46 files changed, 350 insertions, 2 deletions

diff --git a/src/test/ui/iterators/array-of-ranges.rs b/tests/ui/iterators/array-of-ranges.rs
index 037540a3e..037540a3e 100644
--- a/src/test/ui/iterators/array-of-ranges.rs
+++ b/tests/ui/iterators/array-of-ranges.rs
diff --git a/src/test/ui/iterators/array.rs b/tests/ui/iterators/array.rs
index 5985c74e1..5985c74e1 100644
--- a/src/test/ui/iterators/array.rs
+++ b/tests/ui/iterators/array.rs
diff --git a/src/test/ui/iterators/bound.rs b/tests/ui/iterators/bound.rs
index bdd99ef8d..bdd99ef8d 100644
--- a/src/test/ui/iterators/bound.rs
+++ b/tests/ui/iterators/bound.rs
diff --git a/src/test/ui/iterators/bound.stderr b/tests/ui/iterators/bound.stderr
index cc7ded498..cc7ded498 100644
--- a/src/test/ui/iterators/bound.stderr
+++ b/tests/ui/iterators/bound.stderr
diff --git a/src/test/ui/iterators/collect-into-array.rs b/tests/ui/iterators/collect-into-array.rs
index 4c424999b..99d0d9bd7 100644
--- a/src/test/ui/iterators/collect-into-array.rs
+++ b/tests/ui/iterators/collect-into-array.rs
@@ -3,5 +3,4 @@ fn main() {
     //~^ ERROR an array of type `[u32; 10]` cannot be built directly from an iterator
     //~| NOTE try collecting into a `Vec<{integer}>`, then using `.try_into()`
     //~| NOTE required by a bound in `collect`
-    //~| NOTE required by a bound introduced by this call
 }
diff --git a/tests/ui/iterators/collect-into-array.stderr b/tests/ui/iterators/collect-into-array.stderr
new file mode 100644
index 000000000..e38745cc1
--- /dev/null
+++ b/tests/ui/iterators/collect-into-array.stderr
@@ -0,0 +1,13 @@
+error[E0277]: an array of type `[u32; 10]` cannot be built directly from an iterator
+  --> $DIR/collect-into-array.rs:2:39
+   |
+LL |     let whatever: [u32; 10] = (0..10).collect();
+   |                                       ^^^^^^^ try collecting into a `Vec<{integer}>`, then using `.try_into()`
+   |
+   = help: the trait `FromIterator<{integer}>` is not implemented for `[u32; 10]`
+note: required by a bound in `collect`
+  --> $SRC_DIR/core/src/iter/traits/iterator.rs:LL:COL
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0277`.
diff --git a/src/test/ui/iterators/collect-into-slice.rs b/tests/ui/iterators/collect-into-slice.rs
index 09832c260..5a8aacb1a 100644
--- a/src/test/ui/iterators/collect-into-slice.rs
+++ b/tests/ui/iterators/collect-into-slice.rs
@@ -13,6 +13,5 @@ fn main() {
     //~| NOTE all local variables must have a statically known size
     //~| NOTE doesn't have a size known at compile-time
     //~| NOTE doesn't have a size known at compile-time
-    //~| NOTE required by a bound introduced by this call
     process_slice(&some_generated_vec);
 }
diff --git a/tests/ui/iterators/collect-into-slice.stderr b/tests/ui/iterators/collect-into-slice.stderr
new file mode 100644
index 000000000..29fff8c51
--- /dev/null
+++ b/tests/ui/iterators/collect-into-slice.stderr
@@ -0,0 +1,33 @@
+error[E0277]: the size for values of type `[i32]` cannot be known at compilation time
+  --> $DIR/collect-into-slice.rs:6:9
+   |
+LL |     let some_generated_vec = (0..10).collect();
+   |         ^^^^^^^^^^^^^^^^^^ doesn't have a size known at compile-time
+   |
+   = help: the trait `Sized` is not implemented for `[i32]`
+   = note: all local variables must have a statically known size
+   = help: unsized locals are gated as an unstable feature
+
+error[E0277]: the size for values of type `[i32]` cannot be known at compilation time
+  --> $DIR/collect-into-slice.rs:6:38
+   |
+LL |     let some_generated_vec = (0..10).collect();
+   |                                      ^^^^^^^ doesn't have a size known at compile-time
+   |
+   = help: the trait `Sized` is not implemented for `[i32]`
+note: required by a bound in `collect`
+  --> $SRC_DIR/core/src/iter/traits/iterator.rs:LL:COL
+
+error[E0277]: a slice of type `[i32]` cannot be built since `[i32]` has no definite size
+  --> $DIR/collect-into-slice.rs:6:38
+   |
+LL |     let some_generated_vec = (0..10).collect();
+   |                                      ^^^^^^^ try explicitly collecting into a `Vec<{integer}>`
+   |
+   = help: the trait `FromIterator<{integer}>` is not implemented for `[i32]`
+note: required by a bound in `collect`
+  --> $SRC_DIR/core/src/iter/traits/iterator.rs:LL:COL
+
+error: aborting due to 3 previous errors
+
+For more information about this error, try `rustc --explain E0277`.
diff --git a/tests/ui/iterators/float_iterator_hint.rs b/tests/ui/iterators/float_iterator_hint.rs
new file mode 100644
index 000000000..a3335ca41
--- /dev/null
+++ b/tests/ui/iterators/float_iterator_hint.rs
@@ -0,0 +1,15 @@
+// #106728
+
+fn main() {
+    for i in 0.2 {
+        //~^ ERROR `{float}` is not an iterator
+        //~| `{float}` is not an iterator
+        //~| NOTE in this expansion of desugaring of `for` loop
+        //~| NOTE in this expansion of desugaring of `for` loop
+        //~| NOTE in this expansion of desugaring of `for` loop
+        //~| NOTE in this expansion of desugaring of `for` loop
+        //~| NOTE if you want to iterate between `start` until a value `end`, use the exclusive range syntax `start..end` or the inclusive range syntax `start..=end`
+        //~| NOTE required for `{float}` to implement `IntoIterator`
+        println!();
+    }
+}
diff --git a/tests/ui/iterators/float_iterator_hint.stderr b/tests/ui/iterators/float_iterator_hint.stderr
new file mode 100644
index 000000000..bae23a1f8
--- /dev/null
+++ b/tests/ui/iterators/float_iterator_hint.stderr
@@ -0,0 +1,13 @@
+error[E0277]: `{float}` is not an iterator
+  --> $DIR/float_iterator_hint.rs:4:14
+   |
+LL |     for i in 0.2 {
+   |              ^^^ `{float}` is not an iterator
+   |
+   = help: the trait `Iterator` is not implemented for `{float}`
+   = note: if you want to iterate between `start` until a value `end`, use the exclusive range syntax `start..end` or the inclusive range syntax `start..=end`
+   = note: required for `{float}` to implement `IntoIterator`
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0277`.
diff --git a/src/test/ui/iterators/integral.rs b/tests/ui/iterators/integral.rs
index 7537c7904..7537c7904 100644
--- a/src/test/ui/iterators/integral.rs
+++ b/tests/ui/iterators/integral.rs
diff --git a/src/test/ui/iterators/integral.stderr b/tests/ui/iterators/integral.stderr
index 047a71f98..c142fec8d 100644
--- a/src/test/ui/iterators/integral.stderr
+++ b/tests/ui/iterators/integral.stderr
@@ -115,6 +115,7 @@ LL |     for _ in 42.0 {}
    |              ^^^^ `{float}` is not an iterator
    |
    = help: the trait `Iterator` is not implemented for `{float}`
+   = note: if you want to iterate between `start` until a value `end`, use the exclusive range syntax `start..end` or the inclusive range syntax `start..=end`
    = note: required for `{float}` to implement `IntoIterator`
 
 error: aborting due to 12 previous errors
diff --git a/src/test/ui/iterators/into-iter-on-arrays-2018.rs b/tests/ui/iterators/into-iter-on-arrays-2018.rs
index 60995170a..60995170a 100644
--- a/src/test/ui/iterators/into-iter-on-arrays-2018.rs
+++ b/tests/ui/iterators/into-iter-on-arrays-2018.rs
diff --git a/src/test/ui/iterators/into-iter-on-arrays-2018.stderr b/tests/ui/iterators/into-iter-on-arrays-2018.stderr
index 2378476e5..2378476e5 100644
--- a/src/test/ui/iterators/into-iter-on-arrays-2018.stderr
+++ b/tests/ui/iterators/into-iter-on-arrays-2018.stderr
diff --git a/src/test/ui/iterators/into-iter-on-arrays-2021.rs b/tests/ui/iterators/into-iter-on-arrays-2021.rs
index 158317efe..158317efe 100644
--- a/src/test/ui/iterators/into-iter-on-arrays-2021.rs
+++ b/tests/ui/iterators/into-iter-on-arrays-2021.rs
diff --git a/src/test/ui/iterators/into-iter-on-arrays-lint.fixed b/tests/ui/iterators/into-iter-on-arrays-lint.fixed
index 6e02a7024..6e02a7024 100644
--- a/src/test/ui/iterators/into-iter-on-arrays-lint.fixed
+++ b/tests/ui/iterators/into-iter-on-arrays-lint.fixed
diff --git a/src/test/ui/iterators/into-iter-on-arrays-lint.rs b/tests/ui/iterators/into-iter-on-arrays-lint.rs
index 582d5cadd..582d5cadd 100644
--- a/src/test/ui/iterators/into-iter-on-arrays-lint.rs
+++ b/tests/ui/iterators/into-iter-on-arrays-lint.rs
diff --git a/src/test/ui/iterators/into-iter-on-arrays-lint.stderr b/tests/ui/iterators/into-iter-on-arrays-lint.stderr
index 2fde276fa..2fde276fa 100644
--- a/src/test/ui/iterators/into-iter-on-arrays-lint.stderr
+++ b/tests/ui/iterators/into-iter-on-arrays-lint.stderr
diff --git a/src/test/ui/iterators/into-iterator-type-inference-shift.rs b/tests/ui/iterators/into-iterator-type-inference-shift.rs
index 9151172fd..9151172fd 100644
--- a/src/test/ui/iterators/into-iterator-type-inference-shift.rs
+++ b/tests/ui/iterators/into-iterator-type-inference-shift.rs
diff --git a/tests/ui/iterators/invalid-iterator-chain-with-int-infer.rs b/tests/ui/iterators/invalid-iterator-chain-with-int-infer.rs
new file mode 100644
index 000000000..882a1d139
--- /dev/null
+++ b/tests/ui/iterators/invalid-iterator-chain-with-int-infer.rs
@@ -0,0 +1,4 @@
+fn main() {
+    let x = Some(()).iter().map(|()| 1).sum::<f32>();
+    //~^ ERROR a value of type `f32` cannot be made by summing an iterator over elements of type `{integer}`
+}
diff --git a/tests/ui/iterators/invalid-iterator-chain-with-int-infer.stderr b/tests/ui/iterators/invalid-iterator-chain-with-int-infer.stderr
new file mode 100644
index 000000000..3cb5e44c7
--- /dev/null
+++ b/tests/ui/iterators/invalid-iterator-chain-with-int-infer.stderr
@@ -0,0 +1,24 @@
+error[E0277]: a value of type `f32` cannot be made by summing an iterator over elements of type `{integer}`
+  --> $DIR/invalid-iterator-chain-with-int-infer.rs:2:41
+   |
+LL |     let x = Some(()).iter().map(|()| 1).sum::<f32>();
+   |                                         ^^^ value of type `f32` cannot be made by summing a `std::iter::Iterator<Item={integer}>`
+   |
+   = help: the trait `Sum<{integer}>` is not implemented for `f32`
+   = help: the following other types implement trait `Sum<A>`:
+             <f32 as Sum<&'a f32>>
+             <f32 as Sum>
+note: the method call chain might not have had the expected associated types
+  --> $DIR/invalid-iterator-chain-with-int-infer.rs:2:29
+   |
+LL |     let x = Some(()).iter().map(|()| 1).sum::<f32>();
+   |             -------- ------ ^^^^^^^^^^^ `Iterator::Item` changed to `{integer}` here
+   |             |        |
+   |             |        `Iterator::Item` is `&()` here
+   |             this expression has type `Option<()>`
+note: required by a bound in `std::iter::Iterator::sum`
+  --> $SRC_DIR/core/src/iter/traits/iterator.rs:LL:COL
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0277`.
diff --git a/tests/ui/iterators/invalid-iterator-chain.rs b/tests/ui/iterators/invalid-iterator-chain.rs
new file mode 100644
index 000000000..ebdf33303
--- /dev/null
+++ b/tests/ui/iterators/invalid-iterator-chain.rs
@@ -0,0 +1,53 @@
+use std::collections::hash_set::Iter;
+use std::collections::HashSet;
+
+fn iter_to_vec<'b, X>(i: Iter<'b, X>) -> Vec<X> {
+    let i = i.map(|x| x.clone());
+    i.collect() //~ ERROR E0277
+}
+
+fn main() {
+    let scores = vec![(0, 0)]
+        .iter()
+        .map(|(a, b)| {
+            a + b;
+        });
+    println!("{}", scores.sum::<i32>()); //~ ERROR E0277
+    println!(
+        "{}",
+        vec![0, 1]
+            .iter()
+            .map(|x| x * 2)
+            .map(|x| x as f64)
+            .map(|x| x as i64)
+            .filter(|x| *x > 0)
+            .map(|x| { x + 1 })
+            .map(|x| { x; })
+            .sum::<i32>(), //~ ERROR E0277
+    );
+    println!(
+        "{}",
+        vec![0, 1]
+            .iter()
+            .map(|x| x * 2)
+            .map(|x| x as f64)
+            .filter(|x| *x > 0.0)
+            .map(|x| { x + 1.0 })
+            .sum::<i32>(), //~ ERROR E0277
+    );
+    println!("{}", vec![0, 1].iter().map(|x| { x; }).sum::<i32>()); //~ ERROR E0277
+    println!("{}", vec![(), ()].iter().sum::<i32>()); //~ ERROR E0277
+    let a = vec![0];
+    let b = a.into_iter();
+    let c = b.map(|x| x + 1);
+    let d = c.filter(|x| *x > 10 );
+    let e = d.map(|x| {
+        x + 1;
+    });
+    let f = e.filter(|_| false);
+    let g: Vec<i32> = f.collect(); //~ ERROR E0277
+
+    let mut s = HashSet::new();
+    s.insert(1u8);
+    println!("{:?}", iter_to_vec(s.iter()));
+}
diff --git a/tests/ui/iterators/invalid-iterator-chain.stderr b/tests/ui/iterators/invalid-iterator-chain.stderr
new file mode 100644
index 000000000..f3dceca7e
--- /dev/null
+++ b/tests/ui/iterators/invalid-iterator-chain.stderr
@@ -0,0 +1,176 @@
+error[E0277]: a value of type `Vec<X>` cannot be built from an iterator over elements of type `&X`
+  --> $DIR/invalid-iterator-chain.rs:6:7
+   |
+LL |     i.collect()
+   |       ^^^^^^^ value of type `Vec<X>` cannot be built from `std::iter::Iterator<Item=&X>`
+   |
+   = help: the trait `FromIterator<&X>` is not implemented for `Vec<X>`
+   = help: the trait `FromIterator<T>` is implemented for `Vec<T>`
+note: the method call chain might not have had the expected associated types
+  --> $DIR/invalid-iterator-chain.rs:4:26
+   |
+LL | fn iter_to_vec<'b, X>(i: Iter<'b, X>) -> Vec<X> {
+   |                          ^^^^^^^^^^^ `Iterator::Item` is `&X` here
+LL |     let i = i.map(|x| x.clone());
+   |               ------------------ `Iterator::Item` remains `&X` here
+note: required by a bound in `collect`
+  --> $SRC_DIR/core/src/iter/traits/iterator.rs:LL:COL
+
+error[E0277]: a value of type `i32` cannot be made by summing an iterator over elements of type `()`
+  --> $DIR/invalid-iterator-chain.rs:15:27
+   |
+LL |     println!("{}", scores.sum::<i32>());
+   |                           ^^^ value of type `i32` cannot be made by summing a `std::iter::Iterator<Item=()>`
+   |
+   = help: the trait `Sum<()>` is not implemented for `i32`
+   = help: the following other types implement trait `Sum<A>`:
+             <i32 as Sum<&'a i32>>
+             <i32 as Sum>
+note: the method call chain might not have had the expected associated types
+  --> $DIR/invalid-iterator-chain.rs:12:10
+   |
+LL |       let scores = vec![(0, 0)]
+   |                    ------------ this expression has type `Vec<({integer}, {integer})>`
+LL |           .iter()
+   |            ------ `Iterator::Item` is `&({integer}, {integer})` here
+LL |           .map(|(a, b)| {
+   |  __________^
+LL | |             a + b;
+LL | |         });
+   | |__________^ `Iterator::Item` changed to `()` here
+note: required by a bound in `std::iter::Iterator::sum`
+  --> $SRC_DIR/core/src/iter/traits/iterator.rs:LL:COL
+
+error[E0277]: a value of type `i32` cannot be made by summing an iterator over elements of type `()`
+  --> $DIR/invalid-iterator-chain.rs:26:14
+   |
+LL |             .sum::<i32>(),
+   |              ^^^ value of type `i32` cannot be made by summing a `std::iter::Iterator<Item=()>`
+   |
+   = help: the trait `Sum<()>` is not implemented for `i32`
+   = help: the following other types implement trait `Sum<A>`:
+             <i32 as Sum<&'a i32>>
+             <i32 as Sum>
+note: the method call chain might not have had the expected associated types
+  --> $DIR/invalid-iterator-chain.rs:25:14
+   |
+LL |         vec![0, 1]
+   |         ---------- this expression has type `Vec<{integer}>`
+LL |             .iter()
+   |              ------ `Iterator::Item` is `&{integer}` here
+LL |             .map(|x| x * 2)
+   |              -------------- `Iterator::Item` changed to `{integer}` here
+LL |             .map(|x| x as f64)
+   |              ----------------- `Iterator::Item` changed to `f64` here
+LL |             .map(|x| x as i64)
+   |              ----------------- `Iterator::Item` changed to `i64` here
+LL |             .filter(|x| *x > 0)
+   |              ------------------ `Iterator::Item` remains `i64` here
+LL |             .map(|x| { x + 1 })
+   |              ------------------ `Iterator::Item` remains `i64` here
+LL |             .map(|x| { x; })
+   |              ^^^^^^^^^^^^^^^ `Iterator::Item` changed to `()` here
+note: required by a bound in `std::iter::Iterator::sum`
+  --> $SRC_DIR/core/src/iter/traits/iterator.rs:LL:COL
+
+error[E0277]: a value of type `i32` cannot be made by summing an iterator over elements of type `f64`
+  --> $DIR/invalid-iterator-chain.rs:36:14
+   |
+LL |             .sum::<i32>(),
+   |              ^^^ value of type `i32` cannot be made by summing a `std::iter::Iterator<Item=f64>`
+   |
+   = help: the trait `Sum<f64>` is not implemented for `i32`
+   = help: the following other types implement trait `Sum<A>`:
+             <i32 as Sum<&'a i32>>
+             <i32 as Sum>
+note: the method call chain might not have had the expected associated types
+  --> $DIR/invalid-iterator-chain.rs:33:14
+   |
+LL |         vec![0, 1]
+   |         ---------- this expression has type `Vec<{integer}>`
+LL |             .iter()
+   |              ------ `Iterator::Item` is `&{integer}` here
+LL |             .map(|x| x * 2)
+   |              -------------- `Iterator::Item` changed to `{integer}` here
+LL |             .map(|x| x as f64)
+   |              ^^^^^^^^^^^^^^^^^ `Iterator::Item` changed to `f64` here
+LL |             .filter(|x| *x > 0.0)
+   |              -------------------- `Iterator::Item` remains `f64` here
+LL |             .map(|x| { x + 1.0 })
+   |              -------------------- `Iterator::Item` remains `f64` here
+note: required by a bound in `std::iter::Iterator::sum`
+  --> $SRC_DIR/core/src/iter/traits/iterator.rs:LL:COL
+
+error[E0277]: a value of type `i32` cannot be made by summing an iterator over elements of type `()`
+  --> $DIR/invalid-iterator-chain.rs:38:54
+   |
+LL |     println!("{}", vec![0, 1].iter().map(|x| { x; }).sum::<i32>());
+   |                                                      ^^^ value of type `i32` cannot be made by summing a `std::iter::Iterator<Item=()>`
+   |
+   = help: the trait `Sum<()>` is not implemented for `i32`
+   = help: the following other types implement trait `Sum<A>`:
+             <i32 as Sum<&'a i32>>
+             <i32 as Sum>
+note: the method call chain might not have had the expected associated types
+  --> $DIR/invalid-iterator-chain.rs:38:38
+   |
+LL |     println!("{}", vec![0, 1].iter().map(|x| { x; }).sum::<i32>());
+   |                    ---------- ------ ^^^^^^^^^^^^^^^ `Iterator::Item` changed to `()` here
+   |                    |          |
+   |                    |          `Iterator::Item` is `&{integer}` here
+   |                    this expression has type `Vec<{integer}>`
+note: required by a bound in `std::iter::Iterator::sum`
+  --> $SRC_DIR/core/src/iter/traits/iterator.rs:LL:COL
+
+error[E0277]: a value of type `i32` cannot be made by summing an iterator over elements of type `&()`
+  --> $DIR/invalid-iterator-chain.rs:39:40
+   |
+LL |     println!("{}", vec![(), ()].iter().sum::<i32>());
+   |                                        ^^^ value of type `i32` cannot be made by summing a `std::iter::Iterator<Item=&()>`
+   |
+   = help: the trait `Sum<&()>` is not implemented for `i32`
+   = help: the following other types implement trait `Sum<A>`:
+             <i32 as Sum<&'a i32>>
+             <i32 as Sum>
+note: the method call chain might not have had the expected associated types
+  --> $DIR/invalid-iterator-chain.rs:39:33
+   |
+LL |     println!("{}", vec![(), ()].iter().sum::<i32>());
+   |                    ------------ ^^^^^^ `Iterator::Item` is `&()` here
+   |                    |
+   |                    this expression has type `Vec<()>`
+note: required by a bound in `std::iter::Iterator::sum`
+  --> $SRC_DIR/core/src/iter/traits/iterator.rs:LL:COL
+
+error[E0277]: a value of type `Vec<i32>` cannot be built from an iterator over elements of type `()`
+  --> $DIR/invalid-iterator-chain.rs:48:25
+   |
+LL |     let g: Vec<i32> = f.collect();
+   |                         ^^^^^^^ value of type `Vec<i32>` cannot be built from `std::iter::Iterator<Item=()>`
+   |
+   = help: the trait `FromIterator<()>` is not implemented for `Vec<i32>`
+   = help: the trait `FromIterator<T>` is implemented for `Vec<T>`
+note: the method call chain might not have had the expected associated types
+  --> $DIR/invalid-iterator-chain.rs:44:15
+   |
+LL |       let a = vec![0];
+   |               ------- this expression has type `Vec<{integer}>`
+LL |       let b = a.into_iter();
+   |                 ----------- `Iterator::Item` is `{integer}` here
+LL |       let c = b.map(|x| x + 1);
+   |                 -------------- `Iterator::Item` remains `{integer}` here
+LL |       let d = c.filter(|x| *x > 10 );
+   |                 -------------------- `Iterator::Item` remains `{integer}` here
+LL |       let e = d.map(|x| {
+   |  _______________^
+LL | |         x + 1;
+LL | |     });
+   | |______^ `Iterator::Item` changed to `()` here
+LL |       let f = e.filter(|_| false);
+   |                 ----------------- `Iterator::Item` remains `()` here
+note: required by a bound in `collect`
+  --> $SRC_DIR/core/src/iter/traits/iterator.rs:LL:COL
+
+error: aborting due to 7 previous errors
+
+For more information about this error, try `rustc --explain E0277`.
diff --git a/src/test/ui/iterators/issue-28098.rs b/tests/ui/iterators/issue-28098.rs
index 80c77edae..80c77edae 100644
--- a/src/test/ui/iterators/issue-28098.rs
+++ b/tests/ui/iterators/issue-28098.rs
diff --git a/src/test/ui/iterators/issue-28098.stderr b/tests/ui/iterators/issue-28098.stderr
index 3256e57d4..3256e57d4 100644
--- a/src/test/ui/iterators/issue-28098.stderr
+++ b/tests/ui/iterators/issue-28098.stderr
diff --git a/src/test/ui/iterators/issue-58952-filter-type-length.rs b/tests/ui/iterators/issue-58952-filter-type-length.rs
index 6d12db8d1..6d12db8d1 100644
--- a/src/test/ui/iterators/issue-58952-filter-type-length.rs
+++ b/tests/ui/iterators/issue-58952-filter-type-length.rs
diff --git a/src/test/ui/iterators/iter-cloned-type-inference.rs b/tests/ui/iterators/iter-cloned-type-inference.rs
index 898e33719..898e33719 100644
--- a/src/test/ui/iterators/iter-cloned-type-inference.rs
+++ b/tests/ui/iterators/iter-cloned-type-inference.rs
diff --git a/src/test/ui/iterators/iter-count-overflow-debug.rs b/tests/ui/iterators/iter-count-overflow-debug.rs
index 8e59c11e9..8e59c11e9 100644
--- a/src/test/ui/iterators/iter-count-overflow-debug.rs
+++ b/tests/ui/iterators/iter-count-overflow-debug.rs
diff --git a/src/test/ui/iterators/iter-count-overflow-ndebug.rs b/tests/ui/iterators/iter-count-overflow-ndebug.rs
index dcaaff671..dcaaff671 100644
--- a/src/test/ui/iterators/iter-count-overflow-ndebug.rs
+++ b/tests/ui/iterators/iter-count-overflow-ndebug.rs
diff --git a/src/test/ui/iterators/iter-map-fold-type-length.rs b/tests/ui/iterators/iter-map-fold-type-length.rs
index 8ce4fcd87..8ce4fcd87 100644
--- a/src/test/ui/iterators/iter-map-fold-type-length.rs
+++ b/tests/ui/iterators/iter-map-fold-type-length.rs
diff --git a/src/test/ui/iterators/iter-position-overflow-debug.rs b/tests/ui/iterators/iter-position-overflow-debug.rs
index 7a871e744..7a871e744 100644
--- a/src/test/ui/iterators/iter-position-overflow-debug.rs
+++ b/tests/ui/iterators/iter-position-overflow-debug.rs
diff --git a/src/test/ui/iterators/iter-position-overflow-ndebug.rs b/tests/ui/iterators/iter-position-overflow-ndebug.rs
index e610c3559..e610c3559 100644
--- a/src/test/ui/iterators/iter-position-overflow-ndebug.rs
+++ b/tests/ui/iterators/iter-position-overflow-ndebug.rs
diff --git a/src/test/ui/iterators/iter-range.rs b/tests/ui/iterators/iter-range.rs
index 993d93790..993d93790 100644
--- a/src/test/ui/iterators/iter-range.rs
+++ b/tests/ui/iterators/iter-range.rs
diff --git a/src/test/ui/iterators/iter-step-overflow-debug.rs b/tests/ui/iterators/iter-step-overflow-debug.rs
index 6aa349ebe..6aa349ebe 100644
--- a/src/test/ui/iterators/iter-step-overflow-debug.rs
+++ b/tests/ui/iterators/iter-step-overflow-debug.rs
diff --git a/src/test/ui/iterators/iter-step-overflow-ndebug.rs b/tests/ui/iterators/iter-step-overflow-ndebug.rs
index 33e708769..33e708769 100644
--- a/src/test/ui/iterators/iter-step-overflow-ndebug.rs
+++ b/tests/ui/iterators/iter-step-overflow-ndebug.rs
diff --git a/src/test/ui/iterators/iter-sum-overflow-debug.rs b/tests/ui/iterators/iter-sum-overflow-debug.rs
index 24c764ff9..24c764ff9 100644
--- a/src/test/ui/iterators/iter-sum-overflow-debug.rs
+++ b/tests/ui/iterators/iter-sum-overflow-debug.rs
diff --git a/src/test/ui/iterators/iter-sum-overflow-ndebug.rs b/tests/ui/iterators/iter-sum-overflow-ndebug.rs
index 69f4744cc..69f4744cc 100644
--- a/src/test/ui/iterators/iter-sum-overflow-ndebug.rs
+++ b/tests/ui/iterators/iter-sum-overflow-ndebug.rs
diff --git a/src/test/ui/iterators/iter-sum-overflow-overflow-checks.rs b/tests/ui/iterators/iter-sum-overflow-overflow-checks.rs
index be45c075d..be45c075d 100644
--- a/src/test/ui/iterators/iter-sum-overflow-overflow-checks.rs
+++ b/tests/ui/iterators/iter-sum-overflow-overflow-checks.rs
diff --git a/src/test/ui/iterators/ranges.rs b/tests/ui/iterators/ranges.rs
index 925d2d61a..925d2d61a 100644
--- a/src/test/ui/iterators/ranges.rs
+++ b/tests/ui/iterators/ranges.rs
diff --git a/src/test/ui/iterators/ranges.stderr b/tests/ui/iterators/ranges.stderr
index b9fbcd530..b9fbcd530 100644
--- a/src/test/ui/iterators/ranges.stderr
+++ b/tests/ui/iterators/ranges.stderr
diff --git a/src/test/ui/iterators/rsplit-clone.rs b/tests/ui/iterators/rsplit-clone.rs
index 911da7429..911da7429 100644
--- a/src/test/ui/iterators/rsplit-clone.rs
+++ b/tests/ui/iterators/rsplit-clone.rs
diff --git a/src/test/ui/iterators/skip-count-overflow.rs b/tests/ui/iterators/skip-count-overflow.rs
index 64dee3e3c..64dee3e3c 100644
--- a/src/test/ui/iterators/skip-count-overflow.rs
+++ b/tests/ui/iterators/skip-count-overflow.rs
diff --git a/src/test/ui/iterators/string.rs b/tests/ui/iterators/string.rs
index ad58a463e..ad58a463e 100644
--- a/src/test/ui/iterators/string.rs
+++ b/tests/ui/iterators/string.rs
diff --git a/src/test/ui/iterators/string.stderr b/tests/ui/iterators/string.stderr
index ddfe0169b..ddfe0169b 100644
--- a/src/test/ui/iterators/string.stderr
+++ b/tests/ui/iterators/string.stderr
diff --git a/src/test/ui/iterators/vec-on-unimplemented.rs b/tests/ui/iterators/vec-on-unimplemented.rs
index 42b5d36bf..42b5d36bf 100644
--- a/src/test/ui/iterators/vec-on-unimplemented.rs
+++ b/tests/ui/iterators/vec-on-unimplemented.rs
diff --git a/tests/ui/iterators/vec-on-unimplemented.stderr b/tests/ui/iterators/vec-on-unimplemented.stderr
new file mode 100644
index 000000000..a7d9c481a
--- /dev/null
+++ b/tests/ui/iterators/vec-on-unimplemented.stderr
@@ -0,0 +1,18 @@
+error[E0599]: `Vec<bool>` is not an iterator
+  --> $DIR/vec-on-unimplemented.rs:2:23
+   |
+LL |     vec![true, false].map(|v| !v).collect::<Vec<_>>();
+   |                       ^^^ `Vec<bool>` is not an iterator; try calling `.into_iter()` or `.iter()`
+  --> $SRC_DIR/alloc/src/vec/mod.rs:LL:COL
+   |
+   = note: doesn't satisfy `Vec<bool>: Iterator`
+   |
+   = note: the following trait bounds were not satisfied:
+           `Vec<bool>: Iterator`
+           which is required by `&mut Vec<bool>: Iterator`
+           `[bool]: Iterator`
+           which is required by `&mut [bool]: Iterator`
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0599`.