feat: find references on control-flow kws

src/tools/rust-analyzer/crates/ide/src/references.rs

@@ -24,7 +24,7 @@ use syntax::{
     SyntaxNode, TextRange, TextSize, T,
 };
 
-use crate::{FilePosition, NavigationTarget, TryToNav};
+use crate::{highlight_related, FilePosition, HighlightedRange, NavigationTarget, TryToNav};
 
 #[derive(Debug, Clone)]
 pub struct ReferenceSearchResult {
@@ -103,6 +103,11 @@ pub(crate) fn find_all_refs(
         }
     };
 
+    // Find references for control-flow keywords.
+    if let Some(res) = handle_control_flow_keywords(sema, position) {
+        return Some(vec![res]);
+    }
+
     match name_for_constructor_search(&syntax, position) {
         Some(name) => {
             let def = match NameClass::classify(sema, &name)? {
@@ -296,6 +301,34 @@ fn is_lit_name_ref(name_ref: &ast::NameRef) -> bool {
     }).unwrap_or(false)
 }
 
+fn handle_control_flow_keywords(
+    sema: &Semantics<'_, RootDatabase>,
+    FilePosition { file_id, offset }: FilePosition,
+) -> Option<ReferenceSearchResult> {
+    let file = sema.parse(file_id);
+    let token = file.syntax().token_at_offset(offset).find(|t| t.kind().is_keyword())?;
+
+    let refs = match token.kind() {
+        T![fn] | T![return] | T![try] => highlight_related::highlight_exit_points(sema, token)?,
+        T![async] => highlight_related::highlight_yield_points(sema, token)?,
+        T![loop] | T![while] | T![break] | T![continue] => {
+            highlight_related::highlight_break_points(sema, token)?
+        }
+        T![for] if token.parent().and_then(ast::ForExpr::cast).is_some() => {
+            highlight_related::highlight_break_points(sema, token)?
+        }
+        _ => return None,
+    }
+    .into_iter()
+    .map(|HighlightedRange { range, category }| (range, category))
+    .collect();
+
+    Some(ReferenceSearchResult {
+        declaration: None,
+        references: IntMap::from_iter([(file_id, refs)]),
+    })
+}
+
 #[cfg(test)]
 mod tests {
     use expect_test::{expect, Expect};
@@ -2187,4 +2220,223 @@ fn test() {
             "#]],
         );
     }
+
+    #[test]
+    fn goto_ref_fn_kw() {
+        check(
+            r#"
+macro_rules! N {
+    ($i:ident, $x:expr, $blk:expr) => {
+        for $i in 0..$x {
+            $blk
+        }
+    };
+}
+
+fn main() {
+    $0fn f() {
+        N!(i, 5, {
+            println!("{}", i);
+            return;
+        });
+
+        for i in 1..5 {
+            return;
+        }
+
+       (|| {
+            return;
+        })();
+    }
+}
+"#,
+            expect![[r#"
+                FileId(0) 136..138
+                FileId(0) 207..213
+                FileId(0) 264..270
+            "#]],
+        )
+    }
+
+    #[test]
+    fn goto_ref_exit_points() {
+        check(
+            r#"
+fn$0 foo() -> u32 {
+    if true {
+        return 0;
+    }
+
+    0?;
+    0xDEAD_BEEF
+}
+"#,
+            expect![[r#"
+                FileId(0) 0..2
+                FileId(0) 62..63
+                FileId(0) 40..46
+                FileId(0) 69..80
+            "#]],
+        );
+    }
+
+    #[test]
+    fn test_ref_yield_points() {
+        check(
+            r#"
+pub async$0 fn foo() {
+    let x = foo()
+        .await
+        .await;
+    || { 0.await };
+    (async { 0.await }).await
+}
+"#,
+            expect![[r#"
+                FileId(0) 4..9
+                FileId(0) 63..68
+                FileId(0) 48..53
+                FileId(0) 114..119
+            "#]],
+        );
+    }
+
+    #[test]
+    fn goto_ref_for_kw() {
+        check(
+            r#"
+fn main() {
+    $0for i in 1..5 {
+        break;
+        continue;
+    }
+}
+"#,
+            expect![[r#"
+                FileId(0) 16..19
+                FileId(0) 40..45
+                FileId(0) 55..63
+            "#]],
+        )
+    }
+
+    #[test]
+    fn goto_ref_on_break_kw() {
+        check(
+            r#"
+fn main() {
+    for i in 1..5 {
+        $0break;
+        continue;
+    }
+}
+"#,
+            expect![[r#"
+                FileId(0) 16..19
+                FileId(0) 40..45
+            "#]],
+        )
+    }
+
+    #[test]
+    fn goto_ref_on_break_kw_for_block() {
+        check(
+            r#"
+fn main() {
+    'a:{
+        $0break 'a;
+    }
+}
+"#,
+            expect![[r#"
+                FileId(0) 16..19
+                FileId(0) 29..37
+            "#]],
+        )
+    }
+
+    #[test]
+    fn goto_ref_on_break_with_label() {
+        check(
+            r#"
+fn foo() {
+    'outer: loop {
+         break;
+         'inner: loop {
+            'innermost: loop {
+            }
+            $0break 'outer;
+            break;
+        }
+        break;
+    }
+}
+"#,
+            expect![[r#"
+                FileId(0) 15..27
+                FileId(0) 39..44
+                FileId(0) 127..139
+                FileId(0) 178..183
+            "#]],
+        );
+    }
+
+    #[test]
+    fn goto_ref_on_return_in_try() {
+        check(
+            r#"
+fn main() {
+    fn f() {
+        try {
+            $0return;
+        }
+
+        return;
+    }
+    return;
+}
+"#,
+            expect![[r#"
+                FileId(0) 16..18
+                FileId(0) 51..57
+                FileId(0) 78..84
+            "#]],
+        )
+    }
+
+    #[test]
+    fn goto_ref_on_break_in_try() {
+        check(
+            r#"
+fn main() {
+    for i in 1..100 {
+        let x: Result<(), ()> = try {
+            $0break;
+        };
+    }
+}
+"#,
+            expect![[r#"
+                FileId(0) 16..19
+                FileId(0) 84..89
+            "#]],
+        )
+    }
+
+    #[test]
+    fn goto_ref_on_return_in_async_block() {
+        check(
+            r#"
+fn main() {
+    $0async {
+        return;
+    }
+}
+"#,
+            expect![[r#"
+                FileId(0) 16..21
+                FileId(0) 32..38
+            "#]],
+        )
+    }
 }