fix(transformer/arrow-functions): correct scope for _this (#5189)

The `_this` will eventually be inserted into a `Program` or `Function`. So we have to go up to the corresponding `scope_id`
oxc-project · Aug 25, 2024 · d9ba5ad · d9ba5ad
1 parent 056c667
commit d9ba5ad
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Showing 3 changed files with 11 additions and 114 deletions.
diff --git a/crates/oxc_transformer/src/es2015/arrow_functions.rs b/crates/oxc_transformer/src/es2015/arrow_functions.rs
@@ -217,8 +217,16 @@ impl<'a> ArrowFunctions<'a> {
     fn get_this_name(&mut self, ctx: &mut TraverseCtx<'a>) -> BoundIdentifier<'a> {
         let this_var = self.this_vars.last_mut().unwrap();
         if this_var.is_none() {
-            this_var.replace(BoundIdentifier::new_uid_in_current_scope(
+            let target_scope_id =
+                ctx.scopes().ancestors(ctx.current_scope_id()).skip(1).find(|scope_id| {
+                    let scope_flags = ctx.scopes().get_flags(*scope_id);
+                    scope_flags.intersects(ScopeFlags::Function | ScopeFlags::Top)
+                        && !scope_flags.contains(ScopeFlags::Arrow)
+                });
+
+            this_var.replace(BoundIdentifier::new_uid(
                 "this",
+                target_scope_id.unwrap(),
                 SymbolFlags::FunctionScopedVariable,
                 ctx,
             ));

diff --git a/tasks/transform_conformance/babel.snap.md b/tasks/transform_conformance/babel.snap.md
@@ -1,10 +1,11 @@
 commit: 12619ffe
 
-Passed: 280/953
+Passed: 281/953
 
 # All Passed:
 * babel-plugin-transform-optional-catch-binding
 * babel-plugin-transform-react-display-name
+* babel-plugin-transform-react-jsx-self
 * babel-plugin-transform-react-jsx-source
 
 
@@ -1918,35 +1919,11 @@ failed to resolve query: failed to parse the rest of input: ...''
 # babel-plugin-transform-arrow-functions (0/6)
 * assumption-newableArrowFunctions-false/basic/input.js
   x Output mismatch
-  x Bindings mismatch:
-  | after transform: ScopeId(1): ["f"]
-  | rebuilt        : ScopeId(1): ["_this2", "f"]
-
-  x Bindings mismatch:
-  | after transform: ScopeId(4): []
-  | rebuilt        : ScopeId(4): ["_this"]
-
-  x Bindings mismatch:
-  | after transform: ScopeId(5): ["_this"]
-  | rebuilt        : ScopeId(5): []
-
-  x Bindings mismatch:
-  | after transform: ScopeId(6): ["_this2"]
-  | rebuilt        : ScopeId(6): []
-
-  x Symbol scope ID mismatch:
-  | after transform: SymbolId(6): ScopeId(6)
-  | rebuilt        : SymbolId(1): ScopeId(1)
-
   x Symbol flags mismatch:
   | after transform: SymbolId(2): SymbolFlags(FunctionScopedVariable |
   | ArrowFunction)
   | rebuilt        : SymbolId(3): SymbolFlags(FunctionScopedVariable)
 
-  x Symbol scope ID mismatch:
-  | after transform: SymbolId(5): ScopeId(5)
-  | rebuilt        : SymbolId(6): ScopeId(4)
-
 
 * assumption-newableArrowFunctions-false/naming/input.js
   x Output mismatch
@@ -5948,30 +5925,6 @@ failed to resolve query: failed to parse the rest of input: ...''
 
 
 * react/arrow-functions/input.js
-  x Bindings mismatch:
-  | after transform: ScopeId(1): []
-  | rebuilt        : ScopeId(1): ["_this"]
-
-  x Bindings mismatch:
-  | after transform: ScopeId(2): ["_this"]
-  | rebuilt        : ScopeId(2): []
-
-  x Bindings mismatch:
-  | after transform: ScopeId(3): []
-  | rebuilt        : ScopeId(3): ["_this2"]
-
-  x Bindings mismatch:
-  | after transform: ScopeId(4): ["_this2"]
-  | rebuilt        : ScopeId(4): []
-
-  x Symbol scope ID mismatch:
-  | after transform: SymbolId(2): ScopeId(2)
-  | rebuilt        : SymbolId(1): ScopeId(1)
-
-  x Symbol scope ID mismatch:
-  | after transform: SymbolId(3): ScopeId(4)
-  | rebuilt        : SymbolId(3): ScopeId(3)
-
   x Unresolved references mismatch:
   | after transform: ["React", "this"]
   | rebuilt        : ["React"]
@@ -6125,30 +6078,6 @@ failed to resolve query: failed to parse the rest of input: ...''
 
 
 * react-automatic/arrow-functions/input.js
-  x Bindings mismatch:
-  | after transform: ScopeId(1): []
-  | rebuilt        : ScopeId(1): ["_this"]
-
-  x Bindings mismatch:
-  | after transform: ScopeId(2): ["_this"]
-  | rebuilt        : ScopeId(2): []
-
-  x Bindings mismatch:
-  | after transform: ScopeId(3): []
-  | rebuilt        : ScopeId(3): ["_this2"]
-
-  x Bindings mismatch:
-  | after transform: ScopeId(4): ["_this2"]
-  | rebuilt        : ScopeId(4): []
-
-  x Symbol scope ID mismatch:
-  | after transform: SymbolId(3): ScopeId(2)
-  | rebuilt        : SymbolId(2): ScopeId(1)
-
-  x Symbol scope ID mismatch:
-  | after transform: SymbolId(4): ScopeId(4)
-  | rebuilt        : SymbolId(4): ScopeId(3)
-
   x Unresolved references mismatch:
   | after transform: ["this"]
   | rebuilt        : []
@@ -6282,34 +6211,6 @@ transform-react-jsx: unknown field `autoImport`, expected one of `runtime`, `dev
 
 
 
-# babel-plugin-transform-react-jsx-self (2/3)
-* react-source/arrow-function/input.js
-  x Bindings mismatch:
-  | after transform: ScopeId(0): ["fn"]
-  | rebuilt        : ScopeId(0): ["_this", "fn"]
-
-  x Bindings mismatch:
-  | after transform: ScopeId(1): ["_this"]
-  | rebuilt        : ScopeId(1): []
-
-  x Bindings mismatch:
-  | after transform: ScopeId(2): []
-  | rebuilt        : ScopeId(2): ["_this2"]
-
-  x Bindings mismatch:
-  | after transform: ScopeId(3): ["_this2"]
-  | rebuilt        : ScopeId(3): []
-
-  x Symbol scope ID mismatch:
-  | after transform: SymbolId(1): ScopeId(1)
-  | rebuilt        : SymbolId(0): ScopeId(0)
-
-  x Symbol scope ID mismatch:
-  | after transform: SymbolId(2): ScopeId(3)
-  | rebuilt        : SymbolId(2): ScopeId(2)
-
-
-
 # babel-plugin-transform-react-jsx-development (6/10)
 * cross-platform/disallow-__self-as-jsx-attribute/input.js
   ! Duplicate __self prop found.

diff --git a/tasks/transform_conformance/oxc.snap.md b/tasks/transform_conformance/oxc.snap.md
@@ -8,18 +8,6 @@ Passed: 9/36
 
 # babel-plugin-transform-arrow-functions (0/1)
 * use-this-inside-blocks/input.js
-  x Bindings mismatch:
-  | after transform: ScopeId(1): []
-  | rebuilt        : ScopeId(1): ["_this"]
-
-  x Bindings mismatch:
-  | after transform: ScopeId(3): ["_this"]
-  | rebuilt        : ScopeId(3): []
-
-  x Symbol scope ID mismatch:
-  | after transform: SymbolId(3): ScopeId(3)
-  | rebuilt        : SymbolId(1): ScopeId(1)
-
   x Symbol flags mismatch:
   | after transform: SymbolId(1): SymbolFlags(BlockScopedVariable |
   | ArrowFunction)