From 90c74ee4498261b124f23bb3e3e7e0a186fe18a0 Mon Sep 17 00:00:00 2001
From: overlookmotel <557937+overlookmotel@users.noreply.github.com>
Date: Thu, 22 Aug 2024 23:40:26 +0000
Subject: [PATCH] fix(semantic): transform checker check reference symbol IDs
 (#5090)

Previously was checking that references point to symbols with same name, but not necessarily the same symbol (there could be 2 different symbols with same name).
---
 crates/oxc_semantic/src/post_transform_checker.rs | 14 +++++++++-----
 tasks/coverage/semantic_typescript.snap           |  3 +++
 2 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/crates/oxc_semantic/src/post_transform_checker.rs b/crates/oxc_semantic/src/post_transform_checker.rs
index 46cec1b4a..792d99b18 100644
--- a/crates/oxc_semantic/src/post_transform_checker.rs
+++ b/crates/oxc_semantic/src/post_transform_checker.rs
@@ -499,7 +499,6 @@ impl<'s> PostTransformChecker<'s> {
             return;
         }
 
-        // Check whether symbols match
         for reference_ids in self
             .after_transform
             .ids
@@ -509,13 +508,18 @@ impl<'s> PostTransformChecker<'s> {
             .zip(self.rebuilt.ids.reference_ids.iter().copied())
             .map(Pair::from_tuple)
         {
+            // Check symbol IDs match
             let symbol_ids = self.get_pair(reference_ids, |data, reference_id| {
                 data.symbols.references[reference_id].symbol_id()
             });
-            let symbol_names = self.get_pair(symbol_ids, |data, symbol_id| {
-                symbol_id.map(|symbol_id| data.symbols.names[symbol_id].clone())
-            });
-            if symbol_names.is_mismatch() {
+            let symbol_ids_remapped = Pair::new(
+                symbol_ids.after_transform.map(|symbol_id| self.symbol_ids_map.get(symbol_id)),
+                symbol_ids.rebuilt.map(Option::Some),
+            );
+            if symbol_ids_remapped.is_mismatch() {
+                let symbol_names = self.get_pair(symbol_ids, |data, symbol_id| {
+                    symbol_id.map(|symbol_id| data.symbols.names[symbol_id].clone())
+                });
                 self.errors.push_mismatch("Reference mismatch", reference_ids, symbol_names);
             }
         }
diff --git a/tasks/coverage/semantic_typescript.snap b/tasks/coverage/semantic_typescript.snap
index e5efd01c9..fccaa224a 100644
--- a/tasks/coverage/semantic_typescript.snap
+++ b/tasks/coverage/semantic_typescript.snap
@@ -21348,6 +21348,9 @@ rebuilt        : SymbolId(0): [ReferenceId(6)]
 Symbol reference IDs mismatch:
 after transform: SymbolId(3): [ReferenceId(1), ReferenceId(2), ReferenceId(3), ReferenceId(4), ReferenceId(5)]
 rebuilt        : SymbolId(1): [ReferenceId(0), ReferenceId(1), ReferenceId(2), ReferenceId(3), ReferenceId(4), ReferenceId(5)]
+Reference mismatch:
+after transform: ReferenceId(0): Some("E")
+rebuilt        : ReferenceId(4): Some("E")
 
 tasks/coverage/typescript/tests/cases/compiler/underscoreMapFirst.ts
 semantic error: Bindings mismatch: