fix: invalid output for conflict global and local name (#359)

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### Description

Fixes #357.

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### Test Plan

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---

crates/rolldown/src/bundler/chunk/de_conflict.rs

@@ -21,7 +21,7 @@ impl Chunk {
       .flatten()
       .for_each(|name| {
         // global names should be reserved
-        renamer.inc(name);
+        renamer.reserve(name);
       });
 
     self.imports_from_other_chunks.iter().flat_map(|(_, items)| items.iter()).for_each(|item| {

crates/rolldown/src/bundler/chunk/render_chunk_imports.rs

@@ -25,7 +25,8 @@ impl Chunk {
       let mut import_items = named_imports
         .iter()
         .filter_map(|item| {
-          let alias = graph.symbols.get_original_name(item.imported_as);
+          let canonical_ref = graph.symbols.par_canonical_ref_for(item.imported_as);
+          let alias = &self.canonical_names[&canonical_ref];
           match &item.imported {
             Specifier::Star => {
               is_importee_imported = true;
@@ -63,18 +64,15 @@ impl Chunk {
       let mut import_items = items
         .iter()
         .map(|item| {
-          let imported = importee_chunk
-            .canonical_names
-            .get(&graph.symbols.par_canonical_ref_for(item.import_ref))
-            .cloned()
-            .unwrap();
-          let Specifier::Literal(alias) = item.export_alias.as_ref().unwrap() else {
+          let canonical_ref = graph.symbols.par_canonical_ref_for(item.import_ref);
+          let local_binding = &self.canonical_names[&canonical_ref];
+          let Specifier::Literal(export_alias) = item.export_alias.as_ref().unwrap() else {
             panic!("should not be star import from other chunks")
           };
-          if imported == alias {
-            format!("{imported}")
+          if export_alias == local_binding {
+            format!("{export_alias}")
           } else {
-            format!("{imported} as {alias}")
+            format!("{export_alias} as {local_binding}")
           }
         })
         .collect::<Vec<_>>();

crates/rolldown/src/bundler/utils/renamer.rs

@@ -9,7 +9,8 @@ use super::symbols::Symbols;
 
 #[derive(Debug)]
 pub struct Renamer<'name> {
-  top_level_name_to_count: FxHashMap<Cow<'name, Atom>, u32>,
+  /// The usage count of top level names
+  top_level_name_counts: FxHashMap<Cow<'name, Atom>, u32>,
   used_canonical_names: FxHashSet<Cow<'name, Atom>>,
   module_to_used_canonical_name_count: IndexVec<ModuleId, FxHashMap<Cow<'name, Atom>, u32>>,
   canonical_names: FxHashMap<SymbolRef, Atom>,
@@ -19,28 +20,27 @@ pub struct Renamer<'name> {
 impl<'name> Renamer<'name> {
   pub fn new(symbols: &'name Symbols, modules_len: usize) -> Self {
     Self {
-      top_level_name_to_count: FxHashMap::default(),
+      top_level_name_counts: FxHashMap::default(),
       canonical_names: FxHashMap::default(),
       symbols,
       used_canonical_names: FxHashSet::default(),
       module_to_used_canonical_name_count: index_vec::index_vec![FxHashMap::default(); modules_len],
     }
   }
 
-  pub fn inc(&mut self, name: Cow<'name, Atom>) {
-    *self.top_level_name_to_count.entry(name).or_default() += 1;
+  pub fn reserve(&mut self, name: Cow<'name, Atom>) {
+    let count = self.top_level_name_counts.entry(name).or_default();
+    debug_assert!(*count <= 1, "It's unnecessary to reserve a global name twice");
+    *count = 1;
   }
 
   pub fn add_top_level_symbol(&mut self, symbol_ref: SymbolRef) {
     let canonical_ref = self.symbols.par_canonical_ref_for(symbol_ref);
     let original_name = Cow::Borrowed(self.symbols.get_original_name(canonical_ref));
 
     match self.canonical_names.entry(canonical_ref) {
-      std::collections::hash_map::Entry::Occupied(_) => {
-        // The symbol is already renamed
-      }
       std::collections::hash_map::Entry::Vacant(vacant) => {
-        let count = self.top_level_name_to_count.entry(original_name.clone()).or_default();
+        let count = self.top_level_name_counts.entry(original_name.clone()).or_default();
         let canonical_name = if *count == 0 {
           original_name
         } else {
@@ -50,6 +50,9 @@ impl<'name> Renamer<'name> {
         vacant.insert(canonical_name.into_owned());
         *count += 1;
       }
+      std::collections::hash_map::Entry::Occupied(_) => {
+        // The symbol is already renamed
+      }
     }
   }
 

crates/rolldown/tests/fixtures/deconflict/conflict_between_global_and_local_binding/artifacts.snap

@@ -0,0 +1,26 @@
+---
+source: crates/rolldown/tests/common/case.rs
+expression: content
+input_file: crates/rolldown/tests/fixtures/deconflict/conflict_between_global_and_local_binding
+---
+# Assets
+
+## main.mjs
+
+```js
+import { default as assert } from "node:assert";
+import { __commonJS as __commonJS$1 } from "./_rolldown_runtime.mjs";
+
+// main.js
+var require_main = __commonJS$1({
+	'main.js'(exports, module) {
+
+		module.exports = 'main';
+		globalThis.__commonJS = 0
+		__commonJS = 1
+		assert.equal(__commonJS, 1)
+
+	}
+});
+export default require_main();
+```

crates/rolldown/tests/fixtures/deconflict/conflict_between_global_and_local_binding/main.js

@@ -0,0 +1,5 @@
+import assert from 'node:assert'
+module.exports = 'main';
+globalThis.__commonJS = 0
+__commonJS = 1
+assert.equal(__commonJS, 1)

crates/rolldown/tests/fixtures/deconflict/conflict_between_global_and_local_binding/test.config.json

@@ -0,0 +1,7 @@
+{
+  "input": {
+    "external": [
+      "node:assert"
+    ]
+  }
+}