Check for wrong venv path in cache

.github/workflows/test-cache.yml

@@ -20,7 +20,6 @@ jobs:
       - name: Setup with cache
         uses: ./
         with:
-          version: '0.11.0'
           enable-cache: true
           working-directory: __tests__/fixtures/rye-project
           cache-prefix: ${{ github.run_id }}-${{ github.run_attempt }}
@@ -38,7 +37,6 @@ jobs:
         id: restore
         uses: ./
         with:
-            version: '0.11.0'
             enable-cache: true
             working-directory: __tests__/fixtures/rye-project
             cache-prefix: ${{ github.run_id }}-${{ github.run_attempt }}
@@ -65,16 +63,52 @@ jobs:
           cache-local-storage-path: /tmp/rye-cache
       - run: rye sync
         working-directory: __tests__/fixtures/rye-project
+  test-restore-cache-local:
+    runs-on: oracle-aarch64
+    needs: test-setup-cache-local
+    steps:
+      - uses: actions/checkout@v4
+      - name: Restore with cache
+        id: restore
+        uses: ./
+        with:
+            enable-cache: true
+            working-directory: __tests__/fixtures/rye-project
+            cache-prefix: ${{ github.run_id }}-${{ github.run_attempt }}
+            cache-local-storage-path: /tmp/rye-cache
+      - name: Cache was hit
+        run: |
+          if [ "$CACHE_HIT" != "true" ]; then
+            exit 1
+          fi
+        env:
+          CACHE_HIT: ${{ steps.restore.outputs.cache-hit }}
+      - run: rye sync
+        working-directory: __tests__/fixtures/rye-project
+
+  test-setup-cache-local-venv-path-mismatch:
+    runs-on: oracle-aarch64
+    steps:
+      - uses: actions/checkout@v4
+      - name: Setup with cache
+        uses: ./
+        with:
+          enable-cache: true
+          working-directory: __tests__/fixtures/rye-project
+          cache-prefix: ${{ github.run_id }}-${{ github.run_attempt }}-path-mismatch
+          cache-local-storage-path: /tmp/rye-cache
+      - run: rye sync
+        working-directory: __tests__/fixtures/rye-project
   alter-venv-path-in-cache-local:
     runs-on: oracle-aarch64
     needs: test-setup-cache-local
     steps:
       - uses: actions/checkout@v4
       - name: Alter venv path in cache
         run: |
-          RYE_VENV_PATH=$(find /tmp/rye-cache -type f -name 'rye-venv.json' -path '/tmp/rye-cache/${{ github.run_id }}-${{ github.run_attempt }}*')
+          RYE_VENV_PATH=$(find /tmp/rye-cache -type f -name 'rye-venv.json' -path '/tmp/rye-cache/${{ github.run_id }}-${{ github.run_attempt }}-path-mismatch*')
           sed -i 's/"venv_path":\s*"[^"]*"/"venv_path": "something"/' "$RYE_VENV_PATH"
-  test-restore-cache-local:
+  test-restore-cache-local-venv-path-mismatch:
     runs-on: oracle-aarch64
     needs: alter-venv-path-in-cache-local
     steps:
@@ -85,14 +119,14 @@ jobs:
         with:
             enable-cache: true
             working-directory: __tests__/fixtures/rye-project
-            cache-prefix: ${{ github.run_id }}-${{ github.run_attempt }}
+            cache-prefix: ${{ github.run_id }}-${{ github.run_attempt }}-path-mismatch
             cache-local-storage-path: /tmp/rye-cache
-      - name: Cache was hit
+      - name: Cache was not hit
         run: |
-          if [ "$CACHE_HIT" != "true" ]; then
+          if [ "$CACHE_HIT" == "true" ]; then
             exit 1
           fi
         env:
           CACHE_HIT: ${{ steps.restore.outputs.cache-hit }}
       - run: rye sync
-        working-directory: __tests__/fixtures/rye-project
+        working-directory: __tests__/fixtures/rye-project

src/restore-cache.ts

@@ -62,34 +62,41 @@ function handleMatchResult(
   matchedKey: string | undefined,
   primaryKey: string
 ): void {
-  if (matchedKey) {
-    core.saveState(STATE_CACHE_MATCHED_KEY, matchedKey)
-    core.info(
-      `.venv restored from${cacheLocalStoragePath ? ' local' : ''} cache with key: ${matchedKey}`
-    )
-    overwriteCachedVenvPath()
-    core.setOutput('cache-hit', true)
-  } else {
+  if (!matchedKey) {
     core.info(
       `No${cacheLocalStoragePath ? ' local' : ''} cache found for key: ${primaryKey}`
     )
     core.setOutput('cache-hit', false)
+    return
+  }
+
+  const venvPathMatch = doesCachedVenvPathMatchCurrentVenvPath()
+  if (!venvPathMatch) {
+    fs.rmSync(venvPath, {recursive: true})
+    core.setOutput('cache-hit', false)
+    return
   }
+
+  core.saveState(STATE_CACHE_MATCHED_KEY, matchedKey)
+  core.info(
+    `.venv restored from${cacheLocalStoragePath ? ' local' : ''} cache with key: ${matchedKey}`
+  )
+  core.setOutput('cache-hit', true)
 }
 
-/**
- * Overwrite the cached venv path in rye-venv.json
- *
- * Rye prevents unwanted behavior if people copy around .venv between projects.
- * But we can be sure, that we are always working with the same project but the base path of previous runners might be different.
- */
-function overwriteCachedVenvPath(): void {
+function doesCachedVenvPathMatchCurrentVenvPath(): boolean {
   const ryeVenvPath = `${venvPath}/rye-venv.json`
-  let ryeVenv = JSON.parse(fs.readFileSync(ryeVenvPath, 'utf8'))
-  core.debug(`venv_path in cache: ${ryeVenv.venv_path}`)
-  core.debug(`Overwriting cached venv_path with ${venvPath}`)
-  ryeVenv.venv_path = venvPath
-  fs.writeFileSync(ryeVenvPath, JSON.stringify(ryeVenv))
+  const ryeVenv = JSON.parse(fs.readFileSync(ryeVenvPath, 'utf8'))
+  core.info(
+    `Checking if the cached .venv matches the current path: ${venvPath}`
+  )
+  if (ryeVenv.venv_path != venvPath) {
+    core.warning(
+      `The .venv in the cache cannot be used because it is from another location: ${ryeVenv.venv_path}`
+    )
+    return false
+  }
+  return true
 }
 
 async function restoreCacheLocal(