            // (Bound<usize>, Bound<usize>)
+            let bounds = (Bound::Excluded(i), Bound::Unbounded);
+            check(&vec[i + 1..], &set[bounds], &slice[bounds]);
+
+            for j in i..=10 {
+                // Range
+                check(&vec[i..j], &set[i..j], &slice[i..j]);
+            }
+
+            for j in i..10 {
+                // RangeInclusive
+                check(&vec[i..=j], &set[i..=j], &slice[i..=j]);
+            }
+        }
+    }
+}
diff --git a/third_party/rust/indexmap/src/set/tests.rs b/third_party/rust/indexmap/src/set/tests.rs
new file mode 100644
index 0000000000..35a076e8de
--- /dev/null
+++ b/third_party/rust/indexmap/src/set/tests.rs
@@ -0,0 +1,723 @@
+use super::*;
+use std::string::String;
+
+#[test]
+fn it_works() {
+    let mut set = IndexSet::new();
+    assert_eq!(set.is_empty(), true);
+    set.insert(1);
+    set.insert(1);
+    assert_eq!(set.len(), 1);
+    assert!(set.get(&1).is_some());
+    assert_eq!(set.is_empty(), false);
+}
+
+#[test]
+fn new() {
+    let set = IndexSet::<String>::new();
+    println!("{:?}", set);
+    assert_eq!(set.capacity(), 0);
+    assert_eq!(set.len(), 0);
+    assert_eq!(set.is_empty(), true);
+}
+
+#[test]
+fn insert() {
+    let insert = [0, 4, 2, 12, 8, 7, 11, 5];
+    let not_present = [1, 3, 6, 9, 10];
+    let mut set = IndexSet::with_capacity(insert.len());
+
+    for (i, &elt) in insert.iter().enumerate() {
+        assert_eq!(set.len(), i);
+        set.insert(elt);
+        assert_eq!(set.len(), i + 1);
+        assert_eq!(set.get(&elt), Some(&elt));
+    }
+    println!("{:?}", set);
+
+    for &elt in &not_present {
+        assert!(set.get(&elt).is_none());
+    }
+}
+
+#[test]
+fn insert_full() {
+    let insert = vec![9, 2, 7, 1, 4, 6, 13];
+    let present = vec![1, 6, 2];
+    let mut set = IndexSet::with_capacity(insert.len());
+
+    for (i, &elt) in insert.iter().enumerate() {
+        assert_eq!(set.len(), i);
+        let (index, success) = set.insert_full(elt);
+        assert!(success);
+        assert_eq!(Some(index), set.get_full(&elt).map(|x| x.0));
+        assert_eq!(set.len(), i + 1);
+    }
+
+    let len = set.len();
+    for &elt in &present {
+        let (index, success) = set.insert_full(elt);
+        assert!(!success);
+        assert_eq!(Some(index), set.get_full(&elt).map(|x| x.0));
+        assert_eq!(set.len(), len);
+    }
+}
+
+#[test]
+fn insert_2() {
+    let mut set = IndexSet::with_capacity(16);
+
+    let mut values = vec![];
+    values.extend(0..16);
+    values.extend(if cfg!(miri) { 32..64 } else { 128..267 });
+
+    for &i in &values {
+        let old_set = set.clone();
+        set.insert(i);
+        for value in old_set.iter() {
+            if set.get(value).is_none() {
+                println!("old_set: {:?}", old_set);
+                println!("set: {:?}", set);
+                panic!("did not find {} in set", value);
+            }
+        }
+    }
+
+    for &i in &values {
+        assert!(set.get(&i).is_some(), "did not find {}", i);
+    }
+}
+
+#[test]
+fn insert_dup() {
+    let mut elements = vec![0, 2, 4, 6, 8];
+    let mut set: IndexSet<u8> = elements.drain(..).collect();
+    {
+        let (i, v) = set.get_full(&0).unwrap();
+        assert_eq!(set.len(), 5);
+        assert_eq!(i, 0);
+        assert_eq!(*v, 0);
+    }
+    {
+        let inserted = set.insert(0);
+        let (i, v) = set.get_full(&0).unwrap();
+        assert_eq!(set.len(), 5);
+        assert_eq!(inserted, false);
+        assert_eq!(i, 0);
+        assert_eq!(*v, 0);
+    }
+}
+
+#[test]
+fn insert_order() {
+    let insert = [0, 4, 2, 12, 8, 7, 11, 5, 3, 17, 19, 22, 23];
+    let mut set = IndexSet::new();
+
+    for &elt in &insert {
+        set.insert(elt);
+    }
+
+    assert_eq!(set.iter().count(), set.len());
+    assert_eq!(set.iter().count(), insert.len());
+    for (a, b) in insert.iter().zip(set.iter()) {
+        assert_eq!(a, b);
+    }
+    for (i, v) in (0..insert.len()).zip(set.iter()) {
+        assert_eq!(set.get_index(i).unwrap(), v);
+    }
+}
+
+#[test]
+fn shift_insert() {
+    let insert = [0, 4, 2, 12, 8, 7, 11, 5, 3, 17, 19, 22, 23];
+    let mut set = IndexSet::new();
+
+    for &elt in &insert {
+        set.shift_insert(0, elt);
+    }
+
+    assert_eq!(set.iter().count(), set.len());
+    assert_eq!(set.iter().count(), insert.len());
+    for (a, b) in insert.iter().rev().zip(set.iter()) {
+        assert_eq!(a, b);
+    }
+    for (i, v) in (0..insert.len()).zip(set.iter()) {
+        assert_eq!(set.get_index(i).unwrap(), v);
+    }
+
+    // "insert" that moves an existing entry
+    set.shift_insert(0, insert[0]);
+    assert_eq!(set.iter().count(), insert.len());
+    assert_eq!(insert[0], set[0]);
+    for (a, b) in insert[1..].iter().rev().zip(set.iter().skip(1)) {
+        assert_eq!(a, b);
+    }
+}
+
+#[test]
+fn replace() {
+    let replace = [0, 4, 2, 12, 8, 7, 11, 5];
+    let not_present = [1, 3, 6, 9, 10];
+    let mut set = IndexSet::with_capacity(replace.len());
+
+    for (i, &elt) in replace.iter().enumerate() {
+        assert_eq!(set.len(), i);
+        set.replace(elt);
+        assert_eq!(set.len(), i + 1);
+        assert_eq!(set.get(&elt), Some(&elt));
+    }
+    println!("{:?}", set);
+
+    for &elt in &not_present {
+        assert!(set.get(&elt).is_none());
+    }
+}
+
+#[test]
+fn replace_full() {
+    let replace = vec![9, 2, 7, 1, 4, 6, 13];
+    let present = vec![1, 6, 2];
+    let mut set = IndexSet::with_capacity(replace.len());
+
+    for (i, &elt) in replace.iter().enumerate() {
+        assert_eq!(set.len(), i);
+        let (index, replaced) = set.replace_full(elt);
+        assert!(replaced.is_none());
+        assert_eq!(Some(index), set.get_full(&elt).map(|x| x.0));
+        assert_eq!(set.len(), i + 1);
+    }
+
+    let len = set.len();
+    for &elt in &present {
+        let (index, replaced) = set.replace_full(elt);
+        assert_eq!(Some(elt), replaced);
+        assert_eq!(Some(index), set.get_full(&elt).map(|x| x.0));
+        assert_eq!(set.len(), len);
+    }
+}
+
+#[test]
+fn replace_2() {
+    let mut set = IndexSet::with_capacity(16);
+
+    let mut values = vec![];
+    values.extend(0..16);
+    values.extend(if cfg!(miri) { 32..64 } else { 128..267 });
+
+    for &i in &values {
+        let old_set = set.clone();
+        set.replace(i);
+        for value in old_set.iter() {
+            if set.get(value).is_none() {
+                println!("old_set: {:?}", old_set);
+                println!("set: {:?}", set);
+                panic!("did not find {} in set", value);
+            }
+        }
+    }
+
+    for &i in &values {
+        assert!(set.get(&i).is_some(), "did not find {}", i);
+    }
+}
+
+#[test]
+fn replace_dup() {
+    let mut elements = vec![0, 2, 4, 6, 8];
+    let mut set: IndexSet<u8> = elements.drain(..).collect();
+    {
+        let (i, v) = set.get_full(&0).unwrap();
+        assert_eq!(set.len(), 5);
+        assert_eq!(i, 0);
+        assert_eq!(*v, 0);
+    }
+    {
+        let replaced = set.replace(0);
+        let (i, v) = set.get_full(&0).unwrap();
+        assert_eq!(set.len(), 5);
+        assert_eq!(replaced, Some(0));
+        assert_eq!(i, 0);
+        assert_eq!(*v, 0);
+    }
+}
+
+#[test]
+fn replace_order() {
+    let replace = [0, 4, 2, 12, 8, 7, 11, 5, 3, 17, 19, 22, 23];
+    let mut set = IndexSet::new();
+
+    for &elt in &replace {
+        set.replace(elt);
+    }
+
+    assert_eq!(set.iter().count(), set.len());
+    assert_eq!(set.iter().count(), replace.len());
+    for (a, b) in replace.iter().zip(set.iter()) {
+        assert_eq!(a, b);
+    }
+    for (i, v) in (0..replace.len()).zip(set.iter()) {
+        assert_eq!(set.get_index(i).unwrap(), v);
+    }
+}
+
+#[test]
+fn replace_change() {
+    // Check pointers to make sure it really changes
+    let mut set = indexset!(vec![42]);
+    let old_ptr = set[0].as_ptr();
+    let new = set[0].clone();
+    let new_ptr = new.as_ptr();
+    assert_ne!(old_ptr, new_ptr);
+    let replaced = set.replace(new).unwrap();
+    assert_eq!(replaced.as_ptr(), old_ptr);
+}
+
+#[test]
+fn grow() {
+    let insert = [0, 4, 2, 12, 8, 7, 11];
+    let not_present = [1, 3, 6, 9, 10];
+    let mut set = IndexSet::with_capacity(insert.len());
+
+    for (i, &elt) in insert.iter().enumerate() {
+        assert_eq!(set.len(), i);
+        set.insert(elt);
+        assert_eq!(set.len(), i + 1);
+        assert_eq!(set.get(&elt), Some(&elt));
+    }
+
+    println!("{:?}", set);
+    for &elt in &insert {
+        set.insert(elt * 10);
+    }
+    for &elt in &insert {
+        set.insert(elt * 100);
+    }
+    for (i, &elt) in insert.iter().cycle().enumerate().take(100) {
+        set.insert(elt * 100 + i as i32);
+    }
+    println!("{:?}", set);
+    for &elt in &not_present {
+        assert!(set.get(&elt).is_none());
+    }
+}
+
+#[test]
+fn reserve() {
+    let mut set = IndexSet::<usize>::new();
+    assert_eq!(set.capacity(), 0);
+    set.reserve(100);
+    let capacity = set.capacity();
+    assert!(capacity >= 100);
+    for i in 0..capacity {
+        assert_eq!(set.len(), i);
+        set.insert(i);
+        assert_eq!(set.len(), i + 1);
+        assert_eq!(set.capacity(), capacity);
+        assert_eq!(set.get(&i), Some(&i));
+    }
+    set.insert(capacity);
+    assert_eq!(set.len(), capacity + 1);
+    assert!(set.capacity() > capacity);
+    assert_eq!(set.get(&capacity), Some(&capacity));
+}
+
+#[test]
+fn try_reserve() {
+    let mut set = IndexSet::<usize>::new();
+    assert_eq!(set.capacity(), 0);
+    assert_eq!(set.try_reserve(100), Ok(()));
+    assert!(set.capacity() >= 100);
+    assert!(set.try_reserve(usize::MAX).is_err());
+}
+
+#[test]
+fn shrink_to_fit() {
+    let mut set = IndexSet::<usize>::new();
+    assert_eq!(set.capacity(), 0);
+    for i in 0..100 {
+        assert_eq!(set.len(), i);
+        set.insert(i);
+        assert_eq!(set.len(), i + 1);
+        assert!(set.capacity() >= i + 1);
+        assert_eq!(set.get(&i), Some(&i));
+        set.shrink_to_fit();
+        assert_eq!(set.len(), i + 1);
+        assert_eq!(set.capacity(), i + 1);
+        assert_eq!(set.get(&i), Some(&i));
+    }
+}
+
+#[test]
+fn remove() {
+    let insert = [0, 4, 2, 12, 8, 7, 11, 5, 3, 17, 19, 22, 23];
+    let mut set = IndexSet::new();
+
+    for &elt in &insert {
+        set.insert(elt);
+    }
+
+    assert_eq!(set.iter().count(), set.len());
+    assert_eq!(set.iter().count(), insert.len());
+    for (a, b) in insert.iter().zip(set.iter()) {
+        assert_eq!(a, b);
+    }
+
+    let remove_fail = [99, 77];
+    let remove = [4, 12, 8, 7];
+
+    for &value in &remove_fail {
+        assert!(set.swap_remove_full(&value).is_none());
+    }
+    println!("{:?}", set);
+    for &value in &remove {
+        //println!("{:?}", set);
+        let index = set.get_full(&value).unwrap().0;
+        assert_eq!(set.swap_remove_full(&value), Some((index, value)));
+    }
+    println!("{:?}", set);
+
+    for value in &insert {
+        assert_eq!(set.get(value).is_some(), !remove.contains(value));
+    }
+    assert_eq!(set.len(), insert.len() - remove.len());
+    assert_eq!(set.iter().count(), insert.len() - remove.len());
+}
+
+#[test]
+fn swap_remove_index() {
+    let insert = [0, 4, 2, 12, 8, 7, 11, 5, 3, 17, 19, 22, 23];
+    let mut set = IndexSet::new();
+
+    for &elt in &insert {
+        set.insert(elt);
+    }
+
+    let mut vector = insert.to_vec();
+    let remove_sequence = &[3, 3, 10, 4, 5, 4, 3, 0, 1];
+
+    // check that the same swap remove sequence on vec and set
+    // have the same result.
+    for &rm in remove_sequence {
+        let out_vec = vector.swap_remove(rm);
+        let out_set = set.swap_remove_index(rm).unwrap();
+        assert_eq!(out_vec, out_set);
+    }
+    assert_eq!(vector.len(), set.len());
+    for (a, b) in vector.iter().zip(set.iter()) {
+        assert_eq!(a, b);
+    }
+}
+
+#[test]
+fn partial_eq_and_eq() {
+    let mut set_a = IndexSet::new();
+    set_a.insert(1);
+    set_a.insert(2);
+    let mut set_b = set_a.clone();
+    assert_eq!(set_a, set_b);
+    set_b.swap_remove(&1);
+    assert_ne!(set_a, set_b);
+
+    let set_c: IndexSet<_> = set_b.into_iter().collect();
+    assert_ne!(set_a, set_c);
+    assert_ne!(set_c, set_a);
+}
+
+#[test]
+fn extend() {
+    let mut set = IndexSet::new();
+    set.extend(vec![&1, &2, &3, &4]);
+    set.extend(vec![5, 6]);
+    assert_eq!(set.into_iter().collect::<Vec<_>>(), vec![1, 2, 3, 4, 5, 6]);
+}
+
+#[test]
+fn comparisons() {
+    let set_a: IndexSet<_> = (0..3).collect();
+    let set_b: IndexSet<_> = (3..6).collect();
+    let set_c: IndexSet<_> = (0..6).collect();
+    let set_d: IndexSet<_> = (3..9).collect();
+
+    assert!(!set_a.is_disjoint(&set_a));
+    assert!(set_a.is_subset(&set_a));
+    assert!(set_a.is_superset(&set_a));
+
+    assert!(set_a.is_disjoint(&set_b));
+    assert!(set_b.is_disjoint(&set_a));
+    assert!(!set_a.is_subset(&set_b));
+    assert!(!set_b.is_subset(&set_a));
+    assert!(!set_a.is_superset(&set_b));
+    assert!(!set_b.is_superset(&set_a));
+
+    assert!(!set_a.is_disjoint(&set_c));
+    assert!(!set_c.is_disjoint(&set_a));
+    assert!(set_a.is_subset(&set_c));
+    assert!(!set_c.is_subset(&set_a));
+    assert!(!set_a.is_superset(&set_c));
+    assert!(set_c.is_superset(&set_a));
+
+    assert!(!set_c.is_disjoint(&set_d));
+    assert!(!set_d.is_disjoint(&set_c));
+    assert!(!set_c.is_subset(&set_d));
+    assert!(!set_d.is_subset(&set_c));
+    assert!(!set_c.is_superset(&set_d));
+    assert!(!set_d.is_superset(&set_c));
+}
+
+#[test]
+fn iter_comparisons() {
+    use std::iter::empty;
+
+    fn check<'a, I1, I2>(iter1: I1, iter2: I2)
+    where
+        I1: Iterator<Item = &'a i32>,
+        I2: Iterator<Item = i32>,
+    {
+        assert!(iter1.copied().eq(iter2));
+    }
+
+    let set_a: IndexSet<_> = (0..3).collect();
+    let set_b: IndexSet<_> = (3..6).collect();
+    let set_c: IndexSet<_> = (0..6).collect();
+    let set_d: IndexSet<_> = (3..9).rev().collect();
+
+    check(set_a.difference(&set_a), empty());
+    check(set_a.symmetric_difference(&set_a), empty());
+    check(set_a.intersection(&set_a), 0..3);
+    check(set_a.union(&set_a), 0..3);
+
+    check(set_a.difference(&set_b), 0..3);
+    check(set_b.difference(&set_a), 3..6);
+    check(set_a.symmetric_difference(&set_b), 0..6);
+    check(set_b.symmetric_difference(&set_a), (3..6).chain(0..3));
+    check(set_a.intersection(&set_b), empty());
+    check(set_b.intersection(&set_a), empty());
+    check(set_a.union(&set_b), 0..6);
+    check(set_b.union(&set_a), (3..6).chain(0..3));
+
+    check(set_a.difference(&set_c), empty());
+    check(set_c.difference(&set_a), 3..6);
+    check(set_a.symmetric_difference(&set_c), 3..6);
+    check(set_c.symmetric_difference(&set_a), 3..6);
+    check(set_a.intersection(&set_c), 0..3);
+    check(set_c.intersection(&set_a), 0..3);
+    check(set_a.union(&set_c), 0..6);
+    check(set_c.union(&set_a), 0..6);
+
+    check(set_c.difference(&set_d), 0..3);
+    check(set_d.difference(&set_c), (6..9).rev());
+    check(
+        set_c.symmetric_difference(&set_d),
+        (0..3).chain((6..9).rev()),
+    );
+    check(set_d.symmetric_difference(&set_c), (6..9).rev().chain(0..3));
+    check(set_c.intersection(&set_d), 3..6);
+    check(set_d.intersection(&set_c), (3..6).rev());
+    check(set_c.union(&set_d), (0..6).chain((6..9).rev()));
+    check(set_d.union(&set_c), (3..9).rev().chain(0..3));
+}
+
+#[test]
+fn ops() {
+    let empty = IndexSet::<i32>::new();
+    let set_a: IndexSet<_> = (0..3).collect();
+    let set_b: IndexSet<_> = (3..6).collect();
+    let set_c: IndexSet<_> = (0..6).collect();
+    let set_d: IndexSet<_> = (3..9).rev().collect();
+
+    #[allow(clippy::eq_op)]
+    {
+        assert_eq!(&set_a & &set_a, set_a);
+        assert_eq!(&set_a | &set_a, set_a);
+        assert_eq!(&set_a ^ &set_a, empty);
+        assert_eq!(&set_a - &set_a, empty);
+    }
+
+    assert_eq!(&set_a & &set_b, empty);
+    assert_eq!(&set_b & &set_a, empty);
+    assert_eq!(&set_a | &set_b, set_c);
+    assert_eq!(&set_b | &set_a, set_c);
+    assert_eq!(&set_a ^ &set_b, set_c);
+    assert_eq!(&set_b ^ &set_a, set_c);
+    assert_eq!(&set_a - &set_b, set_a);
+    assert_eq!(&set_b - &set_a, set_b);
+
+    assert_eq!(&set_a & &set_c, set_a);
+    assert_eq!(&set_c & &set_a, set_a);
+    assert_eq!(&set_a | &set_c, set_c);
+    assert_eq!(&set_c | &set_a, set_c);
+    assert_eq!(&set_a ^ &set_c, set_b);
+    assert_eq!(&set_c ^ &set_a, set_b);
+    assert_eq!(&set_a - &set_c, empty);
+    assert_eq!(&set_c - &set_a, set_b);
+
+    assert_eq!(&set_c & &set_d, set_b);
+    assert_eq!(&set_d & &set_c, set_b);
+    assert_eq!(&set_c | &set_d, &set_a | &set_d);
+    assert_eq!(&set_d | &set_c, &set_a | &set_d);
+    assert_eq!(&set_c ^ &set_d, &set_a | &(&set_d - &set_b));
+    assert_eq!(&set_d ^ &set_c, &set_a | &(&set_d - &set_b));
+    assert_eq!(&set_c - &set_d, set_a);
+    assert_eq!(&set_d - &set_c, &set_d - &set_b);
+}
+
+#[test]
+#[cfg(feature = "std")]
+fn from_array() {
+    let set1 = IndexSet::from([1, 2, 3, 4]);
+    let set2: IndexSet<_> = [1, 2, 3, 4].into();
+
+    assert_eq!(set1, set2);
+}
+
+#[test]
+fn iter_default() {
+    struct Item;
+    fn assert_default<T>()
+    where
+        T: Default + Iterator,
+    {
+        assert!(T::default().next().is_none());
+    }
+    assert_default::<Iter<'static, Item>>();
+    assert_default::<IntoIter<Item>>();
+}
+
+#[test]
+fn test_binary_search_by() {
+    // adapted from std's test for binary_search
+    let b: IndexSet<i32> = [].into();
+    assert_eq!(b.binary_search_by(|x| x.cmp(&5)), Err(0));
+
+    let b: IndexSet<i32> = [4].into();
+    assert_eq!(b.binary_search_by(|x| x.cmp(&3)), Err(0));
+    assert_eq!(b.binary_search_by(|x| x.cmp(&4)), Ok(0));
+    assert_eq!(b.binary_search_by(|x| x.cmp(&5)), Err(1));
+
+    let b: IndexSet<i32> = [1, 2, 4, 6, 8, 9].into();
+    assert_eq!(b.binary_search_by(|x| x.cmp(&5)), Err(3));
+    assert_eq!(b.binary_search_by(|x| x.cmp(&6)), Ok(3));
+    assert_eq!(b.binary_search_by(|x| x.cmp(&7)), Err(4));
+    assert_eq!(b.binary_search_by(|x| x.cmp(&8)), Ok(4));
+
+    let b: IndexSet<i32> = [1, 2, 4, 5, 6, 8].into();
+    assert_eq!(b.binary_search_by(|x| x.cmp(&9)), Err(6));
+
+    let b: IndexSet<i32> = [1, 2, 4, 6, 7, 8, 9].into();
+    assert_eq!(b.binary_search_by(|x| x.cmp(&6)), Ok(3));
+    assert_eq!(b.binary_search_by(|x| x.cmp(&5)), Err(3));
+    assert_eq!(b.binary_search_by(|x| x.cmp(&8)), Ok(5));
+
+    let b: IndexSet<i32> = [1, 2, 4, 5, 6, 8, 9].into();
+    assert_eq!(b.binary_search_by(|x| x.cmp(&7)), Err(5));
+    assert_eq!(b.binary_search_by(|x| x.cmp(&0)), Err(0));
+
+    let b: IndexSet<i32> = [1, 3, 3, 3, 7].into();
+    assert_eq!(b.binary_search_by(|x| x.cmp(&0)), Err(0));
+    assert_eq!(b.binary_search_by(|x| x.cmp(&1)), Ok(0));
+    assert_eq!(b.binary_search_by(|x| x.cmp(&2)), Err(1));
+    // diff from std as set merges the duplicate keys
+    assert!(match b.binary_search_by(|x| x.cmp(&3)) {
+        Ok(1..=2) => true,
+        _ => false,
+    });
+    assert!(match b.binary_search_by(|x| x.cmp(&3)) {
+        Ok(1..=2) => true,
+        _ => false,
+    });
+    assert_eq!(b.binary_search_by(|x| x.cmp(&4)), Err(2));
+    assert_eq!(b.binary_search_by(|x| x.cmp(&5)), Err(2));
+    assert_eq!(b.binary_search_by(|x| x.cmp(&6)), Err(2));
+    assert_eq!(b.binary_search_by(|x| x.cmp(&7)), Ok(2));
+    assert_eq!(b.binary_search_by(|x| x.cmp(&8)), Err(3));
+}
+
+#[test]
+fn test_binary_search_by_key() {
+    // adapted from std's test for binary_search
+    let b: IndexSet<i32> = [].into();
+    assert_eq!(b.binary_search_by_key(&5, |&x| x), Err(0));
+
+    let b: IndexSet<i32> = [4].into();
+    assert_eq!(b.binary_search_by_key(&3, |&x| x), Err(0));
+    assert_eq!(b.binary_search_by_key(&4, |&x| x), Ok(0));
+    assert_eq!(b.binary_search_by_key(&5, |&x| x), Err(1));
+
+    let b: IndexSet<i32> = [1, 2, 4, 6, 8, 9].into();
+    assert_eq!(b.binary_search_by_key(&5, |&x| x), Err(3));
+    assert_eq!(b.binary_search_by_key(&6, |&x| x), Ok(3));
+    assert_eq!(b.binary_search_by_key(&7, |&x| x), Err(4));
+    assert_eq!(b.binary_search_by_key(&8, |&x| x), Ok(4));
+
+    let b: IndexSet<i32> = [1, 2, 4, 5, 6, 8].into();
+    assert_eq!(b.binary_search_by_key(&9, |&x| x), Err(6));
+
+    let b: IndexSet<i32> = [1, 2, 4, 6, 7, 8, 9].into();
+    assert_eq!(b.binary_search_by_key(&6, |&x| x), Ok(3));
+    assert_eq!(b.binary_search_by_key(&5, |&x| x), Err(3));
+    assert_eq!(b.binary_search_by_key(&8, |&x| x), Ok(5));
+
+    let b: IndexSet<i32> = [1, 2, 4, 5, 6, 8, 9].into();
+    assert_eq!(b.binary_search_by_key(&7, |&x| x), Err(5));
+    assert_eq!(b.binary_search_by_key(&0, |&x| x), Err(0));
+
+    let b: IndexSet<i32> = [1, 3, 3, 3, 7].into();
+    assert_eq!(b.binary_search_by_key(&0, |&x| x), Err(0));
+    assert_eq!(b.binary_search_by_key(&1, |&x| x), Ok(0));
+    assert_eq!(b.binary_search_by_key(&2, |&x| x), Err(1));
+    // diff from std as set merges the duplicate keys
+    assert!(match b.binary_search_by_key(&3, |&x| x) {
+        Ok(1..=2) => true,
+        _ => false,
+    });
+    assert!(match b.binary_search_by_key(&3, |&x| x) {
+        Ok(1..=2) => true,
+        _ => false,
+    });
+    assert_eq!(b.binary_search_by_key(&4, |&x| x), Err(2));
+    assert_eq!(b.binary_search_by_key(&5, |&x| x), Err(2));
+    assert_eq!(b.binary_search_by_key(&6, |&x| x), Err(2));
+    assert_eq!(b.binary_search_by_key(&7, |&x| x), Ok(2));
+    assert_eq!(b.binary_search_by_key(&8, |&x| x), Err(3));
+}
+
+#[test]
+fn test_partition_point() {
+    // adapted from std's test for partition_point
+    let b: IndexSet<i32> = [].into();
+    assert_eq!(b.partition_point(|&x| x < 5), 0);
+
+    let b: IndexSet<_> = [4].into();
+    assert_eq!(b.partition_point(|&x| x < 3), 0);
+    assert_eq!(b.partition_point(|&x| x < 4), 0);
+    assert_eq!(b.partition_point(|&x| x < 5), 1);
+
+    let b: IndexSet<_> = [1, 2, 4, 6, 8, 9].into();
+    assert_eq!(b.partition_point(|&x| x < 5), 3);
+    assert_eq!(b.partition_point(|&x| x < 6), 3);
+    assert_eq!(b.partition_point(|&x| x < 7), 4);
+    assert_eq!(b.partition_point(|&x| x < 8), 4);
+
+    let b: IndexSet<_> = [1, 2, 4, 5, 6, 8].into();
+    assert_eq!(b.partition_point(|&x| x < 9), 6);
+
+    let b: IndexSet<_> = [1, 2, 4, 6, 7, 8, 9].into();
+    assert_eq!(b.partition_point(|&x| x < 6), 3);
+    assert_eq!(b.partition_point(|&x| x < 5), 3);
+    assert_eq!(b.partition_point(|&x| x < 8), 5);
+
+    let b: IndexSet<_> = [1, 2, 4, 5, 6, 8, 9].into();
+    assert_eq!(b.partition_point(|&x| x < 7), 5);
+    assert_eq!(b.partition_point(|&x| x < 0), 0);
+
+    let b: IndexSet<_> = [1, 3, 3, 3, 7].into();
+    assert_eq!(b.partition_point(|&x| x < 0), 0);
+    assert_eq!(b.partition_point(|&x| x < 1), 0);
+    assert_eq!(b.partition_point(|&x| x < 2), 1);
+    assert_eq!(b.partition_point(|&x| x < 3), 1);
+    assert_eq!(b.partition_point(|&x| x < 4), 2); // diff from std as set merges the duplicate keys
+    assert_eq!(b.partition_point(|&x| x < 5), 2);
+    assert_eq!(b.partition_point(|&x| x < 6), 2);
+    assert_eq!(b.partition_point(|&x| x < 7), 2);
+    assert_eq!(b.partition_point(|&x| x < 8), 3);
+}
diff --git a/third_party/rust/indexmap/src/util.rs b/third_party/rust/indexmap/src/util.rs
index a24dfafde7..377ff516f0 100644
--- a/third_party/rust/indexmap/src/util.rs
+++ b/third_party/rust/indexmap/src/util.rs
@@ -29,3 +29,25 @@ where
     }
     start..end
 }
+
+pub(crate) fn try_simplify_range<R>(range: R, len: usize) -> Option<Range<usize>>
+where
+    R: RangeBounds<usize>,
+{
+    let start = match range.start_bound() {
+        Bound::Unbounded => 0,
+        Bound::Included(&i) if i <= len => i,
+        Bound::Excluded(&i) if i < len => i + 1,
+        _ => return None,
+    };
+    let end = match range.end_bound() {
+        Bound::Unbounded => len,
+        Bound::Excluded(&i) if i <= len => i,
+        Bound::Included(&i) if i < len => i + 1,
+        _ => return None,
+    };
+    if start > end {
+        return None;
+    }
+    Some(start..end)
+}
diff --git a/third_party/rust/indexmap/tests/quick.rs b/third_party/rust/indexmap/tests/quick.rs
index e9d96acccb..56afee7239 100644
--- a/third_party/rust/indexmap/tests/quick.rs
+++ b/third_party/rust/indexmap/tests/quick.rs
@@ -19,8 +19,8 @@ use std::hash::Hash;
 use std::ops::Bound;
 use std::ops::Deref;
 
-use indexmap::map::Entry as OEntry;
-use std::collections::hash_map::Entry as HEntry;
+use indexmap::map::Entry;
+use std::collections::hash_map::Entry as StdEntry;
 
 fn set<'a, T: 'a, I>(iter: I) -> HashSet<T>
 where
@@ -113,6 +113,23 @@ quickcheck_limit! {
         true
     }
 
+    fn insert_sorted(insert: Vec<(u32, u32)>) -> bool {
+        let mut hmap = HashMap::new();
+        let mut map = IndexMap::new();
+        let mut map2 = IndexMap::new();
+        for &(key, value) in &insert {
+            hmap.insert(key, value);
+            map.insert_sorted(key, value);
+            match map2.entry(key) {
+                Entry::Occupied(e) => *e.into_mut() = value,
+                Entry::Vacant(e) => { e.insert_sorted(value); }
+            }
+        }
+        itertools::assert_equal(hmap.iter().sorted(), &map);
+        itertools::assert_equal(&map, &map2);
+        true
+    }
+
     fn pop(insert: Vec<u8>) -> bool {
         let mut map = IndexMap::new();
         for &key in &insert {
@@ -218,7 +235,7 @@ quickcheck_limit! {
     }
 
     // Use `u8` test indices so quickcheck is less likely to go out of bounds.
-    fn swap_indices(vec: Vec<u8>, a: u8, b: u8) -> TestResult {
+    fn set_swap_indices(vec: Vec<u8>, a: u8, b: u8) -> TestResult {
         let mut set = IndexSet::<u8>::from_iter(vec);
         let a = usize::from(a);
         let b = usize::from(b);
@@ -240,8 +257,39 @@ quickcheck_limit! {
         TestResult::passed()
     }
 
+    fn map_swap_indices(vec: Vec<u8>, from: u8, to: u8) -> TestResult {
+        test_map_swap_indices(vec, from, to, IndexMap::swap_indices)
+    }
+
+    fn occupied_entry_swap_indices(vec: Vec<u8>, from: u8, to: u8) -> TestResult {
+        test_map_swap_indices(vec, from, to, |map, from, to| {
+            let key = map.keys()[from];
+            match map.entry(key) {
+                Entry::Occupied(entry) => entry.swap_indices(to),
+                _ => unreachable!(),
+            }
+        })
+    }
+
+    fn indexed_entry_swap_indices(vec: Vec<u8>, from: u8, to: u8) -> TestResult {
+        test_map_swap_indices(vec, from, to, |map, from, to| {
+            map.get_index_entry(from).unwrap().swap_indices(to);
+        })
+    }
+
+    fn raw_occupied_entry_swap_indices(vec: Vec<u8>, from: u8, to: u8) -> TestResult {
+        use indexmap::map::raw_entry_v1::{RawEntryApiV1, RawEntryMut};
+        test_map_swap_indices(vec, from, to, |map, from, to| {
+            let key = map.keys()[from];
+            match map.raw_entry_mut_v1().from_key(&key) {
+                RawEntryMut::Occupied(entry) => entry.swap_indices(to),
+                _ => unreachable!(),
+            }
+        })
+    }
+
     // Use `u8` test indices so quickcheck is less likely to go out of bounds.
-    fn move_index(vec: Vec<u8>, from: u8, to: u8) -> TestResult {
+    fn set_move_index(vec: Vec<u8>, from: u8, to: u8) -> TestResult {
         let mut set = IndexSet::<u8>::from_iter(vec);
         let from = usize::from(from);
         let to = usize::from(to);
@@ -263,6 +311,138 @@ quickcheck_limit! {
         }));
         TestResult::passed()
     }
+
+    fn map_move_index(vec: Vec<u8>, from: u8, to: u8) -> TestResult {
+        test_map_move_index(vec, from, to, IndexMap::move_index)
+    }
+
+    fn occupied_entry_move_index(vec: Vec<u8>, from: u8, to: u8) -> TestResult {
+        test_map_move_index(vec, from, to, |map, from, to| {
+            let key = map.keys()[from];
+            match map.entry(key) {
+                Entry::Occupied(entry) => entry.move_index(to),
+                _ => unreachable!(),
+            }
+        })
+    }
+
+    fn indexed_entry_move_index(vec: Vec<u8>, from: u8, to: u8) -> TestResult {
+        test_map_move_index(vec, from, to, |map, from, to| {
+            map.get_index_entry(from).unwrap().move_index(to);
+        })
+    }
+
+    fn raw_occupied_entry_move_index(vec: Vec<u8>, from: u8, to: u8) -> TestResult {
+        use indexmap::map::raw_entry_v1::{RawEntryApiV1, RawEntryMut};
+        test_map_move_index(vec, from, to, |map, from, to| {
+            let key = map.keys()[from];
+            match map.raw_entry_mut_v1().from_key(&key) {
+                RawEntryMut::Occupied(entry) => entry.move_index(to),
+                _ => unreachable!(),
+            }
+        })
+    }
+
+    fn occupied_entry_shift_insert(vec: Vec<u8>, i: u8) -> TestResult {
+        test_map_shift_insert(vec, i, |map, i, key| {
+            match map.entry(key) {
+                Entry::Vacant(entry) => entry.shift_insert(i, ()),
+                _ => unreachable!(),
+            };
+        })
+    }
+
+    fn raw_occupied_entry_shift_insert(vec: Vec<u8>, i: u8) -> TestResult {
+        use indexmap::map::raw_entry_v1::{RawEntryApiV1, RawEntryMut};
+        test_map_shift_insert(vec, i, |map, i, key| {
+            match map.raw_entry_mut_v1().from_key(&key) {
+                RawEntryMut::Vacant(entry) => entry.shift_insert(i, key, ()),
+                _ => unreachable!(),
+            };
+        })
+    }
+}
+
+fn test_map_swap_indices<F>(vec: Vec<u8>, a: u8, b: u8, swap_indices: F) -> TestResult
+where
+    F: FnOnce(&mut IndexMap<u8, ()>, usize, usize),
+{
+    let mut map = IndexMap::<u8, ()>::from_iter(vec.into_iter().map(|k| (k, ())));
+    let a = usize::from(a);
+    let b = usize::from(b);
+
+    if a >= map.len() || b >= map.len() {
+        return TestResult::discard();
+    }
+
+    let mut vec = Vec::from_iter(map.keys().copied());
+    vec.swap(a, b);
+
+    swap_indices(&mut map, a, b);
+
+    // Check both iteration order and hash lookups
+    assert!(map.keys().eq(vec.iter()));
+    assert!(vec
+        .iter()
+        .enumerate()
+        .all(|(i, x)| { map.get_index_of(x) == Some(i) }));
+    TestResult::passed()
+}
+
+fn test_map_move_index<F>(vec: Vec<u8>, from: u8, to: u8, move_index: F) -> TestResult
+where
+    F: FnOnce(&mut IndexMap<u8, ()>, usize, usize),
+{
+    let mut map = IndexMap::<u8, ()>::from_iter(vec.into_iter().map(|k| (k, ())));
+    let from = usize::from(from);
+    let to = usize::from(to);
+
+    if from >= map.len() || to >= map.len() {
+        return TestResult::discard();
+    }
+
+    let mut vec = Vec::from_iter(map.keys().copied());
+    let x = vec.remove(from);
+    vec.insert(to, x);
+
+    move_index(&mut map, from, to);
+
+    // Check both iteration order and hash lookups
+    assert!(map.keys().eq(vec.iter()));
+    assert!(vec
+        .iter()
+        .enumerate()
+        .all(|(i, x)| { map.get_index_of(x) == Some(i) }));
+    TestResult::passed()
+}
+
+fn test_map_shift_insert<F>(vec: Vec<u8>, i: u8, shift_insert: F) -> TestResult
+where
+    F: FnOnce(&mut IndexMap<u8, ()>, usize, u8),
+{
+    let mut map = IndexMap::<u8, ()>::from_iter(vec.into_iter().map(|k| (k, ())));
+    let i = usize::from(i);
+    if i >= map.len() {
+        return TestResult::discard();
+    }
+
+    let mut vec = Vec::from_iter(map.keys().copied());
+    let x = vec.pop().unwrap();
+    vec.insert(i, x);
+
+    let (last, ()) = map.pop().unwrap();
+    assert_eq!(x, last);
+    map.shrink_to_fit(); // so we might have to grow and rehash the table
+
+    shift_insert(&mut map, i, last);
+
+    // Check both iteration order and hash lookups
+    assert!(map.keys().eq(vec.iter()));
+    assert!(vec
+        .iter()
+        .enumerate()
+        .all(|(i, x)| { map.get_index_of(x) == Some(i) }));
+    TestResult::passed()
 }
 
 use crate::Op::*;
@@ -310,10 +490,10 @@ where
                 b.remove(k);
             }
             RemoveEntry(ref k) => {
-                if let OEntry::Occupied(ent) = a.entry(k.clone()) {
+                if let Entry::Occupied(ent) = a.entry(k.clone()) {
                     ent.swap_remove_entry();
                 }
-                if let HEntry::Occupied(ent) = b.entry(k.clone()) {
+                if let StdEntry::Occupied(ent) = b.entry(k.clone()) {
                     ent.remove_entry();
                 }
             }
@@ -452,6 +632,12 @@ quickcheck_limit! {
         assert_sorted_by_key(map, |t| t.1);
     }
 
+    fn sort_3(keyvals: Large<Vec<(i8, i8)>>) -> () {
+        let mut map: IndexMap<_, _> = IndexMap::from_iter(keyvals.to_vec());
+        map.sort_by_cached_key(|&k, _| std::cmp::Reverse(k));
+        assert_sorted_by_key(map, |t| std::cmp::Reverse(t.0));
+    }
+
     fn reverse(keyvals: Large<Vec<(i8, i8)>>) -> () {
         let mut map: IndexMap<_, _> = IndexMap::from_iter(keyvals.to_vec());
author	Daniel Baumann <daniel.baumann@progress-linux.org>	2024-06-12 05:43:14 +0000
committer	Daniel Baumann <daniel.baumann@progress-linux.org>	2024-06-12 05:43:14 +0000
commit	8dd16259287f58f9273002717ec4d27e97127719 (patch)
tree	3863e62a53829a84037444beab3abd4ed9dfc7d0 /third_party/rust/indexmap
parent	Releasing progress-linux version 126.0.1-1~progress7.99u1. (diff)
download	firefox-8dd16259287f58f9273002717ec4d27e97127719.tar.xz firefox-8dd16259287f58f9273002717ec4d27e97127719.zip