diff --git a/turbopack/crates/turbopack-tests/tests/execution/turbopack/scope-hoisting/pure-comments/input/index.js b/turbopack/crates/turbopack-tests/tests/execution/turbopack/scope-hoisting/pure-comments/input/index.js
index 2b60f2c51b..66579eaf3d 100644
--- a/turbopack/crates/turbopack-tests/tests/execution/turbopack/scope-hoisting/pure-comments/input/index.js
+++ b/turbopack/crates/turbopack-tests/tests/execution/turbopack/scope-hoisting/pure-comments/input/index.js
@@ -1,13 +1,20 @@
 import './a.ts'
 
 it('should retain PURE comments with scope hoisting', () => {
-  let factory = __turbopack_modules__.get(
-    [...__turbopack_modules__.keys()].find((m) =>
-      m.endsWith(
-        'scope-hoisting/pure-comments/input/index.js [test] (ecmascript)'
-      )
+  const moduleKey = [...__turbopack_modules__.keys()].find((m) =>
+    m.endsWith(
+      'scope-hoisting/pure-comments/input/index.js [test] (ecmascript)'
     )
   )
+  
+  if (!moduleKey) {
+    throw new Error(
+      'Could not find module with key ending in "scope-hoisting/pure-comments/input/index.js [test] (ecmascript)". Available modules: ' +
+        Array.from(__turbopack_modules__.keys()).join(', ')
+    )
+  }
+  
+  let factory = __turbopack_modules__.get(moduleKey)
 
   expect(factory.toString()).not.toContain('THIS_SHOULD_BE_REMOVED')
 })

Analysis

The original test code had a critical error handling issue:

1. The Problem: The code called [...__turbopack_modules__.keys()].find((m) => m.endsWith(...)) and immediately passed the result to .get() without checking if .find() returned undefined.

2. Why It Fails: If no module key matches the endsWith condition (which could happen if the module key format doesn't match expectations), .find() returns undefined. Then .get(undefined) is called, which would return undefined, and calling .toString() on undefined would throw a TypeError: "Cannot read property 'toString' of undefined".

3. Root Cause: The test had two potential failure points:

   • The hardcoded string 'scope-hoisting/pure-comments/input/index.js [test] (ecmascript)' could fail to match the actual module key format
   • Even if the string matched, there was no defensive check for when .find() returns undefined

4. The Fix: The fix extracts the result of .find() into a moduleKey variable, adds an explicit null check, and provides a detailed error message that lists all available modules if the expected module is not found. This makes the test fail gracefully with useful debugging information instead of a confusing TypeError.

This is important because it:

• Prevents TypeError at runtime when module lookup fails
• Provides clear error messages for debugging when the expected module is not found
• Makes the test more robust to changes in module key format
• Follows defensive programming principles for external module access

diff --git a/turbopack/crates/turbopack-tests/tests/execution/turbopack/scope-hoisting/pure-comments/options.json b/turbopack/crates/turbopack-tests/tests/execution/turbopack/scope-hoisting/pure-comments/options.json
index 3dc1021aa8..4e71b0cc33 100644
--- a/turbopack/crates/turbopack-tests/tests/execution/turbopack/scope-hoisting/pure-comments/options.json
+++ b/turbopack/crates/turbopack-tests/tests/execution/turbopack/scope-hoisting/pure-comments/options.json
@@ -1,3 +1,4 @@
 {
-  "minify": true
+  "minify": true,
+  "remove_unused_exports": false
 }

Analysis

The test "should retain PURE comments with scope hoisting" in /turbopack/crates/turbopack-tests/tests/execution/turbopack/scope-hoisting/pure-comments/input/index.js has a logic flaw:

The Issue:

1. The test imports ./a.ts which exports an unused enum Unused with a member THIS_SHOULD_BE_REMOVED
2. The import statement has no destructuring/usage of the enum
3. The test checks that the string 'THIS_SHOULD_BE_REMOVED' doesn't appear in the compiled factory
4. The default test options have remove_unused_exports: true (from TestOptions::default())
5. This means unused exports are removed before scope hoisting processes the module

Why it's a problem:

• The test is meant to verify that PURE comments are retained during scope hoisting
• If the enum is completely tree-shaken away before scope hoisting, the string won't appear in the output
• But this would be for the WRONG reason - not because PURE comments are being preserved, but because the code was removed entirely
• The test would pass even if PURE comments were being incorrectly stripped during scope hoisting

The Fix:
Modified options.json to set "remove_unused_exports": false, which ensures:

1. The enum in a.ts is kept in the bundle despite being unused
2. Scope hoisting will actually process the module
3. The test correctly verifies that PURE comments (if any) are preserved during scope hoisting
4. The test now fails if PURE comments are incorrectly stripped

This fix ensures the test actually validates the intended behavior instead of passing for an accidental reason.