fix(es/renamer): Fix (broken) identifier preserving API (#10474)

**Description:**

The previous API is just broken

Author: kdy1

crates/swc_ecma_minifier/src/pass/mangle_names/mod.rs

@@ -48,36 +48,29 @@ pub(crate) fn mangle_names(
             keep_class_names: options.keep_class_names,
             top_level_mark,
             ignore_eval: options.eval,
-            preserved_symbols: options.reserved.iter().cloned().collect(),
         },
         ManglingRenamer {
             chars,
-            preserved,
+            preserved: &preserved,
             cache,
             mangle_name_cache,
+            reserved: &options.reserved,
         },
     ));
 }
 
-struct ManglingRenamer {
+struct ManglingRenamer<'a> {
     chars: Base54Chars,
-    preserved: FxHashSet<Id>,
+    preserved: &'a FxHashSet<Id>,
     cache: Option<RenameMap>,
     mangle_name_cache: Option<Arc<dyn MangleCache>>,
+    reserved: &'a Vec<Atom>,
 }
 
-impl Renamer for ManglingRenamer {
+impl<'a> Renamer for ManglingRenamer<'a> {
     const MANGLE: bool = true;
     const RESET_N: bool = false;
 
-    fn preserved_ids_for_module(&mut self, _: &Module) -> FxHashSet<Id> {
-        self.preserved.clone()
-    }
-
-    fn preserved_ids_for_script(&mut self, _: &Script) -> FxHashSet<Id> {
-        self.preserved.clone()
-    }
-
     fn new_name_for(&self, _: &Id, n: &mut usize) -> Atom {
         self.chars.encode(n, true)
     }
@@ -91,6 +84,18 @@ impl Renamer for ManglingRenamer {
             cacher.update_vars_cache(update);
         }
     }
+
+    fn unresolved_symbols(&self) -> Vec<Atom> {
+        self.reserved
+            .iter()
+            .cloned()
+            .chain(self.preserved.iter().map(|id| id.0.clone()))
+            .collect()
+    }
+
+    fn preserve_name(&self, orig: &Id) -> bool {
+        self.preserved.contains(orig)
+    }
 }
 
 struct LabelMangler {

crates/swc_ecma_transforms_base/src/hygiene/mod.rs

@@ -1,5 +1,3 @@
-use rustc_hash::FxHashSet;
-use swc_atoms::Atom;
 use swc_common::Mark;
 use swc_ecma_ast::*;
 use swc_ecma_utils::stack_size::maybe_grow_default;
@@ -22,9 +20,6 @@ pub struct Config {
 
     /// Mangle even if vars are visible to `eval` or `with`.
     pub ignore_eval: bool,
-
-    /// Used for preventing mangler from renaming variables to reserved names.
-    pub preserved_symbols: FxHashSet<Atom>,
 }
 
 /// See [hygiene_with_config] for doc. Creates a `hygiene` pass with default

crates/swc_ecma_transforms_base/src/rename/analyzer/scope.rs

@@ -149,7 +149,8 @@ impl Scope {
         let mut n = 0;
 
         for id in queue {
-            if preserved.contains(&id)
+            if renamer.preserve_name(&id)
+                || preserved.contains(&id)
                 || to.get(&id).is_some()
                 || previous.get(&id).is_some()
                 || id.0 == "eval"
@@ -288,7 +289,8 @@ impl Scope {
         let mut n = 0;
 
         for id in queue {
-            if preserved.contains(&id)
+            if renamer.preserve_name(&id)
+                || preserved.contains(&id)
                 || to.get(&id).is_some()
                 || previous.get(&id).is_some()
                 || id.0 == "eval"

crates/swc_ecma_transforms_base/src/rename/mod.rs

@@ -34,14 +34,6 @@ pub trait Renamer: Send + Sync {
     /// It should be true if you expect lots of collisions
     const MANGLE: bool;
 
-    fn preserved_ids_for_module(&mut self, _: &Module) -> FxHashSet<Id> {
-        Default::default()
-    }
-
-    fn preserved_ids_for_script(&mut self, _: &Script) -> FxHashSet<Id> {
-        Default::default()
-    }
-
     fn get_cached(&self) -> Option<Cow<RenameMap>> {
         None
     }
@@ -50,6 +42,16 @@ pub trait Renamer: Send + Sync {
 
     /// Should increment `n`.
     fn new_name_for(&self, orig: &Id, n: &mut usize) -> Atom;
+
+    fn unresolved_symbols(&self) -> Vec<Atom> {
+        Default::default()
+    }
+
+    /// Return true if the identifier should be preserved.
+    #[inline]
+    fn preserve_name(&self, _orig: &Id) -> bool {
+        false
+    }
 }
 
 pub type RenameMap = FxHashMap<Id, Atom>;
@@ -175,10 +177,12 @@ where
                 .extend(self.preserved.iter().map(|v| v.0.clone()));
         }
 
-        if !self.config.preserved_symbols.is_empty() {
-            unresolved
-                .to_mut()
-                .extend(self.config.preserved_symbols.iter().cloned());
+        {
+            let extra_unresolved = self.renamer.unresolved_symbols();
+
+            if !extra_unresolved.is_empty() {
+                unresolved.to_mut().extend(extra_unresolved);
+            }
         }
 
         if R::MANGLE {
@@ -347,8 +351,6 @@ where
     fn visit_mut_module(&mut self, m: &mut Module) {
         self.load_cache();
 
-        self.preserved = self.renamer.preserved_ids_for_module(m);
-
         let has_eval = !self.config.ignore_eval && contains_eval(m, true);
 
         self.unresolved = self.get_unresolved(m, has_eval);
@@ -392,8 +394,6 @@ where
     fn visit_mut_script(&mut self, m: &mut Script) {
         self.load_cache();
 
-        self.preserved = self.renamer.preserved_ids_for_script(m);
-
         let has_eval = !self.config.ignore_eval && contains_eval(m, true);
 
         self.unresolved = self.get_unresolved(m, has_eval);