21 files changed, 142 insertions, 14 deletions

diff --git a/crates/ide/src/display/navigation_target.rs b/crates/ide/src/display/navigation_target.rs
index cd8ec54fa..6431e7d6d 100644
--- a/crates/ide/src/display/navigation_target.rs
+++ b/crates/ide/src/display/navigation_target.rs
@@ -5,7 +5,7 @@ use std::fmt;
 use either::Either;
 use hir::{AssocItem, Documentation, FieldSource, HasAttrs, HasSource, InFile, ModuleSource};
 use ide_db::{
-    base_db::{FileId, SourceDatabase},
+    base_db::{FileId, FileRange, SourceDatabase},
     symbol_index::FileSymbolKind,
 };
 use ide_db::{defs::Definition, RootDatabase};
@@ -28,6 +28,7 @@ pub enum SymbolKind {
     ValueParam,
     SelfParam,
     Local,
+    Label,
     Function,
     Const,
     Static,
@@ -223,6 +224,7 @@ impl TryToNav for Definition {
             Definition::Local(it) => Some(it.to_nav(db)),
             Definition::TypeParam(it) => Some(it.to_nav(db)),
             Definition::LifetimeParam(it) => Some(it.to_nav(db)),
+            Definition::Label(it) => Some(it.to_nav(db)),
         }
     }
 }
@@ -421,6 +423,27 @@ impl ToNav for hir::Local {
     }
 }
 
+impl ToNav for hir::Label {
+    fn to_nav(&self, db: &RootDatabase) -> NavigationTarget {
+        let src = self.source(db);
+        let node = src.value.syntax();
+        let FileRange { file_id, range } = src.with_value(node).original_file_range(db);
+        let focus_range =
+            src.value.lifetime().and_then(|lt| lt.lifetime_ident_token()).map(|lt| lt.text_range());
+        let name = self.name(db).to_string().into();
+        NavigationTarget {
+            file_id,
+            name,
+            kind: Some(SymbolKind::Label),
+            full_range: range,
+            focus_range,
+            container_name: None,
+            description: None,
+            docs: None,
+        }
+    }
+}
+
 impl ToNav for hir::TypeParam {
     fn to_nav(&self, db: &RootDatabase) -> NavigationTarget {
         let src = self.source(db);
diff --git a/crates/ide/src/doc_links.rs b/crates/ide/src/doc_links.rs
index b61ea0b3e..e10516f43 100644
--- a/crates/ide/src/doc_links.rs
+++ b/crates/ide/src/doc_links.rs
@@ -193,7 +193,8 @@ fn rewrite_intra_doc_link(
         Definition::SelfType(_)
         | Definition::Local(_)
         | Definition::TypeParam(_)
-        | Definition::LifetimeParam(_) => return None,
+        | Definition::LifetimeParam(_)
+        | Definition::Label(_) => return None,
     }?;
     let krate = resolved.module(db)?.krate();
     let canonical_path = resolved.canonical_path(db)?;
diff --git a/crates/ide/src/goto_definition.rs b/crates/ide/src/goto_definition.rs
index 47dd85ceb..912144f8b 100644
--- a/crates/ide/src/goto_definition.rs
+++ b/crates/ide/src/goto_definition.rs
@@ -1130,4 +1130,19 @@ fn foo<T>() where T: for<'a> Foo<&'a<|> (u8, u16)>, {}
 "#,
         );
     }
+
+    #[test]
+    fn goto_label() {
+        check(
+            r#"
+fn foo<'foo>(_: &'foo ()) {
+    'foo: {
+  //^^^^
+        'bar: loop {
+            break 'foo<|>;
+        }
+    }
+}"#,
+        )
+    }
 }
diff --git a/crates/ide/src/hover.rs b/crates/ide/src/hover.rs
index 52f993cc9..73245fbe7 100644
--- a/crates/ide/src/hover.rs
+++ b/crates/ide/src/hover.rs
@@ -370,7 +370,7 @@ fn hover_for_definition(db: &RootDatabase, def: Definition) -> Option<Markup> {
                 Adt::Enum(it) => from_def_source(db, it, mod_path),
             })
         }
-        Definition::TypeParam(_) | Definition::LifetimeParam(_) => {
+        Definition::TypeParam(_) | Definition::LifetimeParam(_) | Definition::Label(_) => {
             // FIXME: Hover for generic param
             None
         }
diff --git a/crates/ide/src/references.rs b/crates/ide/src/references.rs
index 33b7358f7..21b2d7ca1 100644
--- a/crates/ide/src/references.rs
+++ b/crates/ide/src/references.rs
@@ -130,7 +130,7 @@ pub(crate) fn find_all_refs(
                 kind = ReferenceKind::FieldShorthandForLocal;
             }
         }
-    } else if let Definition::LifetimeParam(_) = def {
+    } else if matches!(def, Definition::LifetimeParam(_) | Definition::Label(_)) {
         kind = ReferenceKind::Lifetime;
     };
 
@@ -1122,4 +1122,26 @@ fn main() {
             "#]],
         );
     }
+
+    #[test]
+    fn test_find_labels() {
+        check(
+            r#"
+fn foo<'a>() -> &'a () {
+    'a: loop {
+        'b: loop {
+            continue 'a<|>;
+        }
+        break 'a;
+    }
+}
+"#,
+            expect![[r#"
+                'a Label FileId(0) 29..32 29..31 Lifetime
+
+                FileId(0) 80..82 Lifetime
+                FileId(0) 108..110 Lifetime
+            "#]],
+        );
+    }
 }
diff --git a/crates/ide/src/references/rename.rs b/crates/ide/src/references/rename.rs
index 15c95f239..854bf194e 100644
--- a/crates/ide/src/references/rename.rs
+++ b/crates/ide/src/references/rename.rs
@@ -1540,4 +1540,29 @@ fn main() {
 }"#,
         );
     }
+
+    #[test]
+    fn test_rename_label() {
+        check(
+            "'foo",
+            r#"
+fn foo<'a>() -> &'a () {
+    'a: {
+        'b: loop {
+            break 'a<|>;
+        }
+    }
+}
+"#,
+            r#"
+fn foo<'a>() -> &'a () {
+    'foo: {
+        'b: loop {
+            break 'foo;
+        }
+    }
+}
+"#,
+        )
+    }
 }
diff --git a/crates/ide/src/syntax_highlighting.rs b/crates/ide/src/syntax_highlighting.rs
index 00c717c7c..5ad96581b 100644
--- a/crates/ide/src/syntax_highlighting.rs
+++ b/crates/ide/src/syntax_highlighting.rs
@@ -560,10 +560,20 @@ fn highlight_element(
         CHAR => HighlightTag::CharLiteral.into(),
         QUESTION => Highlight::new(HighlightTag::Operator) | HighlightModifier::ControlFlow,
         LIFETIME => {
-            let h = Highlight::new(HighlightTag::Symbol(SymbolKind::LifetimeParam));
-            match element.parent().map(|it| it.kind()) {
-                Some(LIFETIME_PARAM) | Some(LABEL) => h | HighlightModifier::Definition,
-                _ => h,
+            let lifetime = element.into_node().and_then(ast::Lifetime::cast).unwrap();
+
+            match NameClass::classify_lifetime(sema, &lifetime) {
+                Some(NameClass::Definition(def)) => {
+                    highlight_def(db, def) | HighlightModifier::Definition
+                }
+                None => match NameRefClass::classify_lifetime(sema, &lifetime) {
+                    Some(NameRefClass::Definition(def)) => highlight_def(db, def),
+                    _ => Highlight::new(HighlightTag::Symbol(SymbolKind::LifetimeParam)),
+                },
+                _ => {
+                    Highlight::new(HighlightTag::Symbol(SymbolKind::LifetimeParam))
+                        | HighlightModifier::Definition
+                }
             }
         }
         p if p.is_punct() => match p {
@@ -825,6 +835,7 @@ fn highlight_def(db: &RootDatabase, def: Definition) -> Highlight {
             return h;
         }
         Definition::LifetimeParam(_) => HighlightTag::Symbol(SymbolKind::LifetimeParam),
+        Definition::Label(_) => HighlightTag::Symbol(SymbolKind::Label),
     }
     .into()
 }
diff --git a/crates/ide/src/syntax_highlighting/html.rs b/crates/ide/src/syntax_highlighting/html.rs
index abcc5cccc..99ba3a59d 100644
--- a/crates/ide/src/syntax_highlighting/html.rs
+++ b/crates/ide/src/syntax_highlighting/html.rs
@@ -64,6 +64,7 @@ body                { margin: 0; }
 pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padding: 0.4em; }
 
 .lifetime           { color: #DFAF8F; font-style: italic; }
+.label              { color: #DFAF8F; font-style: italic; }
 .comment            { color: #7F9F7F; }
 .documentation      { color: #629755; }
 .injected           { opacity: 0.65 ; }
diff --git a/crates/ide/src/syntax_highlighting/tags.rs b/crates/ide/src/syntax_highlighting/tags.rs
index 974f54fa0..2a6cc0cab 100644
--- a/crates/ide/src/syntax_highlighting/tags.rs
+++ b/crates/ide/src/syntax_highlighting/tags.rs
@@ -80,6 +80,7 @@ impl HighlightTag {
                 SymbolKind::LifetimeParam => "lifetime",
                 SymbolKind::Macro => "macro",
                 SymbolKind::Local => "variable",
+                SymbolKind::Label => "label",
                 SymbolKind::ValueParam => "value_param",
                 SymbolKind::SelfParam => "self_keyword",
                 SymbolKind::Impl => "self_type",
diff --git a/crates/ide/src/syntax_highlighting/test_data/highlight_assoc_functions.html b/crates/ide/src/syntax_highlighting/test_data/highlight_assoc_functions.html
index db6f32d33..506ebe60e 100644
--- a/crates/ide/src/syntax_highlighting/test_data/highlight_assoc_functions.html
+++ b/crates/ide/src/syntax_highlighting/test_data/highlight_assoc_functions.html
@@ -4,6 +4,7 @@ body                { margin: 0; }
 pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padding: 0.4em; }
 
 .lifetime           { color: #DFAF8F; font-style: italic; }
+.label              { color: #DFAF8F; font-style: italic; }
 .comment            { color: #7F9F7F; }
 .documentation      { color: #629755; }
 .injected           { opacity: 0.65 ; }
diff --git a/crates/ide/src/syntax_highlighting/test_data/highlight_doctest.html b/crates/ide/src/syntax_highlighting/test_data/highlight_doctest.html
index 4e511baa9..4dd7413ba 100644
--- a/crates/ide/src/syntax_highlighting/test_data/highlight_doctest.html
+++ b/crates/ide/src/syntax_highlighting/test_data/highlight_doctest.html
@@ -4,6 +4,7 @@ body                { margin: 0; }
 pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padding: 0.4em; }
 
 .lifetime           { color: #DFAF8F; font-style: italic; }
+.label              { color: #DFAF8F; font-style: italic; }
 .comment            { color: #7F9F7F; }
 .documentation      { color: #629755; }
 .injected           { opacity: 0.65 ; }
diff --git a/crates/ide/src/syntax_highlighting/test_data/highlight_extern_crate.html b/crates/ide/src/syntax_highlighting/test_data/highlight_extern_crate.html
index 800d894c7..ed452586a 100644
--- a/crates/ide/src/syntax_highlighting/test_data/highlight_extern_crate.html
+++ b/crates/ide/src/syntax_highlighting/test_data/highlight_extern_crate.html
@@ -4,6 +4,7 @@ body                { margin: 0; }
 pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padding: 0.4em; }
 
 .lifetime           { color: #DFAF8F; font-style: italic; }
+.label              { color: #DFAF8F; font-style: italic; }
 .comment            { color: #7F9F7F; }
 .documentation      { color: #629755; }
 .injected           { opacity: 0.65 ; }
diff --git a/crates/ide/src/syntax_highlighting/test_data/highlight_injection.html b/crates/ide/src/syntax_highlighting/test_data/highlight_injection.html
index 7f18ad297..92e7dc3e4 100644
--- a/crates/ide/src/syntax_highlighting/test_data/highlight_injection.html
+++ b/crates/ide/src/syntax_highlighting/test_data/highlight_injection.html
@@ -4,6 +4,7 @@ body                { margin: 0; }
 pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padding: 0.4em; }
 
 .lifetime           { color: #DFAF8F; font-style: italic; }
+.label              { color: #DFAF8F; font-style: italic; }
 .comment            { color: #7F9F7F; }
 .documentation      { color: #629755; }
 .injected           { opacity: 0.65 ; }
diff --git a/crates/ide/src/syntax_highlighting/test_data/highlight_strings.html b/crates/ide/src/syntax_highlighting/test_data/highlight_strings.html
index c843b5085..31dad5d42 100644
--- a/crates/ide/src/syntax_highlighting/test_data/highlight_strings.html
+++ b/crates/ide/src/syntax_highlighting/test_data/highlight_strings.html
@@ -4,6 +4,7 @@ body                { margin: 0; }
 pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padding: 0.4em; }
 
 .lifetime           { color: #DFAF8F; font-style: italic; }
+.label              { color: #DFAF8F; font-style: italic; }
 .comment            { color: #7F9F7F; }
 .documentation      { color: #629755; }
 .injected           { opacity: 0.65 ; }
diff --git a/crates/ide/src/syntax_highlighting/test_data/highlight_unsafe.html b/crates/ide/src/syntax_highlighting/test_data/highlight_unsafe.html
index d26f48516..e3a0aa317 100644
--- a/crates/ide/src/syntax_highlighting/test_data/highlight_unsafe.html
+++ b/crates/ide/src/syntax_highlighting/test_data/highlight_unsafe.html
@@ -4,6 +4,7 @@ body                { margin: 0; }
 pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padding: 0.4em; }
 
 .lifetime           { color: #DFAF8F; font-style: italic; }
+.label              { color: #DFAF8F; font-style: italic; }
 .comment            { color: #7F9F7F; }
 .documentation      { color: #629755; }
 .injected           { opacity: 0.65 ; }
diff --git a/crates/ide/src/syntax_highlighting/test_data/highlighting.html b/crates/ide/src/syntax_highlighting/test_data/highlighting.html
index 588e86a34..72ff9dd40 100644
--- a/crates/ide/src/syntax_highlighting/test_data/highlighting.html
+++ b/crates/ide/src/syntax_highlighting/test_data/highlighting.html
@@ -4,6 +4,7 @@ body                { margin: 0; }
 pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padding: 0.4em; }
 
 .lifetime           { color: #DFAF8F; font-style: italic; }
+.label              { color: #DFAF8F; font-style: italic; }
 .comment            { color: #7F9F7F; }
 .documentation      { color: #629755; }
 .injected           { opacity: 0.65 ; }
@@ -194,6 +195,11 @@ pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padd
     <span class="keyword">let</span> <span class="variable declaration">baz</span> <span class="operator">=</span> <span class="operator">-</span><span class="variable">baz</span><span class="punctuation">;</span>
 
     <span class="keyword">let</span> <span class="punctuation">_</span> <span class="operator">=</span> <span class="operator">!</span><span class="bool_literal">true</span><span class="punctuation">;</span>
+
+    <span class="label declaration">'foo</span><span class="punctuation">:</span> <span class="keyword control">loop</span> <span class="punctuation">{</span>
+        <span class="keyword control">break</span> <span class="label">'foo</span><span class="punctuation">;</span>
+        <span class="keyword control">continue</span> <span class="label">'foo</span><span class="punctuation">;</span>
+    <span class="punctuation">}</span>
 <span class="punctuation">}</span>
 
 <span class="keyword">enum</span> <span class="enum declaration">Option</span><span class="punctuation">&lt;</span><span class="type_param declaration">T</span><span class="punctuation">&gt;</span> <span class="punctuation">{</span>
diff --git a/crates/ide/src/syntax_highlighting/test_data/rainbow_highlighting.html b/crates/ide/src/syntax_highlighting/test_data/rainbow_highlighting.html
index c7589605f..8b3dfa69f 100644
--- a/crates/ide/src/syntax_highlighting/test_data/rainbow_highlighting.html
+++ b/crates/ide/src/syntax_highlighting/test_data/rainbow_highlighting.html
@@ -4,6 +4,7 @@ body                { margin: 0; }
 pre                 { color: #DCDCCC; background: #3F3F3F; font-size: 22px; padding: 0.4em; }
 
 .lifetime           { color: #DFAF8F; font-style: italic; }
+.label              { color: #DFAF8F; font-style: italic; }
 .comment            { color: #7F9F7F; }
 .documentation      { color: #629755; }
 .injected           { opacity: 0.65 ; }
diff --git a/crates/ide/src/syntax_highlighting/tests.rs b/crates/ide/src/syntax_highlighting/tests.rs
index f53d2c3ba..e0df0d2b5 100644
--- a/crates/ide/src/syntax_highlighting/tests.rs
+++ b/crates/ide/src/syntax_highlighting/tests.rs
@@ -168,6 +168,11 @@ fn main() {
     let baz = -baz;
 
     let _ = !true;
+
+    'foo: loop {
+        break 'foo;
+        continue 'foo;
+    }
 }
 
 enum Option<T> {
diff --git a/crates/ide_db/src/defs.rs b/crates/ide_db/src/defs.rs
index 9d7dce1d4..d33a6cb86 100644
--- a/crates/ide_db/src/defs.rs
+++ b/crates/ide_db/src/defs.rs
@@ -6,8 +6,8 @@
 // FIXME: this badly needs rename/rewrite (matklad, 2020-02-06).
 
 use hir::{
-    db::HirDatabase, Crate, Field, HasVisibility, Impl, LifetimeParam, Local, MacroDef, Module,
-    ModuleDef, Name, PathResolution, Semantics, TypeParam, Visibility,
+    db::HirDatabase, Crate, Field, HasVisibility, Impl, Label, LifetimeParam, Local, MacroDef,
+    Module, ModuleDef, Name, PathResolution, Semantics, TypeParam, Visibility,
 };
 use syntax::{
     ast::{self, AstNode},
@@ -26,7 +26,7 @@ pub enum Definition {
     Local(Local),
     TypeParam(TypeParam),
     LifetimeParam(LifetimeParam),
-    // FIXME: Label
+    Label(Label),
 }
 
 impl Definition {
@@ -39,6 +39,7 @@ impl Definition {
             Definition::Local(it) => Some(it.module(db)),
             Definition::TypeParam(it) => Some(it.module(db)),
             Definition::LifetimeParam(it) => Some(it.module(db)),
+            Definition::Label(it) => Some(it.module(db)),
         }
     }
 
@@ -51,6 +52,7 @@ impl Definition {
             Definition::Local(_) => None,
             Definition::TypeParam(_) => None,
             Definition::LifetimeParam(_) => None,
+            Definition::Label(_) => None,
         }
     }
 
@@ -77,6 +79,7 @@ impl Definition {
             Definition::Local(it) => it.name(db)?,
             Definition::TypeParam(it) => it.name(db),
             Definition::LifetimeParam(it) => it.name(db),
+            Definition::Label(it) => it.name(db),
         };
         Some(name)
     }
@@ -248,7 +251,10 @@ impl NameClass {
                     let def = sema.to_def(&it)?;
                     Some(NameClass::Definition(Definition::LifetimeParam(def)))
                 },
-                ast::Label(_it) => None,
+                ast::Label(it) => {
+                    let def = sema.to_def(&it)?;
+                    Some(NameClass::Definition(Definition::Label(def)))
+                },
                 _ => None,
             }
         }
@@ -370,6 +376,9 @@ impl NameRefClass {
         let _p = profile::span("classify_lifetime_ref").detail(|| lifetime.to_string());
         let parent = lifetime.syntax().parent()?;
         match parent.kind() {
+            SyntaxKind::BREAK_EXPR | SyntaxKind::CONTINUE_EXPR => {
+                sema.resolve_label(lifetime).map(Definition::Label).map(NameRefClass::Definition)
+            }
             SyntaxKind::LIFETIME_ARG
             | SyntaxKind::SELF_PARAM
             | SyntaxKind::TYPE_BOUND
@@ -387,7 +396,6 @@ impl NameRefClass {
                     .map(Definition::LifetimeParam)
                     .map(NameRefClass::Definition)
             }
-            SyntaxKind::BREAK_EXPR | SyntaxKind::CONTINUE_EXPR => None,
             _ => None,
         }
     }
diff --git a/crates/rust-analyzer/src/semantic_tokens.rs b/crates/rust-analyzer/src/semantic_tokens.rs
index 1daad1c98..c2f6a655d 100644
--- a/crates/rust-analyzer/src/semantic_tokens.rs
+++ b/crates/rust-analyzer/src/semantic_tokens.rs
@@ -45,6 +45,7 @@ define_semantic_token_types![
     (FORMAT_SPECIFIER, "formatSpecifier"),
     (GENERIC, "generic"),
     (LIFETIME, "lifetime"),
+    (LABEL, "label"),
     (PUNCTUATION, "punctuation"),
     (SELF_KEYWORD, "selfKeyword"),
     (TYPE_ALIAS, "typeAlias"),
diff --git a/crates/rust-analyzer/src/to_proto.rs b/crates/rust-analyzer/src/to_proto.rs
index 5a1ae96aa..753aad628 100644
--- a/crates/rust-analyzer/src/to_proto.rs
+++ b/crates/rust-analyzer/src/to_proto.rs
@@ -46,7 +46,8 @@ pub(crate) fn symbol_kind(symbol_kind: SymbolKind) -> lsp_types::SymbolKind {
         SymbolKind::Local
         | SymbolKind::SelfParam
         | SymbolKind::LifetimeParam
-        | SymbolKind::ValueParam => lsp_types::SymbolKind::Variable,
+        | SymbolKind::ValueParam
+        | SymbolKind::Label => lsp_types::SymbolKind::Variable,
         SymbolKind::Union => lsp_types::SymbolKind::Struct,
     }
 }
@@ -378,6 +379,7 @@ fn semantic_token_type_and_modifiers(
             SymbolKind::Field => lsp_types::SemanticTokenType::PROPERTY,
             SymbolKind::TypeParam => lsp_types::SemanticTokenType::TYPE_PARAMETER,
             SymbolKind::LifetimeParam => semantic_tokens::LIFETIME,
+            SymbolKind::Label => semantic_tokens::LABEL,
             SymbolKind::ValueParam => lsp_types::SemanticTokenType::PARAMETER,
             SymbolKind::SelfParam => semantic_tokens::SELF_KEYWORD,
             SymbolKind::Local => lsp_types::SemanticTokenType::VARIABLE,