fix(transformer/arrow-functions): store super_methods on a Stack …

…to fix nested async methods (#8331)

In the following case, async methods can be nested in another async method. The implementation is changing to store `super_methods` on a stack, and then we can store super method information in the correct `super_methods` map.

```js
const outer = {
  value: 0,
  async method() {
    () => super.value;

    const inner = {
      value: 0,
      async method() {
        () => super.value;
      }
    };

    () => super.value;
  }
};
```

crates/oxc_transformer/src/common/arrow_function_converter.rs

@@ -93,7 +93,7 @@ use rustc_hash::{FxBuildHasher, FxHashSet};
 
 use oxc_allocator::{Box as ArenaBox, Vec as ArenaVec};
 use oxc_ast::{ast::*, visit::walk_mut::walk_expression, VisitMut, NONE};
-use oxc_data_structures::stack::{NonEmptyStack, SparseStack};
+use oxc_data_structures::stack::{NonEmptyStack, SparseStack, Stack};
 use oxc_semantic::{ReferenceFlags, SymbolId};
 use oxc_span::{CompactStr, GetSpan, SPAN};
 use oxc_syntax::{
@@ -144,7 +144,7 @@ pub struct ArrowFunctionConverter<'a> {
     renamed_arguments_symbol_ids: FxHashSet<SymbolId>,
     // TODO(improve-on-babel): `FxHashMap` would suffice here. Iteration order is not important.
     // Only using `FxIndexMap` for predictable iteration order to match Babel's output.
-    super_methods: Option<FxIndexMap<SuperMethodKey<'a>, SuperMethodInfo<'a>>>,
+    super_methods_stack: Stack<FxIndexMap<SuperMethodKey<'a>, SuperMethodInfo<'a>>>,
 }
 
 impl ArrowFunctionConverter<'_> {
@@ -164,7 +164,7 @@ impl ArrowFunctionConverter<'_> {
             constructor_super_stack: NonEmptyStack::new(false),
             arguments_needs_transform_stack: NonEmptyStack::new(false),
             renamed_arguments_symbol_ids: FxHashSet::default(),
-            super_methods: None,
+            super_methods_stack: Stack::new(),
         }
     }
 }
@@ -210,7 +210,7 @@ impl<'a> Traverse<'a> for ArrowFunctionConverter<'a> {
         self.constructor_super_stack.push(false);
         if self.is_async_only() && func.r#async && Self::is_class_method_like_ancestor(ctx.parent())
         {
-            self.super_methods = Some(FxIndexMap::default());
+            self.super_methods_stack.push(FxIndexMap::default());
         }
     }
 
@@ -617,7 +617,7 @@ impl<'a> ArrowFunctionConverter<'a> {
     /// whose body includes the original `super` expression. The arrow function's name
     /// is generated based on the property name, such as `_superprop_getProperty`.
     ///
-    /// The `super` expressions are temporarily stored in [`Self::super_methods`]
+    /// The `super` expressions are temporarily stored in [`Self::super_methods_stack`]
     /// and eventually inserted by [`Self::insert_variable_statement_at_the_top_of_statements`].`
     ///
     /// ## Example
@@ -640,7 +640,7 @@ impl<'a> ArrowFunctionConverter<'a> {
         assign_value: Option<&mut Expression<'a>>,
         ctx: &mut TraverseCtx<'a>,
     ) -> Option<Expression<'a>> {
-        let super_methods = self.super_methods.as_mut()?;
+        let super_methods = self.super_methods_stack.last_mut()?;
 
         let mut argument = None;
         let mut property = "";
@@ -718,7 +718,7 @@ impl<'a> ArrowFunctionConverter<'a> {
         call: &mut CallExpression<'a>,
         ctx: &mut TraverseCtx<'a>,
     ) -> Option<Expression<'a>> {
-        if self.super_methods.is_none() || !call.callee.is_member_expression() {
+        if self.super_methods_stack.last().is_none() || !call.callee.is_member_expression() {
             return None;
         }
 
@@ -757,7 +757,7 @@ impl<'a> ArrowFunctionConverter<'a> {
         ctx: &mut TraverseCtx<'a>,
     ) -> Option<Expression<'a>> {
         // Check if the left of the assignment is a `super` member expression.
-        if self.super_methods.is_none()
+        if self.super_methods_stack.last().is_none()
             || !assignment.left.as_member_expression().is_some_and(|m| m.object().is_super())
         {
             return None;
@@ -1050,10 +1050,11 @@ impl<'a> ArrowFunctionConverter<'a> {
         let arguments = self.create_arguments_var_declarator(target_scope_id, arguments_var, ctx);
 
         let is_class_method_like = Self::is_class_method_like_ancestor(ctx.parent());
-        let super_method_count = self.super_methods.as_ref().map_or(0, FxIndexMap::len);
-        let declarations_count = usize::from(arguments.is_some())
-            + if is_class_method_like { super_method_count } else { 0 }
-            + usize::from(this_var.is_some());
+        let super_methods =
+            if is_class_method_like { self.super_methods_stack.pop() } else { None };
+        let super_method_count = super_methods.as_ref().map_or(0, FxIndexMap::len);
+        let declarations_count =
+            usize::from(arguments.is_some()) + super_method_count + usize::from(this_var.is_some());
 
         // Exit if no declarations to be inserted
         if declarations_count == 0 {
@@ -1070,8 +1071,8 @@ impl<'a> ArrowFunctionConverter<'a> {
         // `_superprop_setSomething = _value => super.something = _value;`
         // `_superprop_set = (_prop, _value) => super[_prop] = _value;`
         if is_class_method_like {
-            if let Some(super_methods) = self.super_methods.as_mut() {
-                declarations.extend(super_methods.drain(..).map(|(key, super_method)| {
+            if let Some(super_methods) = super_methods {
+                declarations.extend(super_methods.into_iter().map(|(key, super_method)| {
                     Self::generate_super_method(
                         target_scope_id,
                         super_method,

tasks/coverage/snapshots/semantic_misc.snap

@@ -42,19 +42,19 @@ after transform: ScopeId(0): ["BrowserWorkingCopyBackupTracker", "CancellationTo
 rebuilt        : ScopeId(0): ["BrowserWorkingCopyBackupTracker", "DisposableStore", "EditorService", "IEditorGroupsService", "IEditorService", "IFilesConfigurationService", "ILifecycleService", "ILogService", "IWorkingCopyBackupService", "IWorkingCopyEditorService", "IWorkingCopyService", "InMemoryTestWorkingCopyBackupService", "LifecyclePhase", "Schemas", "TestServiceAccessor", "TestWorkingCopy", "URI", "UntitledTextEditorInput", "VSBuffer", "_asyncToGenerator", "_defineProperty", "assert", "bufferToReadable", "createEditorPart", "ensureNoDisposablesAreLeakedInTestSuite", "isWindows", "registerTestResourceEditor", "timeout", "toResource", "toTypedWorkingCopyId", "toUntypedWorkingCopyId", "workbenchInstantiationService", "workbenchTeardown"]
 Symbol reference IDs mismatch for "URI":
 after transform: SymbolId(1): [ReferenceId(109), ReferenceId(117), ReferenceId(156), ReferenceId(158), ReferenceId(160), ReferenceId(162)]
-rebuilt        : SymbolId(1): [ReferenceId(161), ReferenceId(163), ReferenceId(165), ReferenceId(167)]
+rebuilt        : SymbolId(1): [ReferenceId(160), ReferenceId(162), ReferenceId(164), ReferenceId(166)]
 Symbol reference IDs mismatch for "IEditorService":
 after transform: SymbolId(2): [ReferenceId(23), ReferenceId(24), ReferenceId(67), ReferenceId(184)]
-rebuilt        : SymbolId(2): [ReferenceId(17), ReferenceId(60), ReferenceId(188)]
+rebuilt        : SymbolId(2): [ReferenceId(17), ReferenceId(59), ReferenceId(187)]
 Symbol reference IDs mismatch for "IEditorGroupsService":
 after transform: SymbolId(4): [ReferenceId(25), ReferenceId(26), ReferenceId(57), ReferenceId(176)]
-rebuilt        : SymbolId(3): [ReferenceId(18), ReferenceId(51), ReferenceId(181)]
+rebuilt        : SymbolId(3): [ReferenceId(18), ReferenceId(50), ReferenceId(180)]
 Symbol reference IDs mismatch for "EditorService":
 after transform: SymbolId(5): [ReferenceId(61), ReferenceId(64), ReferenceId(178), ReferenceId(181)]
-rebuilt        : SymbolId(4): [ReferenceId(57), ReferenceId(185)]
+rebuilt        : SymbolId(4): [ReferenceId(56), ReferenceId(184)]
 Symbol reference IDs mismatch for "IWorkingCopyBackupService":
 after transform: SymbolId(7): [ReferenceId(11), ReferenceId(12), ReferenceId(51), ReferenceId(170)]
-rebuilt        : SymbolId(5): [ReferenceId(11), ReferenceId(45), ReferenceId(175)]
+rebuilt        : SymbolId(5): [ReferenceId(11), ReferenceId(44), ReferenceId(174)]
 Symbol reference IDs mismatch for "IFilesConfigurationService":
 after transform: SymbolId(10): [ReferenceId(13), ReferenceId(14)]
 rebuilt        : SymbolId(8): [ReferenceId(12)]
@@ -72,19 +72,19 @@ after transform: SymbolId(17): [ReferenceId(38), ReferenceId(87)]
 rebuilt        : SymbolId(13): [ReferenceId(31)]
 Symbol reference IDs mismatch for "InMemoryTestWorkingCopyBackupService":
 after transform: SymbolId(19): [ReferenceId(43), ReferenceId(46), ReferenceId(165)]
-rebuilt        : SymbolId(15): [ReferenceId(40), ReferenceId(170)]
+rebuilt        : SymbolId(15): [ReferenceId(39), ReferenceId(169)]
 Symbol reference IDs mismatch for "TestServiceAccessor":
 after transform: SymbolId(21): [ReferenceId(1), ReferenceId(40), ReferenceId(71), ReferenceId(155), ReferenceId(188)]
-rebuilt        : SymbolId(17): [ReferenceId(64), ReferenceId(192)]
+rebuilt        : SymbolId(17): [ReferenceId(63), ReferenceId(191)]
 Symbol reference IDs mismatch for "IWorkingCopyEditorService":
 after transform: SymbolId(32): [ReferenceId(21), ReferenceId(22)]
 rebuilt        : SymbolId(26): [ReferenceId(16)]
 Symbol reference IDs mismatch for "TestWorkingCopyBackupTracker":
 after transform: SymbolId(39): [ReferenceId(42), ReferenceId(74), ReferenceId(154), ReferenceId(215)]
-rebuilt        : SymbolId(35): [ReferenceId(67), ReferenceId(219)]
+rebuilt        : SymbolId(35): [ReferenceId(66), ReferenceId(218)]
 Unresolved reference IDs mismatch for "Promise":
 after transform: [ReferenceId(36), ReferenceId(39), ReferenceId(82), ReferenceId(114), ReferenceId(153), ReferenceId(282)]
-rebuilt        : [ReferenceId(292)]
+rebuilt        : [ReferenceId(291)]
 
 tasks/coverage/misc/pass/oxc-4449.ts
 semantic error: Bindings mismatch:

tasks/transform_conformance/snapshots/oxc.snap.md

@@ -1,6 +1,6 @@
 commit: 54a8389f
 
-Passed: 122/141
+Passed: 123/141
 
 # All Passed:
 * babel-plugin-transform-class-static-block
@@ -9,6 +9,7 @@ Passed: 122/141
 * babel-plugin-transform-optional-catch-binding
 * babel-plugin-transform-async-generator-functions
 * babel-plugin-transform-object-rest-spread
+* babel-plugin-transform-async-to-generator
 * babel-plugin-transform-exponentiation-operator
 * babel-plugin-transform-arrow-functions
 * babel-preset-typescript
@@ -45,11 +46,6 @@ after transform: SymbolId(0): [ReferenceId(0), ReferenceId(2), ReferenceId(6), R
 rebuilt        : SymbolId(0): [ReferenceId(0), ReferenceId(2), ReferenceId(6), ReferenceId(10)]
 
 
-# babel-plugin-transform-async-to-generator (17/18)
-* super/nested/input.js
-x Output mismatch
-
-
 # babel-plugin-transform-typescript (2/10)
 * class-property-definition/input.ts
 Unresolved references mismatch: