Merging upstream version 1.73.0+dfsg1.

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

44 files changed, 1186 insertions, 335 deletions

diff --git a/src/tools/rust-analyzer/crates/ide/src/doc_links.rs b/src/tools/rust-analyzer/crates/ide/src/doc_links.rs
index 8112c4f72..d240127f3 100644
--- a/src/tools/rust-analyzer/crates/ide/src/doc_links.rs
+++ b/src/tools/rust-analyzer/crates/ide/src/doc_links.rs
@@ -153,6 +153,9 @@ pub(crate) fn external_docs(
                 NameRefClass::FieldShorthand { local_ref: _, field_ref } => {
                     Definition::Field(field_ref)
                 }
+                NameRefClass::ExternCrateShorthand { decl, .. } => {
+                    Definition::ExternCrateDecl(decl)
+                }
             },
             ast::Name(name) => match NameClass::classify(sema, &name)? {
                 NameClass::Definition(it) | NameClass::ConstReference(it) => it,
@@ -209,6 +212,7 @@ pub(crate) fn resolve_doc_path_for_def(
         Definition::Macro(it) => it.resolve_doc_path(db, link, ns),
         Definition::Field(it) => it.resolve_doc_path(db, link, ns),
         Definition::SelfType(it) => it.resolve_doc_path(db, link, ns),
+        Definition::ExternCrateDecl(it) => it.resolve_doc_path(db, link, ns),
         Definition::BuiltinAttr(_)
         | Definition::ToolModule(_)
         | Definition::BuiltinType(_)
@@ -330,7 +334,9 @@ fn get_doc_links(
         base_url.and_then(|url| url.join(path).ok())
     };
 
-    let Some((target, file, frag)) = filename_and_frag_for_def(db, def) else { return Default::default(); };
+    let Some((target, file, frag)) = filename_and_frag_for_def(db, def) else {
+        return Default::default();
+    };
 
     let (mut web_url, mut local_url) = get_doc_base_urls(db, target, target_dir, sysroot);
 
@@ -615,6 +621,9 @@ fn filename_and_frag_for_def(
             // FIXME fragment numbering
             return Some((adt, file, Some(String::from("impl"))));
         }
+        Definition::ExternCrateDecl(it) => {
+            format!("{}/index.html", it.name(db).display(db.upcast()))
+        }
         Definition::Local(_)
         | Definition::GenericParam(_)
         | Definition::Label(_)
diff --git a/src/tools/rust-analyzer/crates/ide/src/goto_declaration.rs b/src/tools/rust-analyzer/crates/ide/src/goto_declaration.rs
index e70bc2ec5..c39c696cf 100644
--- a/src/tools/rust-analyzer/crates/ide/src/goto_declaration.rs
+++ b/src/tools/rust-analyzer/crates/ide/src/goto_declaration.rs
@@ -37,11 +37,15 @@ pub(crate) fn goto_declaration(
                 match parent {
                     ast::NameRef(name_ref) => match NameRefClass::classify(&sema, &name_ref)? {
                         NameRefClass::Definition(it) => Some(it),
-                        NameRefClass::FieldShorthand { field_ref, .. } => return field_ref.try_to_nav(db),
+                        NameRefClass::FieldShorthand { field_ref, .. } =>
+                            return field_ref.try_to_nav(db),
+                        NameRefClass::ExternCrateShorthand { decl, .. } =>
+                            return decl.try_to_nav(db),
                     },
                     ast::Name(name) => match NameClass::classify(&sema, &name)? {
                         NameClass::Definition(it) | NameClass::ConstReference(it) => Some(it),
-                        NameClass::PatFieldShorthand { field_ref, .. } => return field_ref.try_to_nav(db),
+                        NameClass::PatFieldShorthand { field_ref, .. } =>
+                            return field_ref.try_to_nav(db),
                     },
                     _ => None
                 }
@@ -53,6 +57,7 @@ pub(crate) fn goto_declaration(
                 Definition::Const(c) => c.as_assoc_item(db),
                 Definition::TypeAlias(ta) => ta.as_assoc_item(db),
                 Definition::Function(f) => f.as_assoc_item(db),
+                Definition::ExternCrateDecl(it) => return it.try_to_nav(db),
                 _ => None,
             }?;
 
@@ -211,4 +216,30 @@ fn main() {
 "#,
         );
     }
+
+    #[test]
+    fn goto_decl_for_extern_crate() {
+        check(
+            r#"
+//- /main.rs crate:main deps:std
+extern crate std$0;
+         /// ^^^
+//- /std/lib.rs crate:std
+// empty
+"#,
+        )
+    }
+
+    #[test]
+    fn goto_decl_for_renamed_extern_crate() {
+        check(
+            r#"
+//- /main.rs crate:main deps:std
+extern crate std as abc$0;
+                /// ^^^
+//- /std/lib.rs crate:std
+// empty
+"#,
+        )
+    }
 }
diff --git a/src/tools/rust-analyzer/crates/ide/src/goto_definition.rs b/src/tools/rust-analyzer/crates/ide/src/goto_definition.rs
index 4e641357e..21471ab2a 100644
--- a/src/tools/rust-analyzer/crates/ide/src/goto_definition.rs
+++ b/src/tools/rust-analyzer/crates/ide/src/goto_definition.rs
@@ -1,6 +1,9 @@
 use std::mem::discriminant;
 
-use crate::{doc_links::token_as_doc_comment, FilePosition, NavigationTarget, RangeInfo, TryToNav};
+use crate::{
+    doc_links::token_as_doc_comment, navigation_target::ToNav, FilePosition, NavigationTarget,
+    RangeInfo, TryToNav,
+};
 use hir::{AsAssocItem, AssocItem, Semantics};
 use ide_db::{
     base_db::{AnchoredPath, FileId, FileLoader},
@@ -73,6 +76,13 @@ pub(crate) fn goto_definition(
                     .definitions()
                     .into_iter()
                     .flat_map(|def| {
+                        if let Definition::ExternCrateDecl(crate_def) = def {
+                            return crate_def
+                                .resolved_crate(db)
+                                .map(|it| it.root_module().to_nav(sema.db))
+                                .into_iter()
+                                .collect();
+                        }
                         try_filter_trait_item_definition(sema, &def)
                             .unwrap_or_else(|| def_to_nav(sema.db, def))
                     })
diff --git a/src/tools/rust-analyzer/crates/ide/src/goto_implementation.rs b/src/tools/rust-analyzer/crates/ide/src/goto_implementation.rs
index a1a119629..37166bdbd 100644
--- a/src/tools/rust-analyzer/crates/ide/src/goto_implementation.rs
+++ b/src/tools/rust-analyzer/crates/ide/src/goto_implementation.rs
@@ -34,54 +34,50 @@ pub(crate) fn goto_implementation(
             _ => 0,
         })?;
     let range = original_token.text_range();
-    let navs = sema
-        .descend_into_macros(original_token)
-        .into_iter()
-        .filter_map(|token| token.parent().and_then(ast::NameLike::cast))
-        .filter_map(|node| match &node {
-            ast::NameLike::Name(name) => {
-                NameClass::classify(&sema, name).map(|class| match class {
-                    NameClass::Definition(it) | NameClass::ConstReference(it) => it,
-                    NameClass::PatFieldShorthand { local_def, field_ref: _ } => {
-                        Definition::Local(local_def)
+    let navs =
+        sema.descend_into_macros(original_token)
+            .into_iter()
+            .filter_map(|token| token.parent().and_then(ast::NameLike::cast))
+            .filter_map(|node| match &node {
+                ast::NameLike::Name(name) => {
+                    NameClass::classify(&sema, name).and_then(|class| match class {
+                        NameClass::Definition(it) | NameClass::ConstReference(it) => Some(it),
+                        NameClass::PatFieldShorthand { .. } => None,
+                    })
+                }
+                ast::NameLike::NameRef(name_ref) => NameRefClass::classify(&sema, name_ref)
+                    .and_then(|class| match class {
+                        NameRefClass::Definition(def) => Some(def),
+                        NameRefClass::FieldShorthand { .. }
+                        | NameRefClass::ExternCrateShorthand { .. } => None,
+                    }),
+                ast::NameLike::Lifetime(_) => None,
+            })
+            .unique()
+            .filter_map(|def| {
+                let navs = match def {
+                    Definition::Trait(trait_) => impls_for_trait(&sema, trait_),
+                    Definition::Adt(adt) => impls_for_ty(&sema, adt.ty(sema.db)),
+                    Definition::TypeAlias(alias) => impls_for_ty(&sema, alias.ty(sema.db)),
+                    Definition::BuiltinType(builtin) => impls_for_ty(&sema, builtin.ty(sema.db)),
+                    Definition::Function(f) => {
+                        let assoc = f.as_assoc_item(sema.db)?;
+                        let name = assoc.name(sema.db)?;
+                        let trait_ = assoc.containing_trait_or_trait_impl(sema.db)?;
+                        impls_for_trait_item(&sema, trait_, name)
                     }
-                })
-            }
-            ast::NameLike::NameRef(name_ref) => {
-                NameRefClass::classify(&sema, name_ref).map(|class| match class {
-                    NameRefClass::Definition(def) => def,
-                    NameRefClass::FieldShorthand { local_ref, field_ref: _ } => {
-                        Definition::Local(local_ref)
+                    Definition::Const(c) => {
+                        let assoc = c.as_assoc_item(sema.db)?;
+                        let name = assoc.name(sema.db)?;
+                        let trait_ = assoc.containing_trait_or_trait_impl(sema.db)?;
+                        impls_for_trait_item(&sema, trait_, name)
                     }
-                })
-            }
-            ast::NameLike::Lifetime(_) => None,
-        })
-        .unique()
-        .filter_map(|def| {
-            let navs = match def {
-                Definition::Trait(trait_) => impls_for_trait(&sema, trait_),
-                Definition::Adt(adt) => impls_for_ty(&sema, adt.ty(sema.db)),
-                Definition::TypeAlias(alias) => impls_for_ty(&sema, alias.ty(sema.db)),
-                Definition::BuiltinType(builtin) => impls_for_ty(&sema, builtin.ty(sema.db)),
-                Definition::Function(f) => {
-                    let assoc = f.as_assoc_item(sema.db)?;
-                    let name = assoc.name(sema.db)?;
-                    let trait_ = assoc.containing_trait_or_trait_impl(sema.db)?;
-                    impls_for_trait_item(&sema, trait_, name)
-                }
-                Definition::Const(c) => {
-                    let assoc = c.as_assoc_item(sema.db)?;
-                    let name = assoc.name(sema.db)?;
-                    let trait_ = assoc.containing_trait_or_trait_impl(sema.db)?;
-                    impls_for_trait_item(&sema, trait_, name)
-                }
-                _ => return None,
-            };
-            Some(navs)
-        })
-        .flatten()
-        .collect();
+                    _ => return None,
+                };
+                Some(navs)
+            })
+            .flatten()
+            .collect();
 
     Some(RangeInfo { range, info: navs })
 }
diff --git a/src/tools/rust-analyzer/crates/ide/src/highlight_related.rs b/src/tools/rust-analyzer/crates/ide/src/highlight_related.rs
index 7e545491f..43e89a334 100644
--- a/src/tools/rust-analyzer/crates/ide/src/highlight_related.rs
+++ b/src/tools/rust-analyzer/crates/ide/src/highlight_related.rs
@@ -100,10 +100,7 @@ fn highlight_closure_captures(
             .flat_map(|local| {
                 let usages = Definition::Local(local)
                     .usages(sema)
-                    .set_scope(Some(SearchScope::file_range(FileRange {
-                        file_id,
-                        range: search_range,
-                    })))
+                    .in_scope(&SearchScope::file_range(FileRange { file_id, range: search_range }))
                     .include_self_refs()
                     .all()
                     .references
@@ -139,7 +136,7 @@ fn highlight_references(
         .iter()
         .filter_map(|&d| {
             d.usages(sema)
-                .set_scope(Some(SearchScope::single_file(file_id)))
+                .in_scope(&SearchScope::single_file(file_id))
                 .include_self_refs()
                 .all()
                 .references
@@ -183,7 +180,7 @@ fn highlight_references(
                         .filter_map(|item| {
                             Definition::from(item)
                                 .usages(sema)
-                                .set_scope(Some(SearchScope::file_range(FileRange {
+                                .set_scope(Some(&SearchScope::file_range(FileRange {
                                     file_id,
                                     range: trait_item_use_scope.text_range(),
                                 })))
diff --git a/src/tools/rust-analyzer/crates/ide/src/hover.rs b/src/tools/rust-analyzer/crates/ide/src/hover.rs
index 5ef6ac948..40659e6c2 100644
--- a/src/tools/rust-analyzer/crates/ide/src/hover.rs
+++ b/src/tools/rust-analyzer/crates/ide/src/hover.rs
@@ -9,7 +9,7 @@ use either::Either;
 use hir::{db::DefDatabase, HasSource, LangItem, Semantics};
 use ide_db::{
     base_db::FileRange,
-    defs::{Definition, IdentClass, OperatorClass},
+    defs::{Definition, IdentClass, NameRefClass, OperatorClass},
     famous_defs::FamousDefs,
     helpers::pick_best_token,
     FxIndexSet, RootDatabase,
@@ -186,7 +186,20 @@ fn hover_simple(
                         // rendering poll is very confusing
                         return None;
                     }
-                    Some(class.definitions().into_iter().zip(iter::once(node).cycle()))
+                    if let IdentClass::NameRefClass(NameRefClass::ExternCrateShorthand {
+                        decl,
+                        ..
+                    }) = class
+                    {
+                        return Some(vec![(Definition::ExternCrateDecl(decl), node)]);
+                    }
+                    Some(
+                        class
+                            .definitions()
+                            .into_iter()
+                            .zip(iter::once(node).cycle())
+                            .collect::<Vec<_>>(),
+                    )
                 })
                 .flatten()
                 .unique_by(|&(def, _)| def)
diff --git a/src/tools/rust-analyzer/crates/ide/src/hover/render.rs b/src/tools/rust-analyzer/crates/ide/src/hover/render.rs
index 136214641..a33a6ee18 100644
--- a/src/tools/rust-analyzer/crates/ide/src/hover/render.rs
+++ b/src/tools/rust-analyzer/crates/ide/src/hover/render.rs
@@ -257,7 +257,7 @@ pub(super) fn keyword(
     let KeywordHint { description, keyword_mod, actions } = keyword_hints(sema, token, parent);
 
     let doc_owner = find_std_module(&famous_defs, &keyword_mod)?;
-    let docs = doc_owner.attrs(sema.db).docs()?;
+    let docs = doc_owner.docs(sema.db)?;
     let markup = process_markup(
         sema.db,
         Definition::Module(doc_owner),
@@ -422,10 +422,10 @@ pub(super) fn definition(
             |&it| {
                 if !it.parent_enum(db).is_data_carrying(db) {
                     match it.eval(db) {
-                        Ok(x) => {
-                            Some(if x >= 10 { format!("{x} ({x:#X})") } else { format!("{x}") })
+                        Ok(it) => {
+                            Some(if it >= 10 { format!("{it} ({it:#X})") } else { format!("{it}") })
                         }
-                        Err(_) => it.value(db).map(|x| format!("{x:?}")),
+                        Err(_) => it.value(db).map(|it| format!("{it:?}")),
                     }
                 } else {
                     None
@@ -437,7 +437,7 @@ pub(super) fn definition(
         Definition::Const(it) => label_value_and_docs(db, it, |it| {
             let body = it.render_eval(db);
             match body {
-                Ok(x) => Some(x),
+                Ok(it) => Some(it),
                 Err(_) => {
                     let source = it.source(db)?;
                     let mut body = source.value.body()?.syntax().clone();
@@ -472,6 +472,7 @@ pub(super) fn definition(
         }
         Definition::GenericParam(it) => label_and_docs(db, it),
         Definition::Label(it) => return Some(Markup::fenced_block(&it.name(db).display(db))),
+        Definition::ExternCrateDecl(it) => label_and_docs(db, it),
         // FIXME: We should be able to show more info about these
         Definition::BuiltinAttr(it) => return render_builtin_attr(db, it),
         Definition::ToolModule(it) => return Some(Markup::fenced_block(&it.name(db))),
@@ -620,7 +621,7 @@ where
     D: HasAttrs + HirDisplay,
 {
     let label = def.display(db).to_string();
-    let docs = def.attrs(db).docs();
+    let docs = def.docs(db);
     (label, docs)
 }
 
@@ -645,7 +646,7 @@ where
     ) {
         format_to!(label, "{layout}");
     }
-    let docs = def.attrs(db).docs();
+    let docs = def.docs(db);
     (label, docs)
 }
 
@@ -677,7 +678,7 @@ where
     ) {
         format_to!(label, "{layout}");
     }
-    let docs = def.attrs(db).docs();
+    let docs = def.docs(db);
     (label, docs)
 }
 
@@ -696,7 +697,7 @@ where
     } else {
         def.display(db).to_string()
     };
-    let docs = def.attrs(db).docs();
+    let docs = def.docs(db);
     (label, docs)
 }
 
@@ -727,14 +728,14 @@ fn builtin(famous_defs: &FamousDefs<'_, '_>, builtin: hir::BuiltinType) -> Optio
     // std exposes prim_{} modules with docstrings on the root to document the builtins
     let primitive_mod = format!("prim_{}", builtin.name().display(famous_defs.0.db));
     let doc_owner = find_std_module(famous_defs, &primitive_mod)?;
-    let docs = doc_owner.attrs(famous_defs.0.db).docs()?;
+    let docs = doc_owner.docs(famous_defs.0.db)?;
     markup(Some(docs.into()), builtin.name().display(famous_defs.0.db).to_string(), None)
 }
 
 fn find_std_module(famous_defs: &FamousDefs<'_, '_>, name: &str) -> Option<hir::Module> {
     let db = famous_defs.0.db;
     let std_crate = famous_defs.std()?;
-    let std_root_module = std_crate.root_module(db);
+    let std_root_module = std_crate.root_module();
     std_root_module.children(db).find(|module| {
         module.name(db).map_or(false, |module| module.display(db).to_string() == name)
     })
diff --git a/src/tools/rust-analyzer/crates/ide/src/hover/tests.rs b/src/tools/rust-analyzer/crates/ide/src/hover/tests.rs
index f75ebfa12..ddc71dffa 100644
--- a/src/tools/rust-analyzer/crates/ide/src/hover/tests.rs
+++ b/src/tools/rust-analyzer/crates/ide/src/hover/tests.rs
@@ -674,7 +674,7 @@ struct Foo { fiel$0d_a: u8, field_b: i32, field_c: i16 }
             ```
 
             ```rust
-            field_a: u8 // size = 1, align = 1, offset = 4
+            field_a: u8 // size = 1, align = 1, offset = 6
             ```
         "#]],
     );
@@ -779,6 +779,39 @@ const foo$0: u32 = {
             ```
         "#]],
     );
+
+    check(
+        r#"const FOO$0: i32 = -2147483648;"#,
+        expect![[r#"
+            *FOO*
+
+            ```rust
+            test
+            ```
+
+            ```rust
+            const FOO: i32 = -2147483648 (0x80000000)
+            ```
+        "#]],
+    );
+
+    check(
+        r#"
+        const FOO: i32 = -2147483648;
+        const BAR$0: bool = FOO > 0;
+        "#,
+        expect![[r#"
+            *BAR*
+
+            ```rust
+            test
+            ```
+
+            ```rust
+            const BAR: bool = false
+            ```
+        "#]],
+    );
 }
 
 #[test]
@@ -1583,6 +1616,9 @@ fn test_hover_extern_crate() {
     check(
         r#"
 //- /main.rs crate:main deps:std
+//! Crate docs
+
+/// Decl docs!
 extern crate st$0d;
 //- /std/lib.rs crate:std
 //! Standard library for this test
@@ -1591,23 +1627,32 @@ extern crate st$0d;
 //! abc123
 "#,
         expect![[r#"
-                *std*
+            *std*
 
-                ```rust
-                extern crate std
-                ```
+            ```rust
+            main
+            ```
 
-                ---
+            ```rust
+            extern crate std
+            ```
+
+            ---
 
-                Standard library for this test
+            Decl docs!
 
-                Printed?
-                abc123
-            "#]],
+            Standard library for this test
+
+            Printed?
+            abc123
+        "#]],
     );
     check(
         r#"
 //- /main.rs crate:main deps:std
+//! Crate docs
+
+/// Decl docs!
 extern crate std as ab$0c;
 //- /std/lib.rs crate:std
 //! Standard library for this test
@@ -1616,19 +1661,25 @@ extern crate std as ab$0c;
 //! abc123
 "#,
         expect![[r#"
-                *abc*
+            *abc*
 
-                ```rust
-                extern crate std
-                ```
+            ```rust
+            main
+            ```
 
-                ---
+            ```rust
+            extern crate std as abc
+            ```
 
-                Standard library for this test
+            ---
 
-                Printed?
-                abc123
-            "#]],
+            Decl docs!
+
+            Standard library for this test
+
+            Printed?
+            abc123
+        "#]],
     );
 }
 
diff --git a/src/tools/rust-analyzer/crates/ide/src/inlay_hints/adjustment.rs b/src/tools/rust-analyzer/crates/ide/src/inlay_hints/adjustment.rs
index 10bee2a6a..6d6bd315e 100644
--- a/src/tools/rust-analyzer/crates/ide/src/inlay_hints/adjustment.rs
+++ b/src/tools/rust-analyzer/crates/ide/src/inlay_hints/adjustment.rs
@@ -259,7 +259,7 @@ fn needs_parens_for_adjustment_hints(expr: &ast::Expr, postfix: bool) -> (bool,
         }
     })() else {
         never!("broken syntax tree?\n{:?}\n{:?}", expr, dummy_expr);
-        return (true, true)
+        return (true, true);
     };
 
     // At this point
diff --git a/src/tools/rust-analyzer/crates/ide/src/inlay_hints/chaining.rs b/src/tools/rust-analyzer/crates/ide/src/inlay_hints/chaining.rs
index 84eac16b9..b621a8dda 100644
--- a/src/tools/rust-analyzer/crates/ide/src/inlay_hints/chaining.rs
+++ b/src/tools/rust-analyzer/crates/ide/src/inlay_hints/chaining.rs
@@ -474,7 +474,7 @@ fn main() {
                                         file_id: FileId(
                                             1,
                                         ),
-                                        range: 9287..9295,
+                                        range: 9289..9297,
                                     },
                                 ),
                                 tooltip: "",
@@ -487,7 +487,7 @@ fn main() {
                                         file_id: FileId(
                                             1,
                                         ),
-                                        range: 9319..9323,
+                                        range: 9321..9325,
                                     },
                                 ),
                                 tooltip: "",
@@ -511,7 +511,7 @@ fn main() {
                                         file_id: FileId(
                                             1,
                                         ),
-                                        range: 9287..9295,
+                                        range: 9289..9297,
                                     },
                                 ),
                                 tooltip: "",
@@ -524,7 +524,7 @@ fn main() {
                                         file_id: FileId(
                                             1,
                                         ),
-                                        range: 9319..9323,
+                                        range: 9321..9325,
                                     },
                                 ),
                                 tooltip: "",
@@ -548,7 +548,7 @@ fn main() {
                                         file_id: FileId(
                                             1,
                                         ),
-                                        range: 9287..9295,
+                                        range: 9289..9297,
                                     },
                                 ),
                                 tooltip: "",
@@ -561,7 +561,7 @@ fn main() {
                                         file_id: FileId(
                                             1,
                                         ),
-                                        range: 9319..9323,
+                                        range: 9321..9325,
                                     },
                                 ),
                                 tooltip: "",
diff --git a/src/tools/rust-analyzer/crates/ide/src/interpret_function.rs b/src/tools/rust-analyzer/crates/ide/src/interpret_function.rs
index cbcbb4b09..d06ffd535 100644
--- a/src/tools/rust-analyzer/crates/ide/src/interpret_function.rs
+++ b/src/tools/rust-analyzer/crates/ide/src/interpret_function.rs
@@ -34,13 +34,15 @@ fn find_and_interpret(db: &RootDatabase, position: FilePosition) -> Option<Strin
         _ => return None,
     };
     let span_formatter = |file_id, text_range: TextRange| {
-        let line_col = db.line_index(file_id).line_col(text_range.start());
         let path = &db
             .source_root(db.file_source_root(file_id))
             .path_for_file(&file_id)
             .map(|x| x.to_string());
         let path = path.as_deref().unwrap_or("<unknown file>");
-        format!("file://{path}#{}:{}", line_col.line + 1, line_col.col)
+        match db.line_index(file_id).try_line_col(text_range.start()) {
+            Some(line_col) => format!("file://{path}#{}:{}", line_col.line + 1, line_col.col),
+            None => format!("file://{path} range {:?}", text_range),
+        }
     };
     Some(def.eval(db, span_formatter))
 }
diff --git a/src/tools/rust-analyzer/crates/ide/src/lib.rs b/src/tools/rust-analyzer/crates/ide/src/lib.rs
index f195f78b3..bf77d55d5 100644
--- a/src/tools/rust-analyzer/crates/ide/src/lib.rs
+++ b/src/tools/rust-analyzer/crates/ide/src/lib.rs
@@ -60,6 +60,7 @@ mod interpret_function;
 mod view_item_tree;
 mod shuffle_crate_graph;
 mod fetch_crates;
+mod view_memory_layout;
 
 use std::ffi::OsStr;
 
@@ -74,6 +75,7 @@ use ide_db::{
 };
 use syntax::SourceFile;
 use triomphe::Arc;
+use view_memory_layout::{view_memory_layout, RecursiveMemoryLayout};
 
 use crate::navigation_target::{ToNav, TryToNav};
 
@@ -125,7 +127,7 @@ pub use ide_db::{
     label::Label,
     line_index::{LineCol, LineIndex},
     search::{ReferenceCategory, SearchScope},
-    source_change::{FileSystemEdit, SourceChange},
+    source_change::{FileSystemEdit, SnippetEdit, SourceChange},
     symbol_index::Query,
     RootDatabase, SymbolKind,
 };
@@ -642,7 +644,7 @@ impl Analysis {
         };
 
         self.with_db(|db| {
-            let diagnostic_assists = if include_fixes {
+            let diagnostic_assists = if diagnostics_config.enabled && include_fixes {
                 ide_diagnostics::diagnostics(db, diagnostics_config, &resolve, frange.file_id)
                     .into_iter()
                     .flat_map(|it| it.fixes.unwrap_or_default())
@@ -724,6 +726,13 @@ impl Analysis {
         self.with_db(|db| move_item::move_item(db, range, direction))
     }
 
+    pub fn get_recursive_memory_layout(
+        &self,
+        position: FilePosition,
+    ) -> Cancellable<Option<RecursiveMemoryLayout>> {
+        self.with_db(|db| view_memory_layout(db, position))
+    }
+
     /// Performs an operation on the database that may be canceled.
     ///
     /// rust-analyzer needs to be able to answer semantic questions about the
diff --git a/src/tools/rust-analyzer/crates/ide/src/moniker.rs b/src/tools/rust-analyzer/crates/ide/src/moniker.rs
index 0d57e63d2..17f3771b1 100644
--- a/src/tools/rust-analyzer/crates/ide/src/moniker.rs
+++ b/src/tools/rust-analyzer/crates/ide/src/moniker.rs
@@ -177,6 +177,17 @@ pub(crate) fn def_to_moniker(
         });
     }
 
+    // Qualify locals/parameters by their parent definition name.
+    if let Definition::Local(it) = def {
+        let parent_name = it.parent(db).name(db);
+        if let Some(name) = parent_name {
+            description.push(MonikerDescriptor {
+                name: name.display(db).to_string(),
+                desc: MonikerDescriptorKind::Method,
+            });
+        }
+    }
+
     let name_desc = match def {
         // These are handled by top-level guard (for performance).
         Definition::GenericParam(_)
@@ -247,6 +258,10 @@ pub(crate) fn def_to_moniker(
             name: s.name(db).display(db).to_string(),
             desc: MonikerDescriptorKind::Meta,
         },
+        Definition::ExternCrateDecl(m) => MonikerDescriptor {
+            name: m.name(db).display(db).to_string(),
+            desc: MonikerDescriptorKind::Namespace,
+        },
     };
 
     description.push(name_desc);
@@ -320,7 +335,7 @@ use foo::module::func;
 fn main() {
     func$0();
 }
-//- /foo/lib.rs crate:foo@CratesIo:0.1.0,https://a.b/foo.git
+//- /foo/lib.rs crate:foo@0.1.0,https://a.b/foo.git library
 pub mod module {
     pub fn func() {}
 }
@@ -336,7 +351,7 @@ use foo::module::func;
 fn main() {
     func();
 }
-//- /foo/lib.rs crate:foo@CratesIo:0.1.0,https://a.b/foo.git
+//- /foo/lib.rs crate:foo@0.1.0,https://a.b/foo.git library
 pub mod module {
     pub fn func$0() {}
 }
@@ -351,7 +366,7 @@ pub mod module {
     fn moniker_for_trait() {
         check_moniker(
             r#"
-//- /foo/lib.rs crate:foo@CratesIo:0.1.0,https://a.b/foo.git
+//- /foo/lib.rs crate:foo@0.1.0,https://a.b/foo.git library
 pub mod module {
     pub trait MyTrait {
         pub fn func$0() {}
@@ -368,7 +383,7 @@ pub mod module {
     fn moniker_for_trait_constant() {
         check_moniker(
             r#"
-//- /foo/lib.rs crate:foo@CratesIo:0.1.0,https://a.b/foo.git
+//- /foo/lib.rs crate:foo@0.1.0,https://a.b/foo.git library
 pub mod module {
     pub trait MyTrait {
         const MY_CONST$0: u8;
@@ -385,7 +400,7 @@ pub mod module {
     fn moniker_for_trait_type() {
         check_moniker(
             r#"
-//- /foo/lib.rs crate:foo@CratesIo:0.1.0,https://a.b/foo.git
+//- /foo/lib.rs crate:foo@0.1.0,https://a.b/foo.git library
 pub mod module {
     pub trait MyTrait {
         type MyType$0;
@@ -402,7 +417,7 @@ pub mod module {
     fn moniker_for_trait_impl_function() {
         check_moniker(
             r#"
-//- /foo/lib.rs crate:foo@CratesIo:0.1.0,https://a.b/foo.git
+//- /foo/lib.rs crate:foo@0.1.0,https://a.b/foo.git library
 pub mod module {
     pub trait MyTrait {
         pub fn func() {}
@@ -430,7 +445,7 @@ use foo::St;
 fn main() {
     let x = St { a$0: 2 };
 }
-//- /foo/lib.rs crate:foo@CratesIo:0.1.0,https://a.b/foo.git
+//- /foo/lib.rs crate:foo@0.1.0,https://a.b/foo.git library
 pub struct St {
     pub a: i32,
 }
@@ -450,7 +465,7 @@ use foo::module::func;
 fn main() {
     func();
 }
-//- /foo/lib.rs crate:foo@CratesIo:0.1.0,https://a.b/foo.git
+//- /foo/lib.rs crate:foo@0.1.0,https://a.b/foo.git library
 pub mod module {
     pub fn func() {
         let x$0 = 2;
diff --git a/src/tools/rust-analyzer/crates/ide/src/navigation_target.rs b/src/tools/rust-analyzer/crates/ide/src/navigation_target.rs
index 385c1b0c0..d1479dd1e 100644
--- a/src/tools/rust-analyzer/crates/ide/src/navigation_target.rs
+++ b/src/tools/rust-analyzer/crates/ide/src/navigation_target.rs
@@ -102,7 +102,7 @@ impl NavigationTarget {
                 full_range,
                 SymbolKind::Module,
             );
-            res.docs = module.attrs(db).docs();
+            res.docs = module.docs(db);
             res.description = Some(module.display(db).to_string());
             return res;
         }
@@ -217,6 +217,7 @@ impl TryToNav for Definition {
             Definition::Trait(it) => it.try_to_nav(db),
             Definition::TraitAlias(it) => it.try_to_nav(db),
             Definition::TypeAlias(it) => it.try_to_nav(db),
+            Definition::ExternCrateDecl(it) => Some(it.try_to_nav(db)?),
             Definition::BuiltinType(_) => None,
             Definition::ToolModule(_) => None,
             Definition::BuiltinAttr(_) => None,
@@ -357,13 +358,11 @@ impl ToNav for hir::Module {
 impl TryToNav for hir::Impl {
     fn try_to_nav(&self, db: &RootDatabase) -> Option<NavigationTarget> {
         let InFile { file_id, value } = self.source(db)?;
-        let derive_attr = self.is_builtin_derive(db);
+        let derive_attr = self.as_builtin_derive(db);
 
-        let focus = if derive_attr.is_some() { None } else { value.self_ty() };
-
-        let syntax = match &derive_attr {
-            Some(attr) => attr.value.syntax(),
-            None => value.syntax(),
+        let (focus, syntax) = match &derive_attr {
+            Some(attr) => (None, attr.value.syntax()),
+            None => (value.self_ty(), value.syntax()),
         };
 
         let (file_id, full_range, focus_range) = orig_range_with_focus(db, file_id, syntax, focus);
@@ -377,6 +376,30 @@ impl TryToNav for hir::Impl {
     }
 }
 
+impl TryToNav for hir::ExternCrateDecl {
+    fn try_to_nav(&self, db: &RootDatabase) -> Option<NavigationTarget> {
+        let src = self.source(db)?;
+        let InFile { file_id, value } = src;
+        let focus = value
+            .rename()
+            .map_or_else(|| value.name_ref().map(Either::Left), |it| it.name().map(Either::Right));
+        let (file_id, full_range, focus_range) =
+            orig_range_with_focus(db, file_id, value.syntax(), focus);
+        let mut res = NavigationTarget::from_syntax(
+            file_id,
+            self.alias_or_name(db).unwrap_or_else(|| self.name(db)).to_smol_str(),
+            focus_range,
+            full_range,
+            SymbolKind::Module,
+        );
+
+        res.docs = self.docs(db);
+        res.description = Some(self.display(db).to_string());
+        res.container_name = container_name(db, *self);
+        Some(res)
+    }
+}
+
 impl TryToNav for hir::Field {
     fn try_to_nav(&self, db: &RootDatabase) -> Option<NavigationTarget> {
         let src = self.source(db)?;
diff --git a/src/tools/rust-analyzer/crates/ide/src/references.rs b/src/tools/rust-analyzer/crates/ide/src/references.rs
index fdc5261ac..813f9ed94 100644
--- a/src/tools/rust-analyzer/crates/ide/src/references.rs
+++ b/src/tools/rust-analyzer/crates/ide/src/references.rs
@@ -74,7 +74,7 @@ pub(crate) fn find_all_refs(
                 }
             });
             let mut usages =
-                def.usages(sema).set_scope(search_scope.clone()).include_self_refs().all();
+                def.usages(sema).set_scope(search_scope.as_ref()).include_self_refs().all();
 
             if literal_search {
                 retain_adt_literal_usages(&mut usages, def, sema);
@@ -137,6 +137,9 @@ pub(crate) fn find_defs<'a>(
                             NameRefClass::FieldShorthand { local_ref, field_ref: _ } => {
                                 Definition::Local(local_ref)
                             }
+                            NameRefClass::ExternCrateShorthand { decl, .. } => {
+                                Definition::ExternCrateDecl(decl)
+                            }
                         }
                     }
                     ast::NameLike::Name(name) => match NameClass::classify(sema, &name)? {
diff --git a/src/tools/rust-analyzer/crates/ide/src/rename.rs b/src/tools/rust-analyzer/crates/ide/src/rename.rs
index e10c46381..dae8e71e8 100644
--- a/src/tools/rust-analyzer/crates/ide/src/rename.rs
+++ b/src/tools/rust-analyzer/crates/ide/src/rename.rs
@@ -145,7 +145,14 @@ fn find_definitions(
                     if name
                         .syntax()
                         .parent()
-                        .map_or(false, |it| ast::Rename::can_cast(it.kind())) =>
+                        .map_or(false, |it| ast::Rename::can_cast(it.kind()))
+                        // FIXME: uncomment this once we resolve to usages to extern crate declarations
+                        // && name
+                        //     .syntax()
+                        //     .ancestors()
+                        //     .nth(2)
+                        //     .map_or(true, |it| !ast::ExternCrate::can_cast(it.kind()))
+                        =>
                 {
                     bail!("Renaming aliases is currently unsupported")
                 }
@@ -165,7 +172,12 @@ fn find_definitions(
                             NameRefClass::FieldShorthand { local_ref, field_ref: _ } => {
                                 Definition::Local(local_ref)
                             }
+                            NameRefClass::ExternCrateShorthand { decl, .. } => {
+                                Definition::ExternCrateDecl(decl)
+                            }
                         })
+                        // FIXME: uncomment this once we resolve to usages to extern crate declarations
+                        .filter(|def| !matches!(def, Definition::ExternCrateDecl(..)))
                         .ok_or_else(|| format_err!("No references found at position"))
                         .and_then(|def| {
                             // if the name differs from the definitions name it has to be an alias
@@ -367,7 +379,7 @@ mod tests {
                 let mut file_id: Option<FileId> = None;
                 for edit in source_change.source_file_edits {
                     file_id = Some(edit.0);
-                    for indel in edit.1.into_iter() {
+                    for indel in edit.1 .0.into_iter() {
                         text_edit_builder.replace(indel.delete, indel.insert);
                     }
                 }
@@ -895,14 +907,17 @@ mod foo$0;
                     source_file_edits: {
                         FileId(
                             1,
-                        ): TextEdit {
-                            indels: [
-                                Indel {
-                                    insert: "foo2",
-                                    delete: 4..7,
-                                },
-                            ],
-                        },
+                        ): (
+                            TextEdit {
+                                indels: [
+                                    Indel {
+                                        insert: "foo2",
+                                        delete: 4..7,
+                                    },
+                                ],
+                            },
+                            None,
+                        ),
                     },
                     file_system_edits: [
                         MoveFile {
@@ -944,24 +959,30 @@ use crate::foo$0::FooContent;
                     source_file_edits: {
                         FileId(
                             0,
-                        ): TextEdit {
-                            indels: [
-                                Indel {
-                                    insert: "quux",
-                                    delete: 8..11,
-                                },
-                            ],
-                        },
+                        ): (
+                            TextEdit {
+                                indels: [
+                                    Indel {
+                                        insert: "quux",
+                                        delete: 8..11,
+                                    },
+                                ],
+                            },
+                            None,
+                        ),
                         FileId(
                             2,
-                        ): TextEdit {
-                            indels: [
-                                Indel {
-                                    insert: "quux",
-                                    delete: 11..14,
-                                },
-                            ],
-                        },
+                        ): (
+                            TextEdit {
+                                indels: [
+                                    Indel {
+                                        insert: "quux",
+                                        delete: 11..14,
+                                    },
+                                ],
+                            },
+                            None,
+                        ),
                     },
                     file_system_edits: [
                         MoveFile {
@@ -997,14 +1018,17 @@ mod fo$0o;
                     source_file_edits: {
                         FileId(
                             0,
-                        ): TextEdit {
-                            indels: [
-                                Indel {
-                                    insert: "foo2",
-                                    delete: 4..7,
-                                },
-                            ],
-                        },
+                        ): (
+                            TextEdit {
+                                indels: [
+                                    Indel {
+                                        insert: "foo2",
+                                        delete: 4..7,
+                                    },
+                                ],
+                            },
+                            None,
+                        ),
                     },
                     file_system_edits: [
                         MoveDir {
@@ -1047,14 +1071,17 @@ mod outer { mod fo$0o; }
                     source_file_edits: {
                         FileId(
                             0,
-                        ): TextEdit {
-                            indels: [
-                                Indel {
-                                    insert: "bar",
-                                    delete: 16..19,
-                                },
-                            ],
-                        },
+                        ): (
+                            TextEdit {
+                                indels: [
+                                    Indel {
+                                        insert: "bar",
+                                        delete: 16..19,
+                                    },
+                                ],
+                            },
+                            None,
+                        ),
                     },
                     file_system_edits: [
                         MoveFile {
@@ -1120,24 +1147,30 @@ pub mod foo$0;
                     source_file_edits: {
                         FileId(
                             0,
-                        ): TextEdit {
-                            indels: [
-                                Indel {
-                                    insert: "foo2",
-                                    delete: 27..30,
-                                },
-                            ],
-                        },
+                        ): (
+                            TextEdit {
+                                indels: [
+                                    Indel {
+                                        insert: "foo2",
+                                        delete: 27..30,
+                                    },
+                                ],
+                            },
+                            None,
+                        ),
                         FileId(
                             1,
-                        ): TextEdit {
-                            indels: [
-                                Indel {
-                                    insert: "foo2",
-                                    delete: 8..11,
-                                },
-                            ],
-                        },
+                        ): (
+                            TextEdit {
+                                indels: [
+                                    Indel {
+                                        insert: "foo2",
+                                        delete: 8..11,
+                                    },
+                                ],
+                            },
+                            None,
+                        ),
                     },
                     file_system_edits: [
                         MoveFile {
@@ -1187,14 +1220,17 @@ mod quux;
                     source_file_edits: {
                         FileId(
                             0,
-                        ): TextEdit {
-                            indels: [
-                                Indel {
-                                    insert: "foo2",
-                                    delete: 4..7,
-                                },
-                            ],
-                        },
+                        ): (
+                            TextEdit {
+                                indels: [
+                                    Indel {
+                                        insert: "foo2",
+                                        delete: 4..7,
+                                    },
+                                ],
+                            },
+                            None,
+                        ),
                     },
                     file_system_edits: [
                         MoveFile {
@@ -1325,18 +1361,21 @@ pub fn baz() {}
                     source_file_edits: {
                         FileId(
                             0,
-                        ): TextEdit {
-                            indels: [
-                                Indel {
-                                    insert: "r#fn",
-                                    delete: 4..7,
-                                },
-                                Indel {
-                                    insert: "r#fn",
-                                    delete: 22..25,
-                                },
-                            ],
-                        },
+                        ): (
+                            TextEdit {
+                                indels: [
+                                    Indel {
+                                        insert: "r#fn",
+                                        delete: 4..7,
+                                    },
+                                    Indel {
+                                        insert: "r#fn",
+                                        delete: 22..25,
+                                    },
+                                ],
+                            },
+                            None,
+                        ),
                     },
                     file_system_edits: [
                         MoveFile {
@@ -1395,18 +1434,21 @@ pub fn baz() {}
                     source_file_edits: {
                         FileId(
                             0,
-                        ): TextEdit {
-                            indels: [
-                                Indel {
-                                    insert: "foo",
-                                    delete: 4..8,
-                                },
-                                Indel {
-                                    insert: "foo",
-                                    delete: 23..27,
-                                },
-                            ],
-                        },
+                        ): (
+                            TextEdit {
+                                indels: [
+                                    Indel {
+                                        insert: "foo",
+                                        delete: 4..8,
+                                    },
+                                    Indel {
+                                        insert: "foo",
+                                        delete: 23..27,
+                                    },
+                                ],
+                            },
+                            None,
+                        ),
                     },
                     file_system_edits: [
                         MoveFile {
@@ -2487,4 +2529,109 @@ fn main() {
 ",
         )
     }
+
+    #[test]
+    fn extern_crate() {
+        check_prepare(
+            r"
+//- /lib.rs crate:main deps:foo
+extern crate foo$0;
+use foo as qux;
+//- /foo.rs crate:foo
+",
+            expect![[r#"No references found at position"#]],
+        );
+        // FIXME: replace above check_prepare with this once we resolve to usages to extern crate declarations
+        //         check(
+        //             "bar",
+        //             r"
+        // //- /lib.rs crate:main deps:foo
+        // extern crate foo$0;
+        // use foo as qux;
+        // //- /foo.rs crate:foo
+        // ",
+        //             r"
+        // extern crate foo as bar;
+        // use bar as qux;
+        // ",
+        //         );
+    }
+
+    #[test]
+    fn extern_crate_rename() {
+        check_prepare(
+            r"
+//- /lib.rs crate:main deps:foo
+extern crate foo as qux$0;
+use qux as frob;
+//- /foo.rs crate:foo
+",
+            expect!["Renaming aliases is currently unsupported"],
+        );
+        // FIXME: replace above check_prepare with this once we resolve to usages to extern crate
+        // declarations
+        //         check(
+        //             "bar",
+        //             r"
+        // //- /lib.rs crate:main deps:foo
+        // extern crate foo as qux$0;
+        // use qux as frob;
+        // //- /foo.rs crate:foo
+        // ",
+        //             r"
+        // extern crate foo as bar;
+        // use bar as frob;
+        // ",
+        //         );
+    }
+
+    #[test]
+    fn extern_crate_self() {
+        check_prepare(
+            r"
+extern crate self$0;
+use self as qux;
+",
+            expect!["No references found at position"],
+        );
+        // FIXME: replace above check_prepare with this once we resolve to usages to extern crate declarations
+        //         check(
+        //             "bar",
+        //             r"
+        // extern crate self$0;
+        // use self as qux;
+        // ",
+        //             r"
+        // extern crate self as bar;
+        // use self as qux;
+        // ",
+        //         );
+    }
+
+    #[test]
+    fn extern_crate_self_rename() {
+        check_prepare(
+            r"
+//- /lib.rs crate:main deps:foo
+extern crate self as qux$0;
+use qux as frob;
+//- /foo.rs crate:foo
+",
+            expect!["Renaming aliases is currently unsupported"],
+        );
+        // FIXME: replace above check_prepare with this once we resolve to usages to extern crate declarations
+        //         check(
+        //             "bar",
+        //             r"
+        // //- /lib.rs crate:main deps:foo
+        // extern crate self as qux$0;
+        // use qux as frob;
+        // //- /foo.rs crate:foo
+        // ",
+        //             r"
+        // extern crate self as bar;
+        // use bar as frob;
+        // ",
+        //         );
+    }
 }
diff --git a/src/tools/rust-analyzer/crates/ide/src/runnables.rs b/src/tools/rust-analyzer/crates/ide/src/runnables.rs
index 27ad63d82..5f87a7855 100644
--- a/src/tools/rust-analyzer/crates/ide/src/runnables.rs
+++ b/src/tools/rust-analyzer/crates/ide/src/runnables.rs
@@ -2,7 +2,7 @@ use std::fmt;
 
 use ast::HasName;
 use cfg::CfgExpr;
-use hir::{AsAssocItem, HasAttrs, HasSource, Semantics};
+use hir::{db::HirDatabase, AsAssocItem, HasAttrs, HasSource, Semantics};
 use ide_assists::utils::test_related_attribute;
 use ide_db::{
     base_db::{FilePosition, FileRange},
@@ -14,7 +14,7 @@ use ide_db::{
 use itertools::Itertools;
 use stdx::{always, format_to};
 use syntax::{
-    ast::{self, AstNode, HasAttrs as _},
+    ast::{self, AstNode},
     SmolStr, SyntaxNode,
 };
 
@@ -232,7 +232,7 @@ fn find_related_tests(
     for def in defs {
         let defs = def
             .usages(sema)
-            .set_scope(search_scope.clone())
+            .set_scope(search_scope.as_ref())
             .all()
             .references
             .into_values()
@@ -307,10 +307,9 @@ pub(crate) fn runnable_fn(
     sema: &Semantics<'_, RootDatabase>,
     def: hir::Function,
 ) -> Option<Runnable> {
-    let func = def.source(sema.db)?;
     let name = def.name(sema.db).to_smol_str();
 
-    let root = def.module(sema.db).krate().root_module(sema.db);
+    let root = def.module(sema.db).krate().root_module();
 
     let kind = if name == "main" && def.module(sema.db) == root {
         RunnableKind::Bin
@@ -323,10 +322,10 @@ pub(crate) fn runnable_fn(
             canonical_path.map(TestId::Path).unwrap_or(TestId::Name(name))
         };
 
-        if test_related_attribute(&func.value).is_some() {
-            let attr = TestAttr::from_fn(&func.value);
+        if def.is_test(sema.db) {
+            let attr = TestAttr::from_fn(sema.db, def);
             RunnableKind::Test { test_id: test_id(), attr }
-        } else if func.value.has_atom_attr("bench") {
+        } else if def.is_bench(sema.db) {
             RunnableKind::Bench { test_id: test_id() }
         } else {
             return None;
@@ -335,7 +334,7 @@ pub(crate) fn runnable_fn(
 
     let nav = NavigationTarget::from_named(
         sema.db,
-        func.as_ref().map(|it| it as &dyn ast::HasName),
+        def.source(sema.db)?.as_ref().map(|it| it as &dyn ast::HasName),
         SymbolKind::Function,
     );
     let cfg = def.attrs(sema.db).cfg();
@@ -487,12 +486,8 @@ pub struct TestAttr {
 }
 
 impl TestAttr {
-    fn from_fn(fn_def: &ast::Fn) -> TestAttr {
-        let ignore = fn_def
-            .attrs()
-            .filter_map(|attr| attr.simple_name())
-            .any(|attribute_text| attribute_text == "ignore");
-        TestAttr { ignore }
+    fn from_fn(db: &dyn HirDatabase, fn_def: hir::Function) -> TestAttr {
+        TestAttr { ignore: fn_def.is_ignore(db) }
     }
 }
 
@@ -594,6 +589,9 @@ fn main() {}
 #[test]
 fn test_foo() {}
 
+#[::core::prelude::v1::test]
+fn test_full_path() {}
+
 #[test]
 #[ignore]
 fn test_foo() {}
@@ -605,7 +603,7 @@ mod not_a_root {
     fn main() {}
 }
 "#,
-            &[TestMod, Bin, Test, Test, Bench],
+            &[TestMod, Bin, Test, Test, Test, Bench],
             expect![[r#"
                 [
                     Runnable {
@@ -614,7 +612,7 @@ mod not_a_root {
                             file_id: FileId(
                                 0,
                             ),
-                            full_range: 0..137,
+                            full_range: 0..190,
                             name: "",
                             kind: Module,
                         },
@@ -664,8 +662,29 @@ mod not_a_root {
                             file_id: FileId(
                                 0,
                             ),
-                            full_range: 41..75,
-                            focus_range: 62..70,
+                            full_range: 41..92,
+                            focus_range: 73..87,
+                            name: "test_full_path",
+                            kind: Function,
+                        },
+                        kind: Test {
+                            test_id: Path(
+                                "test_full_path",
+                            ),
+                            attr: TestAttr {
+                                ignore: false,
+                            },
+                        },
+                        cfg: None,
+                    },
+                    Runnable {
+                        use_name_in_title: false,
+                        nav: NavigationTarget {
+                            file_id: FileId(
+                                0,
+                            ),
+                            full_range: 94..128,
+                            focus_range: 115..123,
                             name: "test_foo",
                             kind: Function,
                         },
@@ -685,8 +704,8 @@ mod not_a_root {
                             file_id: FileId(
                                 0,
                             ),
-                            full_range: 77..99,
-                            focus_range: 89..94,
+                            full_range: 130..152,
+                            focus_range: 142..147,
                             name: "bench",
                             kind: Function,
                         },
diff --git a/src/tools/rust-analyzer/crates/ide/src/ssr.rs b/src/tools/rust-analyzer/crates/ide/src/ssr.rs
index deaf3c9c4..d8d81869a 100644
--- a/src/tools/rust-analyzer/crates/ide/src/ssr.rs
+++ b/src/tools/rust-analyzer/crates/ide/src/ssr.rs
@@ -126,14 +126,17 @@ mod tests {
                         source_file_edits: {
                             FileId(
                                 0,
-                            ): TextEdit {
-                                indels: [
-                                    Indel {
-                                        insert: "3",
-                                        delete: 33..34,
-                                    },
-                                ],
-                            },
+                            ): (
+                                TextEdit {
+                                    indels: [
+                                        Indel {
+                                            insert: "3",
+                                            delete: 33..34,
+                                        },
+                                    ],
+                                },
+                                None,
+                            ),
                         },
                         file_system_edits: [],
                         is_snippet: false,
@@ -163,24 +166,30 @@ mod tests {
                         source_file_edits: {
                             FileId(
                                 0,
-                            ): TextEdit {
-                                indels: [
-                                    Indel {
-                                        insert: "3",
-                                        delete: 33..34,
-                                    },
-                                ],
-                            },
+                            ): (
+                                TextEdit {
+                                    indels: [
+                                        Indel {
+                                            insert: "3",
+                                            delete: 33..34,
+                                        },
+                                    ],
+                                },
+                                None,
+                            ),
                             FileId(
                                 1,
-                            ): TextEdit {
-                                indels: [
-                                    Indel {
-                                        insert: "3",
-                                        delete: 11..12,
-                                    },
-                                ],
-                            },
+                            ): (
+                                TextEdit {
+                                    indels: [
+                                        Indel {
+                                            insert: "3",
+                                            delete: 11..12,
+                                        },
+                                    ],
+                                },
+                                None,
+                            ),
                         },
                         file_system_edits: [],
                         is_snippet: false,
diff --git a/src/tools/rust-analyzer/crates/ide/src/static_index.rs b/src/tools/rust-analyzer/crates/ide/src/static_index.rs
index 3e3d9f8f8..d8696198d 100644
--- a/src/tools/rust-analyzer/crates/ide/src/static_index.rs
+++ b/src/tools/rust-analyzer/crates/ide/src/static_index.rs
@@ -3,13 +3,14 @@
 
 use std::collections::HashMap;
 
-use hir::{db::HirDatabase, Crate, Module, Semantics};
+use hir::{db::HirDatabase, Crate, Module};
+use ide_db::helpers::get_definition;
 use ide_db::{
     base_db::{FileId, FileRange, SourceDatabaseExt},
-    defs::{Definition, IdentClass},
+    defs::Definition,
     FxHashSet, RootDatabase,
 };
-use syntax::{AstNode, SyntaxKind::*, SyntaxToken, TextRange, T};
+use syntax::{AstNode, SyntaxKind::*, TextRange, T};
 
 use crate::{
     hover::hover_for_definition,
@@ -73,7 +74,7 @@ impl TokenStore {
     }
 
     pub fn iter(self) -> impl Iterator<Item = (TokenId, TokenStaticData)> {
-        self.0.into_iter().enumerate().map(|(i, x)| (TokenId(i), x))
+        self.0.into_iter().enumerate().map(|(id, data)| (TokenId(id), data))
     }
 }
 
@@ -87,7 +88,7 @@ pub struct StaticIndexedFile {
 
 fn all_modules(db: &dyn HirDatabase) -> Vec<Module> {
     let mut worklist: Vec<_> =
-        Crate::all(db).into_iter().map(|krate| krate.root_module(db)).collect();
+        Crate::all(db).into_iter().map(|krate| krate.root_module()).collect();
     let mut modules = Vec::new();
 
     while let Some(module) = worklist.pop() {
@@ -132,9 +133,9 @@ impl StaticIndex<'_> {
         // hovers
         let sema = hir::Semantics::new(self.db);
         let tokens_or_nodes = sema.parse(file_id).syntax().clone();
-        let tokens = tokens_or_nodes.descendants_with_tokens().filter_map(|x| match x {
+        let tokens = tokens_or_nodes.descendants_with_tokens().filter_map(|it| match it {
             syntax::NodeOrToken::Node(_) => None,
-            syntax::NodeOrToken::Token(x) => Some(x),
+            syntax::NodeOrToken::Token(it) => Some(it),
         });
         let hover_config = HoverConfig {
             links_in_hover: true,
@@ -154,28 +155,29 @@ impl StaticIndex<'_> {
             let range = token.text_range();
             let node = token.parent().unwrap();
             let def = match get_definition(&sema, token.clone()) {
-                Some(x) => x,
+                Some(it) => it,
                 None => continue,
             };
-            let id = if let Some(x) = self.def_map.get(&def) {
-                *x
+            let id = if let Some(it) = self.def_map.get(&def) {
+                *it
             } else {
-                let x = self.tokens.insert(TokenStaticData {
+                let it = self.tokens.insert(TokenStaticData {
                     hover: hover_for_definition(&sema, file_id, def, &node, &hover_config),
-                    definition: def
-                        .try_to_nav(self.db)
-                        .map(|x| FileRange { file_id: x.file_id, range: x.focus_or_full_range() }),
+                    definition: def.try_to_nav(self.db).map(|it| FileRange {
+                        file_id: it.file_id,
+                        range: it.focus_or_full_range(),
+                    }),
                     references: vec![],
                     moniker: current_crate.and_then(|cc| def_to_moniker(self.db, def, cc)),
                 });
-                self.def_map.insert(def, x);
-                x
+                self.def_map.insert(def, it);
+                it
             };
             let token = self.tokens.get_mut(id).unwrap();
             token.references.push(ReferenceData {
                 range: FileRange { range, file_id },
                 is_definition: match def.try_to_nav(self.db) {
-                    Some(x) => x.file_id == file_id && x.focus_or_full_range() == range,
+                    Some(it) => it.file_id == file_id && it.focus_or_full_range() == range,
                     None => false,
                 },
             });
@@ -187,7 +189,7 @@ impl StaticIndex<'_> {
     pub fn compute(analysis: &Analysis) -> StaticIndex<'_> {
         let db = &*analysis.db;
         let work = all_modules(db).into_iter().filter(|module| {
-            let file_id = module.definition_source(db).file_id.original_file(db);
+            let file_id = module.definition_source_file_id(db).original_file(db);
             let source_root = db.file_source_root(file_id);
             let source_root = db.source_root(source_root);
             !source_root.is_library
@@ -201,7 +203,7 @@ impl StaticIndex<'_> {
         };
         let mut visited_files = FxHashSet::default();
         for module in work {
-            let file_id = module.definition_source(db).file_id.original_file(db);
+            let file_id = module.definition_source_file_id(db).original_file(db);
             if visited_files.contains(&file_id) {
                 continue;
             }
@@ -213,16 +215,6 @@ impl StaticIndex<'_> {
     }
 }
 
-fn get_definition(sema: &Semantics<'_, RootDatabase>, token: SyntaxToken) -> Option<Definition> {
-    for token in sema.descend_into_macros(token) {
-        let def = IdentClass::classify_token(sema, &token).map(IdentClass::definitions_no_ops);
-        if let Some(&[x]) = def.as_deref() {
-            return Some(x);
-        }
-    }
-    None
-}
-
 #[cfg(test)]
 mod tests {
     use crate::{fixture, StaticIndex};
@@ -233,14 +225,14 @@ mod tests {
     fn check_all_ranges(ra_fixture: &str) {
         let (analysis, ranges) = fixture::annotations_without_marker(ra_fixture);
         let s = StaticIndex::compute(&analysis);
-        let mut range_set: HashSet<_> = ranges.iter().map(|x| x.0).collect();
+        let mut range_set: HashSet<_> = ranges.iter().map(|it| it.0).collect();
         for f in s.files {
             for (range, _) in f.tokens {
-                let x = FileRange { file_id: f.file_id, range };
-                if !range_set.contains(&x) {
-                    panic!("additional range {x:?}");
+                let it = FileRange { file_id: f.file_id, range };
+                if !range_set.contains(&it) {
+                    panic!("additional range {it:?}");
                 }
-                range_set.remove(&x);
+                range_set.remove(&it);
             }
         }
         if !range_set.is_empty() {
@@ -251,17 +243,17 @@ mod tests {
     fn check_definitions(ra_fixture: &str) {
         let (analysis, ranges) = fixture::annotations_without_marker(ra_fixture);
         let s = StaticIndex::compute(&analysis);
-        let mut range_set: HashSet<_> = ranges.iter().map(|x| x.0).collect();
+        let mut range_set: HashSet<_> = ranges.iter().map(|it| it.0).collect();
         for (_, t) in s.tokens.iter() {
-            if let Some(x) = t.definition {
-                if x.range.start() == TextSize::from(0) {
+            if let Some(t) = t.definition {
+                if t.range.start() == TextSize::from(0) {
                     // ignore definitions that are whole of file
                     continue;
                 }
-                if !range_set.contains(&x) {
-                    panic!("additional definition {x:?}");
+                if !range_set.contains(&t) {
+                    panic!("additional definition {t:?}");
                 }
-                range_set.remove(&x);
+                range_set.remove(&t);
             }
         }
         if !range_set.is_empty() {
diff --git a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting.rs b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting.rs
index dc06591ff..ae9723640 100644
--- a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting.rs
+++ b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting.rs
@@ -24,7 +24,7 @@ use syntax::{
 
 use crate::{
     syntax_highlighting::{
-        escape::{highlight_escape_char, highlight_escape_string},
+        escape::{highlight_escape_byte, highlight_escape_char, highlight_escape_string},
         format::highlight_format_string,
         highlights::Highlights,
         macro_::MacroHighlighter,
@@ -265,10 +265,14 @@ fn traverse(
 
         // set macro and attribute highlighting states
         match event.clone() {
-            Enter(NodeOrToken::Node(node)) if ast::TokenTree::can_cast(node.kind()) => {
+            Enter(NodeOrToken::Node(node))
+                if current_macro.is_none() && ast::TokenTree::can_cast(node.kind()) =>
+            {
                 tt_level += 1;
             }
-            Leave(NodeOrToken::Node(node)) if ast::TokenTree::can_cast(node.kind()) => {
+            Leave(NodeOrToken::Node(node))
+                if current_macro.is_none() && ast::TokenTree::can_cast(node.kind()) =>
+            {
                 tt_level -= 1;
             }
             Enter(NodeOrToken::Node(node)) if ast::Attr::can_cast(node.kind()) => {
@@ -387,7 +391,7 @@ fn traverse(
             };
         let descended_element = if in_macro {
             // Attempt to descend tokens into macro-calls.
-            match element {
+            let res = match element {
                 NodeOrToken::Token(token) if token.kind() != COMMENT => {
                     let token = match attr_or_derive_item {
                         Some(AttrOrDerive::Attr(_)) => {
@@ -412,7 +416,8 @@ fn traverse(
                     }
                 }
                 e => e,
-            }
+            };
+            res
         } else {
             element
         };
@@ -466,6 +471,14 @@ fn traverse(
                 };
 
                 highlight_escape_char(hl, &char, range.start())
+            } else if ast::Byte::can_cast(token.kind())
+                && ast::Byte::can_cast(descended_token.kind())
+            {
+                let Some(byte) = ast::Byte::cast(token) else {
+                    continue;
+                };
+
+                highlight_escape_byte(hl, &byte, range.start())
             }
         }
 
diff --git a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/escape.rs b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/escape.rs
index 211e35880..5913ca5e4 100644
--- a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/escape.rs
+++ b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/escape.rs
@@ -1,7 +1,7 @@
 //! Syntax highlighting for escape sequences
 use crate::syntax_highlighting::highlights::Highlights;
 use crate::{HlRange, HlTag};
-use syntax::ast::{Char, IsString};
+use syntax::ast::{Byte, Char, IsString};
 use syntax::{AstToken, TextRange, TextSize};
 
 pub(super) fn highlight_escape_string<T: IsString>(
@@ -10,14 +10,14 @@ pub(super) fn highlight_escape_string<T: IsString>(
     start: TextSize,
 ) {
     string.escaped_char_ranges(&mut |piece_range, char| {
-        if char.is_err() {
-            return;
-        }
-
         if string.text()[piece_range.start().into()..].starts_with('\\') {
+            let highlight = match char {
+                Ok(_) => HlTag::EscapeSequence,
+                Err(_) => HlTag::InvalidEscapeSequence,
+            };
             stack.add(HlRange {
                 range: piece_range + start,
-                highlight: HlTag::EscapeSequence.into(),
+                highlight: highlight.into(),
                 binding_hash: None,
             });
         }
@@ -26,6 +26,9 @@ pub(super) fn highlight_escape_string<T: IsString>(
 
 pub(super) fn highlight_escape_char(stack: &mut Highlights, char: &Char, start: TextSize) {
     if char.value().is_none() {
+        // We do not emit invalid escapes highlighting here. The lexer would likely be in a bad
+        // state and this token contains junks, since `'` is not a reliable delimiter (consider
+        // lifetimes). Nonetheless, parser errors should already be emitted.
         return;
     }
 
@@ -43,3 +46,24 @@ pub(super) fn highlight_escape_char(stack: &mut Highlights, char: &Char, start:
         TextRange::new(start + TextSize::from(1), start + TextSize::from(text.len() as u32 + 1));
     stack.add(HlRange { range, highlight: HlTag::EscapeSequence.into(), binding_hash: None })
 }
+
+pub(super) fn highlight_escape_byte(stack: &mut Highlights, byte: &Byte, start: TextSize) {
+    if byte.value().is_none() {
+        // See `highlight_escape_char` for why no error highlighting here.
+        return;
+    }
+
+    let text = byte.text();
+    if !text.starts_with("b'") || !text.ends_with('\'') {
+        return;
+    }
+
+    let text = &text[2..text.len() - 1];
+    if !text.starts_with('\\') {
+        return;
+    }
+
+    let range =
+        TextRange::new(start + TextSize::from(2), start + TextSize::from(text.len() as u32 + 2));
+    stack.add(HlRange { range, highlight: HlTag::EscapeSequence.into(), binding_hash: None })
+}
diff --git a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/highlight.rs b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/highlight.rs
index 3c40246a6..8e96bfa01 100644
--- a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/highlight.rs
+++ b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/highlight.rs
@@ -269,7 +269,26 @@ fn highlight_name_ref(
 
             h
         }
-        NameRefClass::FieldShorthand { .. } => SymbolKind::Field.into(),
+        NameRefClass::FieldShorthand { field_ref, .. } => {
+            highlight_def(sema, krate, field_ref.into())
+        }
+        NameRefClass::ExternCrateShorthand { decl, krate: resolved_krate } => {
+            let mut h = HlTag::Symbol(SymbolKind::Module).into();
+
+            if resolved_krate != krate {
+                h |= HlMod::Library
+            }
+            let is_public = decl.visibility(db) == hir::Visibility::Public;
+            if is_public {
+                h |= HlMod::Public
+            }
+            let is_from_builtin_crate = resolved_krate.is_builtin(db);
+            if is_from_builtin_crate {
+                h |= HlMod::DefaultLibrary;
+            }
+            h |= HlMod::CrateRoot;
+            h
+        }
     };
 
     h.tag = match name_ref.token_kind() {
@@ -474,6 +493,14 @@ fn highlight_def(
             }
             h
         }
+        Definition::ExternCrateDecl(extern_crate) => {
+            let mut highlight =
+                Highlight::new(HlTag::Symbol(SymbolKind::Module)) | HlMod::CrateRoot;
+            if extern_crate.alias(db).is_none() {
+                highlight |= HlMod::Library;
+            }
+            highlight
+        }
         Definition::Label(_) => Highlight::new(HlTag::Symbol(SymbolKind::Label)),
         Definition::BuiltinAttr(_) => Highlight::new(HlTag::Symbol(SymbolKind::BuiltinAttr)),
         Definition::ToolModule(_) => Highlight::new(HlTag::Symbol(SymbolKind::ToolModule)),
diff --git a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/html.rs b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/html.rs
index 2c7823069..bbc6b55a6 100644
--- a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/html.rs
+++ b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/html.rs
@@ -109,6 +109,7 @@ pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padd
 .control            { font-style: italic; }
 .reference          { font-style: italic; font-weight: bold; }
 
-.unresolved_reference { color: #FC5555; text-decoration: wavy underline; }
+.invalid_escape_sequence { color: #FC5555; text-decoration: wavy underline; }
+.unresolved_reference    { color: #FC5555; text-decoration: wavy underline; }
 </style>
 ";
diff --git a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/inject.rs b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/inject.rs
index 901df147d..2657a6414 100644
--- a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/inject.rs
+++ b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/inject.rs
@@ -288,7 +288,7 @@ fn find_doc_string_in_attr(attr: &hir::Attr, it: &ast::Attr) -> Option<ast::Stri
 
 fn module_def_to_hl_tag(def: Definition) -> HlTag {
     let symbol = match def {
-        Definition::Module(_) => SymbolKind::Module,
+        Definition::Module(_) | Definition::ExternCrateDecl(_) => SymbolKind::Module,
         Definition::Function(_) => SymbolKind::Function,
         Definition::Adt(hir::Adt::Struct(_)) => SymbolKind::Struct,
         Definition::Adt(hir::Adt::Enum(_)) => SymbolKind::Enum,
diff --git a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/tags.rs b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/tags.rs
index f98310911..6d4cdd0ef 100644
--- a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/tags.rs
+++ b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/tags.rs
@@ -29,6 +29,7 @@ pub enum HlTag {
     Comment,
     EscapeSequence,
     FormatSpecifier,
+    InvalidEscapeSequence,
     Keyword,
     NumericLiteral,
     Operator(HlOperator),
@@ -166,6 +167,7 @@ impl HlTag {
             HlTag::CharLiteral => "char_literal",
             HlTag::Comment => "comment",
             HlTag::EscapeSequence => "escape_sequence",
+            HlTag::InvalidEscapeSequence => "invalid_escape_sequence",
             HlTag::FormatSpecifier => "format_specifier",
             HlTag::Keyword => "keyword",
             HlTag::Punctuation(punct) => match punct {
diff --git a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_assoc_functions.html b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_assoc_functions.html
index 9ed65fbc8..4dcbfe4eb 100644
--- a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_assoc_functions.html
+++ b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_assoc_functions.html
@@ -40,7 +40,8 @@ pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padd
 .control            { font-style: italic; }
 .reference          { font-style: italic; font-weight: bold; }
 
-.unresolved_reference { color: #FC5555; text-decoration: wavy underline; }
+.invalid_escape_sequence { color: #FC5555; text-decoration: wavy underline; }
+.unresolved_reference    { color: #FC5555; text-decoration: wavy underline; }
 </style>
 <pre><code><span class="keyword">fn</span> <span class="function declaration">not_static</span><span class="parenthesis">(</span><span class="parenthesis">)</span> <span class="brace">{</span><span class="brace">}</span>
 
diff --git a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_attributes.html b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_attributes.html
index 567ab8ccc..bf5505caf 100644
--- a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_attributes.html
+++ b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_attributes.html
@@ -40,7 +40,8 @@ pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padd
 .control            { font-style: italic; }
 .reference          { font-style: italic; font-weight: bold; }
 
-.unresolved_reference { color: #FC5555; text-decoration: wavy underline; }
+.invalid_escape_sequence { color: #FC5555; text-decoration: wavy underline; }
+.unresolved_reference    { color: #FC5555; text-decoration: wavy underline; }
 </style>
 <pre><code><span class="attribute_bracket attribute">#</span><span class="attribute_bracket attribute">[</span><span class="builtin_attr attribute library">allow</span><span class="parenthesis attribute">(</span><span class="none attribute">dead_code</span><span class="parenthesis attribute">)</span><span class="attribute_bracket attribute">]</span>
 <span class="attribute_bracket attribute">#</span><span class="attribute_bracket attribute">[</span><span class="tool_module attribute library">rustfmt</span><span class="operator attribute">::</span><span class="tool_module attribute library">skip</span><span class="attribute_bracket attribute">]</span>
diff --git a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_crate_root.html b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_crate_root.html
index 1e4c06df7..0d1b3c1f1 100644
--- a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_crate_root.html
+++ b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_crate_root.html
@@ -40,7 +40,8 @@ pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padd
 .control            { font-style: italic; }
 .reference          { font-style: italic; font-weight: bold; }
 
-.unresolved_reference { color: #FC5555; text-decoration: wavy underline; }
+.invalid_escape_sequence { color: #FC5555; text-decoration: wavy underline; }
+.unresolved_reference    { color: #FC5555; text-decoration: wavy underline; }
 </style>
 <pre><code><span class="keyword">extern</span> <span class="keyword">crate</span> <span class="module crate_root library">foo</span><span class="semicolon">;</span>
 <span class="keyword">use</span> <span class="module crate_root default_library library">core</span><span class="operator">::</span><span class="module default_library library">iter</span><span class="semicolon">;</span>
diff --git a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_default_library.html b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_default_library.html
index 5d66f832d..dd1528ed0 100644
--- a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_default_library.html
+++ b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_default_library.html
@@ -40,7 +40,8 @@ pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padd
 .control            { font-style: italic; }
 .reference          { font-style: italic; font-weight: bold; }
 
-.unresolved_reference { color: #FC5555; text-decoration: wavy underline; }
+.invalid_escape_sequence { color: #FC5555; text-decoration: wavy underline; }
+.unresolved_reference    { color: #FC5555; text-decoration: wavy underline; }
 </style>
 <pre><code><span class="keyword">use</span> <span class="module crate_root default_library library">core</span><span class="operator">::</span><span class="module default_library library">iter</span><span class="semicolon">;</span>
 
diff --git a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_doctest.html b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_doctest.html
index 35f240d42..d5f92aa5d 100644
--- a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_doctest.html
+++ b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_doctest.html
@@ -40,7 +40,8 @@ pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padd
 .control            { font-style: italic; }
 .reference          { font-style: italic; font-weight: bold; }
 
-.unresolved_reference { color: #FC5555; text-decoration: wavy underline; }
+.invalid_escape_sequence { color: #FC5555; text-decoration: wavy underline; }
+.unresolved_reference    { color: #FC5555; text-decoration: wavy underline; }
 </style>
 <pre><code><span class="comment documentation">//! This is a module to test doc injection.</span>
 <span class="comment documentation">//! ```</span>
diff --git a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_extern_crate.html b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_extern_crate.html
index 87b9da46e..88a008796 100644
--- a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_extern_crate.html
+++ b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_extern_crate.html
@@ -40,8 +40,10 @@ pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padd
 .control            { font-style: italic; }
 .reference          { font-style: italic; font-weight: bold; }
 
-.unresolved_reference { color: #FC5555; text-decoration: wavy underline; }
+.invalid_escape_sequence { color: #FC5555; text-decoration: wavy underline; }
+.unresolved_reference    { color: #FC5555; text-decoration: wavy underline; }
 </style>
 <pre><code><span class="keyword">extern</span> <span class="keyword">crate</span> <span class="module crate_root default_library library">std</span><span class="semicolon">;</span>
-<span class="keyword">extern</span> <span class="keyword">crate</span> <span class="module crate_root default_library library">alloc</span> <span class="keyword">as</span> <span class="module crate_root default_library declaration library">abc</span><span class="semicolon">;</span>
+<span class="keyword">extern</span> <span class="keyword">crate</span> <span class="module crate_root default_library library">alloc</span> <span class="keyword">as</span> <span class="module crate_root declaration">abc</span><span class="semicolon">;</span>
+<span class="keyword">extern</span> <span class="keyword">crate</span> <span class="unresolved_reference">unresolved</span> <span class="keyword">as</span> <span class="module crate_root declaration">definitely_unresolved</span><span class="semicolon">;</span>
 </code></pre>
\ No newline at end of file
diff --git a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_general.html b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_general.html
index 6b049f379..bdeb09d2f 100644
--- a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_general.html
+++ b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_general.html
@@ -40,7 +40,8 @@ pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padd
 .control            { font-style: italic; }
 .reference          { font-style: italic; font-weight: bold; }
 
-.unresolved_reference { color: #FC5555; text-decoration: wavy underline; }
+.invalid_escape_sequence { color: #FC5555; text-decoration: wavy underline; }
+.unresolved_reference    { color: #FC5555; text-decoration: wavy underline; }
 </style>
 <pre><code><span class="keyword">use</span> <span class="module">inner</span><span class="operator">::</span><span class="brace">{</span><span class="self_keyword">self</span> <span class="keyword">as</span> <span class="module declaration">inner_mod</span><span class="brace">}</span><span class="semicolon">;</span>
 <span class="keyword">mod</span> <span class="module declaration">inner</span> <span class="brace">{</span><span class="brace">}</span>
diff --git a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_injection.html b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_injection.html
index d9c3db6fb..f9c33b8a6 100644
--- a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_injection.html
+++ b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_injection.html
@@ -40,7 +40,8 @@ pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padd
 .control            { font-style: italic; }
 .reference          { font-style: italic; font-weight: bold; }
 
-.unresolved_reference { color: #FC5555; text-decoration: wavy underline; }
+.invalid_escape_sequence { color: #FC5555; text-decoration: wavy underline; }
+.unresolved_reference    { color: #FC5555; text-decoration: wavy underline; }
 </style>
 <pre><code><span class="keyword">fn</span> <span class="function declaration">fixture</span><span class="parenthesis">(</span><span class="value_param declaration reference">ra_fixture</span><span class="colon">:</span> <span class="punctuation">&</span><span class="builtin_type">str</span><span class="parenthesis">)</span> <span class="brace">{</span><span class="brace">}</span>
 
diff --git a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_keywords.html b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_keywords.html
index 3900959be..2043752bc 100644
--- a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_keywords.html
+++ b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_keywords.html
@@ -40,9 +40,10 @@ pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padd
 .control            { font-style: italic; }
 .reference          { font-style: italic; font-weight: bold; }
 
-.unresolved_reference { color: #FC5555; text-decoration: wavy underline; }
+.invalid_escape_sequence { color: #FC5555; text-decoration: wavy underline; }
+.unresolved_reference    { color: #FC5555; text-decoration: wavy underline; }
 </style>
-<pre><code><span class="keyword">extern</span> <span class="keyword">crate</span> <span class="self_keyword crate_root public">self</span><span class="semicolon">;</span>
+<pre><code><span class="keyword">extern</span> <span class="keyword">crate</span> <span class="self_keyword crate_root">self</span><span class="semicolon">;</span>
 
 <span class="keyword">use</span> <span class="keyword crate_root public">crate</span><span class="semicolon">;</span>
 <span class="keyword">use</span> <span class="self_keyword crate_root public">self</span><span class="semicolon">;</span>
diff --git a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_lifetimes.html b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_lifetimes.html
index f98e0b1cd..ec39998de 100644
--- a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_lifetimes.html
+++ b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_lifetimes.html
@@ -40,7 +40,8 @@ pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padd
 .control            { font-style: italic; }
 .reference          { font-style: italic; font-weight: bold; }
 
-.unresolved_reference { color: #FC5555; text-decoration: wavy underline; }
+.invalid_escape_sequence { color: #FC5555; text-decoration: wavy underline; }
+.unresolved_reference    { color: #FC5555; text-decoration: wavy underline; }
 </style>
 <pre><code>
 <span class="attribute_bracket attribute">#</span><span class="attribute_bracket attribute">[</span><span class="attribute attribute default_library library">derive</span><span class="parenthesis attribute">(</span><span class="parenthesis attribute">)</span><span class="attribute_bracket attribute">]</span>
diff --git a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_macros.html b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_macros.html
index 2cbbf6964..06b66b302 100644
--- a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_macros.html
+++ b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_macros.html
@@ -40,7 +40,8 @@ pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padd
 .control            { font-style: italic; }
 .reference          { font-style: italic; font-weight: bold; }
 
-.unresolved_reference { color: #FC5555; text-decoration: wavy underline; }
+.invalid_escape_sequence { color: #FC5555; text-decoration: wavy underline; }
+.unresolved_reference    { color: #FC5555; text-decoration: wavy underline; }
 </style>
 <pre><code><span class="module crate_root library">proc_macros</span><span class="operator">::</span><span class="macro library">mirror</span><span class="macro_bang">!</span> <span class="brace macro">{</span>
     <span class="brace macro">{</span>
@@ -89,8 +90,18 @@ pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padd
     <span class="brace">}</span>
 <span class="brace">}</span>
 
+<span class="attribute_bracket attribute">#</span><span class="attribute_bracket attribute">[</span><span class="builtin_attr attribute library">rustc_builtin_macro</span><span class="attribute_bracket attribute">]</span>
+<span class="keyword">macro_rules</span><span class="macro_bang">!</span> <span class="macro declaration">concat</span> <span class="brace">{</span><span class="brace">}</span>
+<span class="attribute_bracket attribute">#</span><span class="attribute_bracket attribute">[</span><span class="builtin_attr attribute library">rustc_builtin_macro</span><span class="attribute_bracket attribute">]</span>
+<span class="keyword">macro_rules</span><span class="macro_bang">!</span> <span class="macro declaration">include</span> <span class="brace">{</span><span class="brace">}</span>
+<span class="attribute_bracket attribute">#</span><span class="attribute_bracket attribute">[</span><span class="builtin_attr attribute library">rustc_builtin_macro</span><span class="attribute_bracket attribute">]</span>
+<span class="keyword">macro_rules</span><span class="macro_bang">!</span> <span class="macro declaration">format_args</span> <span class="brace">{</span><span class="brace">}</span>
+
+<span class="macro">include</span><span class="macro_bang">!</span><span class="parenthesis macro">(</span><span class="none macro">concat</span><span class="punctuation macro">!</span><span class="parenthesis macro">(</span><span class="string_literal macro">"foo/"</span><span class="comma macro">,</span> <span class="string_literal macro">"foo.rs"</span><span class="parenthesis macro">)</span><span class="parenthesis macro">)</span><span class="semicolon">;</span>
+
 <span class="keyword">fn</span> <span class="function declaration">main</span><span class="parenthesis">(</span><span class="parenthesis">)</span> <span class="brace">{</span>
-    <span class="unresolved_reference">println</span><span class="macro_bang">!</span><span class="parenthesis macro">(</span><span class="string_literal macro">"Hello, {}!"</span><span class="comma macro">,</span> <span class="numeric_literal macro">92</span><span class="parenthesis macro">)</span><span class="semicolon">;</span>
+    <span class="macro">format_args</span><span class="macro_bang">!</span><span class="parenthesis macro">(</span><span class="string_literal macro">"Hello, </span><span class="format_specifier">{</span><span class="format_specifier">}</span><span class="string_literal macro">!"</span><span class="comma macro">,</span> <span class="numeric_literal macro">92</span><span class="parenthesis macro">)</span><span class="semicolon">;</span>
     <span class="macro">dont_color_me_braces</span><span class="macro_bang">!</span><span class="parenthesis macro">(</span><span class="parenthesis macro">)</span><span class="semicolon">;</span>
     <span class="macro">noop</span><span class="macro_bang">!</span><span class="parenthesis macro">(</span><span class="macro macro">noop</span><span class="macro_bang macro">!</span><span class="parenthesis macro">(</span><span class="numeric_literal macro">1</span><span class="parenthesis macro">)</span><span class="parenthesis macro">)</span><span class="semicolon">;</span>
-<span class="brace">}</span></code></pre>
\ No newline at end of file
+<span class="brace">}</span>
+</code></pre>
\ No newline at end of file
diff --git a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_module_docs_inline.html b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_module_docs_inline.html
index 8a1d69816..4dcf8e5f0 100644
--- a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_module_docs_inline.html
+++ b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_module_docs_inline.html
@@ -40,7 +40,8 @@ pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padd
 .control            { font-style: italic; }
 .reference          { font-style: italic; font-weight: bold; }
 
-.unresolved_reference { color: #FC5555; text-decoration: wavy underline; }
+.invalid_escape_sequence { color: #FC5555; text-decoration: wavy underline; }
+.unresolved_reference    { color: #FC5555; text-decoration: wavy underline; }
 </style>
 <pre><code><span class="comment documentation">//! </span><span class="struct documentation injected intra_doc_link">[Struct]</span>
 <span class="comment documentation">//! This is an intra doc injection test for modules</span>
diff --git a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_module_docs_outline.html b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_module_docs_outline.html
index c4c3e3dc2..084bbf2f7 100644
--- a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_module_docs_outline.html
+++ b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_module_docs_outline.html
@@ -40,7 +40,8 @@ pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padd
 .control            { font-style: italic; }
 .reference          { font-style: italic; font-weight: bold; }
 
-.unresolved_reference { color: #FC5555; text-decoration: wavy underline; }
+.invalid_escape_sequence { color: #FC5555; text-decoration: wavy underline; }
+.unresolved_reference    { color: #FC5555; text-decoration: wavy underline; }
 </style>
 <pre><code><span class="comment documentation">/// </span><span class="struct documentation injected intra_doc_link">[crate::foo::Struct]</span>
 <span class="comment documentation">/// This is an intra doc injection test for modules</span>
diff --git a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_operators.html b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_operators.html
index 2369071ae..1af4bcfbd 100644
--- a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_operators.html
+++ b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_operators.html
@@ -40,7 +40,8 @@ pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padd
 .control            { font-style: italic; }
 .reference          { font-style: italic; font-weight: bold; }
 
-.unresolved_reference { color: #FC5555; text-decoration: wavy underline; }
+.invalid_escape_sequence { color: #FC5555; text-decoration: wavy underline; }
+.unresolved_reference    { color: #FC5555; text-decoration: wavy underline; }
 </style>
 <pre><code><span class="keyword">fn</span> <span class="function declaration">main</span><span class="parenthesis">(</span><span class="parenthesis">)</span> <span class="brace">{</span>
     <span class="numeric_literal">1</span> <span class="arithmetic">+</span> <span class="numeric_literal">1</span> <span class="arithmetic">-</span> <span class="numeric_literal">1</span> <span class="arithmetic">*</span> <span class="numeric_literal">1</span> <span class="arithmetic">/</span> <span class="numeric_literal">1</span> <span class="arithmetic">%</span> <span class="numeric_literal">1</span> <span class="bitwise">|</span> <span class="numeric_literal">1</span> <span class="bitwise">&</span> <span class="numeric_literal">1</span> <span class="logical">!</span> <span class="numeric_literal">1</span> <span class="bitwise">^</span> <span class="numeric_literal">1</span> <span class="bitwise">&gt;&gt;</span> <span class="numeric_literal">1</span> <span class="bitwise">&lt;&lt;</span> <span class="numeric_literal">1</span><span class="semicolon">;</span>
diff --git a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_rainbow.html b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_rainbow.html
index bff35c897..ec18c3ea1 100644
--- a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_rainbow.html
+++ b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_rainbow.html
@@ -40,7 +40,8 @@ pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padd
 .control            { font-style: italic; }
 .reference          { font-style: italic; font-weight: bold; }
 
-.unresolved_reference { color: #FC5555; text-decoration: wavy underline; }
+.invalid_escape_sequence { color: #FC5555; text-decoration: wavy underline; }
+.unresolved_reference    { color: #FC5555; text-decoration: wavy underline; }
 </style>
 <pre><code><span class="keyword">fn</span> <span class="function declaration">main</span><span class="parenthesis">(</span><span class="parenthesis">)</span> <span class="brace">{</span>
     <span class="keyword">let</span> <span class="variable declaration reference" data-binding-hash="8121853618659664005" style="color: hsl(273,88%,88%);">hello</span> <span class="operator">=</span> <span class="string_literal">"hello"</span><span class="semicolon">;</span>
diff --git a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_strings.html b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_strings.html
index fa374b04f..3ac8aa9cc 100644
--- a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_strings.html
+++ b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_strings.html
@@ -40,7 +40,8 @@ pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padd
 .control            { font-style: italic; }
 .reference          { font-style: italic; font-weight: bold; }
 
-.unresolved_reference { color: #FC5555; text-decoration: wavy underline; }
+.invalid_escape_sequence { color: #FC5555; text-decoration: wavy underline; }
+.unresolved_reference    { color: #FC5555; text-decoration: wavy underline; }
 </style>
 <pre><code><span class="keyword">macro_rules</span><span class="macro_bang">!</span> <span class="macro declaration">println</span> <span class="brace">{</span>
     <span class="parenthesis">(</span><span class="punctuation">$</span><span class="parenthesis">(</span><span class="punctuation">$</span>arg<span class="colon">:</span>tt<span class="parenthesis">)</span><span class="punctuation">*</span><span class="parenthesis">)</span> <span class="operator">=</span><span class="angle">&gt;</span> <span class="parenthesis">(</span><span class="brace">{</span>
@@ -105,6 +106,8 @@ pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padd
     <span class="keyword">let</span> <span class="variable declaration">a</span> <span class="operator">=</span> <span class="char_literal">'</span><span class="escape_sequence">\x65</span><span class="char_literal">'</span><span class="semicolon">;</span>
     <span class="keyword">let</span> <span class="variable declaration">a</span> <span class="operator">=</span> <span class="char_literal">'</span><span class="escape_sequence">\x00</span><span class="char_literal">'</span><span class="semicolon">;</span>
 
+    <span class="keyword">let</span> <span class="variable declaration">a</span> <span class="operator">=</span> <span class="byte_literal">b'</span><span class="escape_sequence">\xFF</span><span class="byte_literal">'</span><span class="semicolon">;</span>
+
     <span class="macro">println</span><span class="macro_bang">!</span><span class="parenthesis macro">(</span><span class="string_literal macro">"Hello </span><span class="escape_sequence">{{</span><span class="string_literal macro">Hello</span><span class="escape_sequence">}}</span><span class="string_literal macro">"</span><span class="parenthesis macro">)</span><span class="semicolon">;</span>
     <span class="comment">// from https://doc.rust-lang.org/std/fmt/index.html</span>
     <span class="macro">println</span><span class="macro_bang">!</span><span class="parenthesis macro">(</span><span class="string_literal macro">"Hello"</span><span class="parenthesis macro">)</span><span class="semicolon">;</span>                 <span class="comment">// =&gt; "Hello"</span>
@@ -159,9 +162,10 @@ pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padd
     <span class="macro">println</span><span class="macro_bang">!</span><span class="parenthesis macro">(</span><span class="string_literal macro">"Hello</span><span class="escape_sequence">\n</span><span class="string_literal macro">World"</span><span class="parenthesis macro">)</span><span class="semicolon">;</span>
     <span class="macro">println</span><span class="macro_bang">!</span><span class="parenthesis macro">(</span><span class="string_literal macro">"</span><span class="escape_sequence">\u{48}</span><span class="escape_sequence">\x65</span><span class="escape_sequence">\x6C</span><span class="escape_sequence">\x6C</span><span class="escape_sequence">\x6F</span><span class="string_literal macro"> World"</span><span class="parenthesis macro">)</span><span class="semicolon">;</span>
 
-    <span class="keyword">let</span> <span class="punctuation">_</span> <span class="operator">=</span> <span class="string_literal">"</span><span class="escape_sequence">\x28</span><span class="escape_sequence">\x28</span><span class="escape_sequence">\x00</span><span class="escape_sequence">\x63</span><span class="escape_sequence">\n</span><span class="string_literal">"</span><span class="semicolon">;</span>
-    <span class="keyword">let</span> <span class="punctuation">_</span> <span class="operator">=</span> <span class="string_literal">b"</span><span class="escape_sequence">\x28</span><span class="escape_sequence">\x28</span><span class="escape_sequence">\x00</span><span class="escape_sequence">\x63</span><span class="escape_sequence">\n</span><span class="string_literal">"</span><span class="semicolon">;</span>
-    <span class="keyword">let</span> <span class="punctuation">_</span> <span class="operator">=</span> <span class="string_literal">r"\\"</span><span class="semicolon">;</span>
+    <span class="keyword">let</span> <span class="punctuation">_</span> <span class="operator">=</span> <span class="string_literal">"</span><span class="escape_sequence">\x28</span><span class="escape_sequence">\x28</span><span class="escape_sequence">\x00</span><span class="escape_sequence">\x63</span><span class="invalid_escape_sequence">\xFF</span><span class="escape_sequence">\u{FF}</span><span class="escape_sequence">\n</span><span class="string_literal">"</span><span class="semicolon">;</span> <span class="comment">// invalid non-UTF8 escape sequences</span>
+    <span class="keyword">let</span> <span class="punctuation">_</span> <span class="operator">=</span> <span class="string_literal">b"</span><span class="escape_sequence">\x28</span><span class="escape_sequence">\x28</span><span class="escape_sequence">\x00</span><span class="escape_sequence">\x63</span><span class="escape_sequence">\xFF</span><span class="invalid_escape_sequence">\u{FF}</span><span class="escape_sequence">\n</span><span class="string_literal">"</span><span class="semicolon">;</span> <span class="comment">// valid bytes, invalid unicodes</span>
+    <span class="keyword">let</span> <span class="punctuation">_</span> <span class="operator">=</span> <span class="string_literal">c"</span><span class="escape_sequence">\u{FF}</span><span class="escape_sequence">\xFF</span><span class="string_literal">"</span><span class="semicolon">;</span> <span class="comment">// valid bytes, valid unicodes</span>
+    <span class="keyword">let</span> <span class="variable declaration reference">backslash</span> <span class="operator">=</span> <span class="string_literal">r"\\"</span><span class="semicolon">;</span>
 
     <span class="macro">println</span><span class="macro_bang">!</span><span class="parenthesis macro">(</span><span class="string_literal macro">"</span><span class="format_specifier">{</span><span class="escape_sequence">\x41</span><span class="format_specifier">}</span><span class="string_literal macro">"</span><span class="comma macro">,</span> <span class="none macro">A</span> <span class="operator macro">=</span> <span class="numeric_literal macro">92</span><span class="parenthesis macro">)</span><span class="semicolon">;</span>
     <span class="macro">println</span><span class="macro_bang">!</span><span class="parenthesis macro">(</span><span class="string_literal macro">"</span><span class="format_specifier">{</span><span class="variable">ничоси</span><span class="format_specifier">}</span><span class="string_literal macro">"</span><span class="comma macro">,</span> <span class="none macro">ничоси</span> <span class="operator macro">=</span> <span class="numeric_literal macro">92</span><span class="parenthesis macro">)</span><span class="semicolon">;</span>
@@ -173,6 +177,6 @@ pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padd
     <span class="macro">assert</span><span class="macro_bang">!</span><span class="parenthesis macro">(</span><span class="bool_literal macro">true</span><span class="comma macro">,</span> <span class="string_literal macro">"</span><span class="format_specifier">{</span><span class="format_specifier">}</span><span class="string_literal macro"> asdasd"</span><span class="comma macro">,</span> <span class="numeric_literal macro">1</span><span class="parenthesis macro">)</span><span class="semicolon">;</span>
     <span class="macro">toho</span><span class="macro_bang">!</span><span class="parenthesis macro">(</span><span class="string_literal macro">"</span><span class="format_specifier">{</span><span class="format_specifier">}</span><span class="string_literal macro">fmt"</span><span class="comma macro">,</span> <span class="numeric_literal macro">0</span><span class="parenthesis macro">)</span><span class="semicolon">;</span>
     <span class="macro unsafe">asm</span><span class="macro_bang">!</span><span class="parenthesis macro">(</span><span class="string_literal macro">"mov eax, </span><span class="format_specifier">{</span><span class="numeric_literal">0</span><span class="format_specifier">}</span><span class="string_literal macro">"</span><span class="parenthesis macro">)</span><span class="semicolon">;</span>
-    <span class="macro">format_args</span><span class="macro_bang">!</span><span class="parenthesis macro">(</span><span class="none macro">concat</span><span class="punctuation macro">!</span><span class="parenthesis macro">(</span><span class="string_literal macro">"</span><span class="format_specifier">{</span><span class="format_specifier">}</span><span class="string_literal macro">"</span><span class="parenthesis macro">)</span><span class="comma macro">,</span> <span class="string_literal macro">"</span><span class="format_specifier">{</span><span class="format_specifier">}</span><span class="string_literal macro">"</span><span class="parenthesis macro">)</span><span class="semicolon">;</span>
-    <span class="macro">format_args</span><span class="macro_bang">!</span><span class="parenthesis macro">(</span><span class="string_literal macro">"</span><span class="format_specifier">{</span><span class="format_specifier">}</span><span class="string_literal macro">"</span><span class="comma macro">,</span> <span class="none macro">format_args</span><span class="operator macro">!</span><span class="parenthesis macro">(</span><span class="string_literal macro">"</span><span class="format_specifier">{</span><span class="format_specifier">}</span><span class="string_literal macro">"</span><span class="comma macro">,</span> <span class="numeric_literal macro">0</span><span class="parenthesis macro">)</span><span class="parenthesis macro">)</span><span class="semicolon">;</span>
+    <span class="macro">format_args</span><span class="macro_bang">!</span><span class="parenthesis macro">(</span><span class="none macro">concat</span><span class="punctuation macro">!</span><span class="parenthesis macro">(</span><span class="string_literal macro">"</span><span class="format_specifier">{</span><span class="format_specifier">}</span><span class="string_literal macro">"</span><span class="parenthesis macro">)</span><span class="comma macro">,</span> <span class="string_literal macro">"{}"</span><span class="parenthesis macro">)</span><span class="semicolon">;</span>
+    <span class="macro">format_args</span><span class="macro_bang">!</span><span class="parenthesis macro">(</span><span class="string_literal macro">"</span><span class="format_specifier">{</span><span class="format_specifier">}</span><span class="string_literal macro"> </span><span class="format_specifier">{</span><span class="format_specifier">}</span><span class="string_literal macro"> </span><span class="format_specifier">{</span><span class="format_specifier">}</span><span class="string_literal macro"> </span><span class="format_specifier">{</span><span class="format_specifier">}</span><span class="string_literal macro"> </span><span class="format_specifier">{</span><span class="format_specifier">}</span><span class="string_literal macro"> </span><span class="format_specifier">{</span><span class="format_specifier">}</span><span class="string_literal macro">"</span><span class="comma macro">,</span> <span class="variable macro reference">backslash</span><span class="comma macro">,</span> <span class="none macro">format_args</span><span class="punctuation macro">!</span><span class="parenthesis macro">(</span><span class="string_literal macro">"</span><span class="format_specifier">{</span><span class="format_specifier">}</span><span class="string_literal macro">"</span><span class="comma macro">,</span> <span class="numeric_literal macro">0</span><span class="parenthesis macro">)</span><span class="comma macro">,</span> <span class="unresolved_reference macro">foo</span><span class="comma macro">,</span> <span class="string_literal macro">"bar"</span><span class="comma macro">,</span> <span class="none macro">toho</span><span class="punctuation macro">!</span><span class="parenthesis macro">(</span><span class="parenthesis macro">)</span><span class="comma macro">,</span> <span class="variable macro reference">backslash</span><span class="parenthesis macro">)</span><span class="semicolon">;</span>
 <span class="brace">}</span></code></pre>
\ No newline at end of file
diff --git a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_unsafe.html b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_unsafe.html
index 654d51b8a..c72ea54e9 100644
--- a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_unsafe.html
+++ b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/test_data/highlight_unsafe.html
@@ -40,7 +40,8 @@ pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padd
 .control            { font-style: italic; }
 .reference          { font-style: italic; font-weight: bold; }
 
-.unresolved_reference { color: #FC5555; text-decoration: wavy underline; }
+.invalid_escape_sequence { color: #FC5555; text-decoration: wavy underline; }
+.unresolved_reference    { color: #FC5555; text-decoration: wavy underline; }
 </style>
 <pre><code><span class="keyword">macro_rules</span><span class="macro_bang">!</span> <span class="macro declaration">id</span> <span class="brace">{</span>
     <span class="parenthesis">(</span><span class="punctuation">$</span><span class="parenthesis">(</span><span class="punctuation">$</span>tt<span class="colon">:</span>tt<span class="parenthesis">)</span><span class="punctuation">*</span><span class="parenthesis">)</span> <span class="operator">=</span><span class="angle">&gt;</span> <span class="brace">{</span>
diff --git a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/tests.rs b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/tests.rs
index 497992f68..8749d355c 100644
--- a/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/tests.rs
+++ b/src/tools/rust-analyzer/crates/ide/src/syntax_highlighting/tests.rs
@@ -48,6 +48,7 @@ fn macros() {
     check_highlighting(
         r#"
 //- proc_macros: mirror
+//- /lib.rs crate:lib
 proc_macros::mirror! {
     {
         ,i32 :x pub
@@ -95,11 +96,23 @@ macro without_args {
     }
 }
 
+#[rustc_builtin_macro]
+macro_rules! concat {}
+#[rustc_builtin_macro]
+macro_rules! include {}
+#[rustc_builtin_macro]
+macro_rules! format_args {}
+
+include!(concat!("foo/", "foo.rs"));
+
 fn main() {
-    println!("Hello, {}!", 92);
+    format_args!("Hello, {}!", 92);
     dont_color_me_braces!();
     noop!(noop!(1));
 }
+//- /foo/foo.rs crate:foo
+mod foo {}
+use self::foo as bar;
 "#,
         expect_file!["./test_data/highlight_macros.html"],
         false,
@@ -451,6 +464,8 @@ fn main() {
     let a = '\x65';
     let a = '\x00';
 
+    let a = b'\xFF';
+
     println!("Hello {{Hello}}");
     // from https://doc.rust-lang.org/std/fmt/index.html
     println!("Hello");                 // => "Hello"
@@ -505,9 +520,10 @@ fn main() {
     println!("Hello\nWorld");
     println!("\u{48}\x65\x6C\x6C\x6F World");
 
-    let _ = "\x28\x28\x00\x63\n";
-    let _ = b"\x28\x28\x00\x63\n";
-    let _ = r"\\";
+    let _ = "\x28\x28\x00\x63\xFF\u{FF}\n"; // invalid non-UTF8 escape sequences
+    let _ = b"\x28\x28\x00\x63\xFF\u{FF}\n"; // valid bytes, invalid unicodes
+    let _ = c"\u{FF}\xFF"; // valid bytes, valid unicodes
+    let backslash = r"\\";
 
     println!("{\x41}", A = 92);
     println!("{ничоси}", ничоси = 92);
@@ -520,7 +536,7 @@ fn main() {
     toho!("{}fmt", 0);
     asm!("mov eax, {0}");
     format_args!(concat!("{}"), "{}");
-    format_args!("{}", format_args!("{}", 0));
+    format_args!("{} {} {} {} {} {}", backslash, format_args!("{}", 0), foo, "bar", toho!(), backslash);
 }"#,
         expect_file!["./test_data/highlight_strings.html"],
         false,
@@ -788,6 +804,7 @@ fn test_extern_crate() {
 //- /main.rs crate:main deps:std,alloc
 extern crate std;
 extern crate alloc as abc;
+extern crate unresolved as definitely_unresolved;
 //- /std/lib.rs crate:std
 pub struct S;
 //- /alloc/lib.rs crate:alloc
diff --git a/src/tools/rust-analyzer/crates/ide/src/view_memory_layout.rs b/src/tools/rust-analyzer/crates/ide/src/view_memory_layout.rs
new file mode 100644
index 000000000..2f6332abd
--- /dev/null
+++ b/src/tools/rust-analyzer/crates/ide/src/view_memory_layout.rs
@@ -0,0 +1,409 @@
+use std::fmt;
+
+use hir::{Field, HirDisplay, Layout, Semantics, Type};
+use ide_db::{
+    defs::Definition,
+    helpers::{get_definition, pick_best_token},
+    RootDatabase,
+};
+use syntax::{AstNode, SyntaxKind};
+
+use crate::FilePosition;
+
+pub struct MemoryLayoutNode {
+    pub item_name: String,
+    pub typename: String,
+    pub size: u64,
+    pub alignment: u64,
+    pub offset: u64,
+    pub parent_idx: i64,
+    pub children_start: i64,
+    pub children_len: u64,
+}
+
+pub struct RecursiveMemoryLayout {
+    pub nodes: Vec<MemoryLayoutNode>,
+}
+
+// NOTE: this is currently strictly for testing and so isn't super useful as a visualization tool, however it could be adapted to become one?
+impl fmt::Display for RecursiveMemoryLayout {
+    fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
+        fn process(
+            fmt: &mut fmt::Formatter<'_>,
+            nodes: &Vec<MemoryLayoutNode>,
+            idx: usize,
+            depth: usize,
+        ) -> fmt::Result {
+            let mut out = "\t".repeat(depth);
+            let node = &nodes[idx];
+            out += &format!(
+                "{}: {} (size: {}, align: {}, field offset: {})\n",
+                node.item_name, node.typename, node.size, node.alignment, node.offset
+            );
+            write!(fmt, "{}", out)?;
+            if node.children_start != -1 {
+                for j in nodes[idx].children_start
+                    ..(nodes[idx].children_start + nodes[idx].children_len as i64)
+                {
+                    process(fmt, nodes, j as usize, depth + 1)?;
+                }
+            }
+            Ok(())
+        }
+
+        process(fmt, &self.nodes, 0, 0)
+    }
+}
+
+enum FieldOrTupleIdx {
+    Field(Field),
+    TupleIdx(usize),
+}
+
+impl FieldOrTupleIdx {
+    fn name(&self, db: &RootDatabase) -> String {
+        match *self {
+            FieldOrTupleIdx::Field(f) => f
+                .name(db)
+                .as_str()
+                .map(|s| s.to_owned())
+                .unwrap_or_else(|| format!(".{}", f.name(db).as_tuple_index().unwrap())),
+            FieldOrTupleIdx::TupleIdx(i) => format!(".{i}").to_owned(),
+        }
+    }
+
+    fn index(&self) -> usize {
+        match *self {
+            FieldOrTupleIdx::Field(f) => f.index(),
+            FieldOrTupleIdx::TupleIdx(i) => i,
+        }
+    }
+}
+
+// Feature: View Memory Layout
+//
+// Displays the recursive memory layout of a datatype.
+//
+// |===
+// | Editor  | Action Name
+//
+// | VS Code | **rust-analyzer: View Memory Layout**
+// |===
+pub(crate) fn view_memory_layout(
+    db: &RootDatabase,
+    position: FilePosition,
+) -> Option<RecursiveMemoryLayout> {
+    let sema = Semantics::new(db);
+    let file = sema.parse(position.file_id);
+    let token =
+        pick_best_token(file.syntax().token_at_offset(position.offset), |kind| match kind {
+            SyntaxKind::IDENT => 3,
+            _ => 0,
+        })?;
+
+    let def = get_definition(&sema, token)?;
+
+    let ty = match def {
+        Definition::Adt(it) => it.ty(db),
+        Definition::TypeAlias(it) => it.ty(db),
+        Definition::BuiltinType(it) => it.ty(db),
+        Definition::SelfType(it) => it.self_ty(db),
+        Definition::Local(it) => it.ty(db),
+        Definition::Field(it) => it.ty(db),
+        Definition::Const(it) => it.ty(db),
+        Definition::Static(it) => it.ty(db),
+        _ => return None,
+    };
+
+    fn read_layout(
+        nodes: &mut Vec<MemoryLayoutNode>,
+        db: &RootDatabase,
+        ty: &Type,
+        layout: &Layout,
+        parent_idx: usize,
+    ) {
+        let mut fields = ty
+            .fields(db)
+            .into_iter()
+            .map(|(f, ty)| (FieldOrTupleIdx::Field(f), ty))
+            .chain(
+                ty.tuple_fields(db)
+                    .into_iter()
+                    .enumerate()
+                    .map(|(i, ty)| (FieldOrTupleIdx::TupleIdx(i), ty)),
+            )
+            .collect::<Vec<_>>();
+
+        if fields.len() == 0 {
+            return;
+        }
+
+        fields.sort_by_key(|(f, _)| layout.field_offset(f.index()).unwrap());
+
+        let children_start = nodes.len();
+        nodes[parent_idx].children_start = children_start as i64;
+        nodes[parent_idx].children_len = fields.len() as u64;
+
+        for (field, child_ty) in fields.iter() {
+            if let Ok(child_layout) = child_ty.layout(db) {
+                nodes.push(MemoryLayoutNode {
+                    item_name: field.name(db),
+                    typename: child_ty.display(db).to_string(),
+                    size: child_layout.size(),
+                    alignment: child_layout.align(),
+                    offset: layout.field_offset(field.index()).unwrap_or(0),
+                    parent_idx: parent_idx as i64,
+                    children_start: -1,
+                    children_len: 0,
+                });
+            } else {
+                nodes.push(MemoryLayoutNode {
+                    item_name: field.name(db)
+                        + format!("(no layout data: {:?})", child_ty.layout(db).unwrap_err())
+                            .as_ref(),
+                    typename: child_ty.display(db).to_string(),
+                    size: 0,
+                    offset: 0,
+                    alignment: 0,
+                    parent_idx: parent_idx as i64,
+                    children_start: -1,
+                    children_len: 0,
+                });
+            }
+        }
+
+        for (i, (_, child_ty)) in fields.iter().enumerate() {
+            if let Ok(child_layout) = child_ty.layout(db) {
+                read_layout(nodes, db, &child_ty, &child_layout, children_start + i);
+            }
+        }
+    }
+
+    ty.layout(db)
+        .map(|layout| {
+            let item_name = match def {
+                // def is a datatype
+                Definition::Adt(_)
+                | Definition::TypeAlias(_)
+                | Definition::BuiltinType(_)
+                | Definition::SelfType(_) => "[ROOT]".to_owned(),
+
+                // def is an item
+                def => def
+                    .name(db)
+                    .map(|n| {
+                        n.as_str()
+                            .map(|s| s.to_owned())
+                            .unwrap_or_else(|| format!(".{}", n.as_tuple_index().unwrap()))
+                    })
+                    .unwrap_or("[ROOT]".to_owned()),
+            };
+
+            let typename = ty.display(db).to_string();
+
+            let mut nodes = vec![MemoryLayoutNode {
+                item_name,
+                typename: typename.clone(),
+                size: layout.size(),
+                offset: 0,
+                alignment: layout.align(),
+                parent_idx: -1,
+                children_start: -1,
+                children_len: 0,
+            }];
+            read_layout(&mut nodes, db, &ty, &layout, 0);
+
+            RecursiveMemoryLayout { nodes }
+        })
+        .ok()
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    use crate::fixture;
+    use expect_test::expect;
+
+    fn make_memory_layout(ra_fixture: &str) -> Option<RecursiveMemoryLayout> {
+        let (analysis, position, _) = fixture::annotations(ra_fixture);
+
+        view_memory_layout(&analysis.db, position)
+    }
+
+    #[test]
+    fn view_memory_layout_none() {
+        assert!(make_memory_layout(r#"$0"#).is_none());
+        assert!(make_memory_layout(r#"stru$0ct Blah {}"#).is_none());
+    }
+
+    #[test]
+    fn view_memory_layout_primitive() {
+        expect![[r#"
+            foo: i32 (size: 4, align: 4, field offset: 0)
+        "#]]
+        .assert_eq(
+            &make_memory_layout(
+                r#"
+fn main() {
+    let foo$0 = 109; // default i32
+}
+"#,
+            )
+            .unwrap()
+            .to_string(),
+        );
+    }
+
+    #[test]
+    fn view_memory_layout_constant() {
+        expect![[r#"
+            BLAH: bool (size: 1, align: 1, field offset: 0)
+        "#]]
+        .assert_eq(
+            &make_memory_layout(
+                r#"
+const BLAH$0: bool = 0;
+"#,
+            )
+            .unwrap()
+            .to_string(),
+        );
+    }
+
+    #[test]
+    fn view_memory_layout_static() {
+        expect![[r#"
+            BLAH: bool (size: 1, align: 1, field offset: 0)
+        "#]]
+        .assert_eq(
+            &make_memory_layout(
+                r#"
+static BLAH$0: bool = 0;
+"#,
+            )
+            .unwrap()
+            .to_string(),
+        );
+    }
+
+    #[test]
+    fn view_memory_layout_tuple() {
+        expect![[r#"
+            x: (f64, u8, i64) (size: 24, align: 8, field offset: 0)
+            	.0: f64 (size: 8, align: 8, field offset: 0)
+            	.1: u8 (size: 1, align: 1, field offset: 8)
+            	.2: i64 (size: 8, align: 8, field offset: 16)
+        "#]]
+        .assert_eq(
+            &make_memory_layout(
+                r#"
+fn main() {
+    let x$0 = (101.0, 111u8, 119i64);
+}
+"#,
+            )
+            .unwrap()
+            .to_string(),
+        );
+    }
+
+    #[test]
+    fn view_memory_layout_c_struct() {
+        expect![[r#"
+            [ROOT]: Blah (size: 16, align: 4, field offset: 0)
+            	a: u32 (size: 4, align: 4, field offset: 0)
+            	b: (i32, u8) (size: 8, align: 4, field offset: 4)
+            		.0: i32 (size: 4, align: 4, field offset: 0)
+            		.1: u8 (size: 1, align: 1, field offset: 4)
+            	c: i8 (size: 1, align: 1, field offset: 12)
+        "#]]
+        .assert_eq(
+            &make_memory_layout(
+                r#"
+#[repr(C)]
+struct Blah$0 {
+    a: u32,
+    b: (i32, u8),
+    c: i8,
+}
+"#,
+            )
+            .unwrap()
+            .to_string(),
+        );
+    }
+
+    #[test]
+    fn view_memory_layout_struct() {
+        expect![[r#"
+            [ROOT]: Blah (size: 16, align: 4, field offset: 0)
+            	b: (i32, u8) (size: 8, align: 4, field offset: 0)
+            		.0: i32 (size: 4, align: 4, field offset: 0)
+            		.1: u8 (size: 1, align: 1, field offset: 4)
+            	a: u32 (size: 4, align: 4, field offset: 8)
+            	c: i8 (size: 1, align: 1, field offset: 12)
+        "#]]
+        .assert_eq(
+            &make_memory_layout(
+                r#"
+struct Blah$0 {
+    a: u32,
+    b: (i32, u8),
+    c: i8,
+}
+"#,
+            )
+            .unwrap()
+            .to_string(),
+        );
+    }
+
+    #[test]
+    fn view_memory_layout_member() {
+        expect![[r#"
+            a: bool (size: 1, align: 1, field offset: 0)
+        "#]]
+        .assert_eq(
+            &make_memory_layout(
+                r#"
+#[repr(C)]
+struct Oof {
+    a$0: bool,
+}
+"#,
+            )
+            .unwrap()
+            .to_string(),
+        );
+    }
+
+    #[test]
+    fn view_memory_layout_alias() {
+        let ml_a = make_memory_layout(
+            r#"
+struct X {
+    a: u32,
+    b: i8,
+    c: (f32, f32),
+}
+
+type Foo$0 = X;
+"#,
+        )
+        .unwrap();
+
+        let ml_b = make_memory_layout(
+            r#"
+struct X$0 {
+    a: u32,
+    b: i8,
+    c: (f32, f32),
+}
+"#,
+        )
+        .unwrap();
+
+        assert_eq!(ml_a.to_string(), ml_b.to_string());
+    }
+}