Merge pull request #21792 from bend-n/make-matching-brace-almost-always-proc

make matching brace work when cursor not at bracket

Author: ChayimFriedman2

crates/ide/src/matching_brace.rs

@@ -17,25 +17,37 @@ use syntax::{
 pub(crate) fn matching_brace(file: &SourceFile, offset: TextSize) -> Option<TextSize> {
     const BRACES: &[SyntaxKind] =
         &[T!['{'], T!['}'], T!['['], T![']'], T!['('], T![')'], T![<], T![>], T![|], T![|]];
-    let (brace_token, brace_idx) = file
-        .syntax()
-        .token_at_offset(offset)
+    let current = file.syntax().token_at_offset(offset);
+    if let Some((brace_token, brace_idx)) = current
+        .clone()
         .filter_map(|node| {
             let idx = BRACES.iter().position(|&brace| brace == node.kind())?;
             Some((node, idx))
         })
-        .last()?;
-    let parent = brace_token.parent()?;
-    if brace_token.kind() == T![|] && !ast::ParamList::can_cast(parent.kind()) {
-        cov_mark::hit!(pipes_not_braces);
-        return None;
+        .last()
+    {
+        let parent = brace_token.parent()?;
+        if brace_token.kind() == T![|] && !ast::ParamList::can_cast(parent.kind()) {
+            cov_mark::hit!(pipes_not_braces);
+            return None;
+        }
+        let matching_kind = BRACES[brace_idx ^ 1];
+        let matching_node = parent
+            .children_with_tokens()
+            .filter_map(|it| it.into_token())
+            .find(|node| node.kind() == matching_kind && node != &brace_token)?;
+        Some(matching_node.text_range().start())
+    } else {
+        // when the offset is not at a brace, find first parent
+        current.last()?.parent_ancestors().find_map(|x| {
+            x.children_with_tokens()
+                .filter_map(|it| it.into_token())
+                // with ending brace
+                .filter(|node| BRACES.contains(&node.kind()))
+                .last()
+                .map(|x| x.text_range().start())
+        })
     }
-    let matching_kind = BRACES[brace_idx ^ 1];
-    let matching_node = parent
-        .children_with_tokens()
-        .filter_map(|it| it.into_token())
-        .find(|node| node.kind() == matching_kind && node != &brace_token)?;
-    Some(matching_node.text_range().start())
 }
 
 #[cfg(test)]
@@ -64,6 +76,14 @@ mod tests {
             "fn func(x) { return (2 * (x + 3)$0) + 5;}",
             "fn func(x) { return $0(2 * (x + 3)) + 5;}",
         );
+        do_check(
+            "fn func(x) { return (2 * (x $0+ 3)) + 5;}",
+            "fn func(x) { return (2 * (x + 3$0)) + 5;}",
+        );
+        do_check(
+            "fn func(x) { re$0turn (2 * (x + 3)) + 5;}",
+            "fn func(x) { return (2 * (x + 3)) + 5;$0}",
+        );
 
         {
             cov_mark::check!(pipes_not_braces);