fix: don't rename symbols that show many times. Fixes #419

rolldown · Jan 30, 2024 · f985755 · f985755
1 parent a755899
commit f985755
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Showing 3 changed files with 21 additions and 15 deletions.
diff --git a/crates/rolldown/src/bundler/utils/renamer.rs b/crates/rolldown/src/bundler/utils/renamer.rs
@@ -72,17 +72,23 @@ impl<'name> Renamer<'name> {
 
         let mut count = 1;
         let mut candidate_name = Cow::Borrowed(binding_name);
-        loop {
-          let is_shadowed =
-            stack.iter().any(|used_canonical_names| used_canonical_names.contains(&candidate_name));
-
-          if is_shadowed {
-            candidate_name = Cow::Owned(format!("{binding_name}${count}").into());
-            count += 1;
-          } else {
-            used_canonical_names_for_this_scope.insert(candidate_name.clone());
-            canonical_names.insert(binding_ref, candidate_name.into_owned());
-            break;
+        match canonical_names.entry(binding_ref) {
+          std::collections::hash_map::Entry::Vacant(slot) => loop {
+            let is_shadowed = stack
+              .iter()
+              .any(|used_canonical_names| used_canonical_names.contains(&candidate_name));
+
+            if is_shadowed {
+              candidate_name = Cow::Owned(format!("{binding_name}${count}").into());
+              count += 1;
+            } else {
+              used_canonical_names_for_this_scope.insert(candidate_name.clone());
+              slot.insert(candidate_name.into_owned());
+              break;
+            }
+          },
+          std::collections::hash_map::Entry::Occupied(_) => {
+            // The symbol is already renamed
           }
         }
       });

diff --git a/crates/rolldown/tests/esbuild/default/nested_scope_bug/artifacts.snap b/crates/rolldown/tests/esbuild/default/nested_scope_bug/artifacts.snap
@@ -11,10 +11,10 @@ input_file: crates/rolldown/tests/esbuild/default/nested_scope_bug
 // entry.js
 (() => {
 	function a() {
-		b$1();
+		b();
 	}
 	{
-		var b$1 = () => {
+		var b = () => {
 		};
 	}
 	a();

diff --git a/crates/rolldown/tests/esbuild/default/var_relocating_bundle/artifacts.snap b/crates/rolldown/tests/esbuild/default/var_relocating_bundle/artifacts.snap
@@ -11,8 +11,8 @@ input_file: crates/rolldown/tests/esbuild/default/var_relocating_bundle
 // function-nested.js
 function x() {
 	if (true) {
-		var a$1;
-		for (var b$1; 0; )		;		for (var e$1 of  []) 		;		for (var {f:f$1, x:[g$1]} of  []) 		;		for (var h$1 in {}) 		;		for (var {j:j$1, x:[k$1]} in {}) 		;		function l() {
+		var a;
+		for (var b; 0; )		;		for (var e of  []) 		;		for (var {f:f, x:[g]} of  []) 		;		for (var h in {}) 		;		for (var {j:j, x:[k]} in {}) 		;		function l() {
 		}
 	}
 }