chore: reduce component overhead (#3)

Reviewed-on: reya/gpui-native-kit#3

crates/editor/src/highlight.rs

@@ -67,17 +67,8 @@ pub struct HighlightedCode {
 
 /// Highlights `source` with `language`'s tree-sitter grammar.
 pub fn highlight(source: &str, language: Language) -> HighlightedCode {
-    highlight_with_tree(source, language, None).0
-}
-
-/// Highlights `source`, reusing `old_tree` so only the changed region is re-lexed.
-pub fn highlight_with_tree(
-    source: &str,
-    language: Language,
-    old_tree: Option<&tree_sitter::Tree>,
-) -> (HighlightedCode, Option<tree_sitter::Tree>) {
     let Some((grammar, query_source)) = grammar_for(language) else {
-        return (plain(source), None);
+        return plain(source);
     };
 
     HIGHLIGHTERS.with(|cache| {
@@ -104,11 +95,11 @@ pub fn highlight_with_tree(
             .as_mut();
 
         let Some(highlighter) = highlighter else {
-            return (plain(source), None);
+            return plain(source);
         };
 
-        let Some(tree) = highlighter.parser.parse(source, old_tree) else {
-            return (plain(source), None);
+        let Some(tree) = highlighter.parser.parse(source, None) else {
+            return plain(source);
         };
 
         // One role per byte; matches arrive in query order
@@ -134,7 +125,7 @@ pub fn highlight_with_tree(
             }
         }
 
-        (build_lines(source, &role_at), Some(tree))
+        build_lines(source, &role_at)
     })
 }