perf: improve determine_export_assignments (2)

* eliminate Atom clone
* rewrite collect hidden_exports

crates/rspack_plugin_javascript/src/dependency/esm/harmony_export_imported_specifier_dependency.rs

@@ -1,4 +1,3 @@
-use std::cell::OnceCell;
 use std::{collections::HashMap, sync::Arc};
 
 use rspack_core::{
@@ -308,14 +307,11 @@ impl HarmonyExportImportedSpecifierDependency {
     let hidden_exports = self
       .discover_active_exports_from_other_star_exports(module_graph)
       .map(|other_star_exports| {
-        let mut hide_exports = HashSet::default();
-        for i in 0..other_star_exports.names_slice {
-          hide_exports.insert(other_star_exports.names[i].clone());
-        }
-        for e in ignored_exports.iter() {
-          hide_exports.remove(e);
-        }
-        hide_exports
+        other_star_exports.names.into_iter()
+            .take(other_star_exports.names_slice)
+            .filter(|name| !ignored_exports.contains(name))
+            .cloned()
+            .collect::<HashSet<_>>()
       });
     if !no_extra_exports && !no_extra_imports {
       return StarReexportsInfo {
@@ -418,10 +414,10 @@ impl HarmonyExportImportedSpecifierDependency {
     }
   }
 
-  pub fn discover_active_exports_from_other_star_exports(
+  pub fn discover_active_exports_from_other_star_exports<'a>(
     &self,
-    module_graph: &ModuleGraph,
-  ) -> Option<DiscoverActiveExportsFromOtherStarExportsRet> {
+    module_graph: &'a ModuleGraph,
+  ) -> Option<DiscoverActiveExportsFromOtherStarExportsRet<'a>> {
     if let Some(other_star_exports) = &self.other_star_exports {
       if other_star_exports.is_empty() {
         return None;
@@ -828,8 +824,8 @@ impl HarmonyExportImportedSpecifierDependency {
 }
 
 #[derive(Debug)]
-pub struct DiscoverActiveExportsFromOtherStarExportsRet {
-  names: Vec<Atom>,
+pub struct DiscoverActiveExportsFromOtherStarExportsRet<'a> {
+  names: Vec<&'a Atom>,
   names_slice: usize,
   pub dependency_indices: Vec<usize>,
   pub dependency_index: usize,
@@ -1349,34 +1345,31 @@ pub struct StarReexportsInfo {
 }
 
 /// return (names, dependency_indices)
-fn determine_export_assignments(
-  module_graph: &ModuleGraph,
+fn determine_export_assignments<'a>(
+  module_graph: &'a ModuleGraph,
   dependencies: &[DependencyId],
   additional_dependency: Option<DependencyId>,
-) -> (Vec<Atom>, Vec<usize>) {
+) -> (Vec<&'a Atom>, Vec<usize>) {
   // https://github.com/webpack/webpack/blob/ac7e531436b0d47cd88451f497cdfd0dad41535d/lib/dependencies/HarmonyExportImportedSpecifierDependency.js#L109
-  // js `Set` keep the insertion order, use `IndexSet` to align there behavior
+  // js `Set` keep the insertion order
   let mut names = Vec::new();
   let mut hints = HashSet::default();
   let mut dependency_indices =
       Vec::with_capacity(dependencies.len() + additional_dependency.is_some() as usize);
-  let empty = OnceCell::new();
 
   for dependency in dependencies.iter().chain(additional_dependency.iter()) {
     if let Some(module_identifier) = module_graph.module_identifier_by_dependency_id(dependency) {
       let exports_info = module_graph.get_exports_info(module_identifier);
       for export_info_id in exports_info.exports.values() {
         let export_info = module_graph.get_export_info_by_id(export_info_id);
         // SAFETY: This is safe because a real export can't export empty string
-        let export_info_name = export_info.name
-            .as_ref()
-            .unwrap_or_else(|| empty.get_or_init(Atom::default));
+        let export_info_name = export_info.name.as_ref().expect("export name is empty");
         if matches!(export_info.provided, Some(ExportInfoProvided::True))
           && export_info_name != "default"
           && !hints.contains(export_info_name)
         {
+          names.push(export_info_name);
           hints.insert(export_info_name);
-          names.push(export_info_name.clone());
         }
       }
     }