[11.x] Test for forgetting non-flexible keys for file driver

src/Illuminate/Cache/FileStore.php

@@ -248,9 +248,11 @@ public function restoreLock($name, $owner)
     public function forget($key)
     {
         if ($this->files->exists($file = $this->path($key))) {
-            $this->files->delete($this->path("illuminate:cache:flexible:created:{$key}"));
-
-            return $this->files->delete($file);
+            return tap($this->files->delete($file), function ($forgotten) use ($key) {
+                if ($forgotten && $this->files->exists($file = $this->path("illuminate:cache:flexible:created:{$key}"))) {
+                    $this->files->delete($file);
+                }
+            });
         }
 
         return false;

tests/Cache/CacheFileStoreTest.php

@@ -7,6 +7,7 @@
 use Illuminate\Contracts\Filesystem\FileNotFoundException;
 use Illuminate\Filesystem\Filesystem;
 use Illuminate\Support\Carbon;
+use Illuminate\Support\Str;
 use Mockery as m;
 use PHPUnit\Framework\TestCase;
 
@@ -330,6 +331,49 @@ public function testFlushIgnoreNonExistingDirectory()
         $this->assertFalse($result, 'Flush should not clean directory');
     }
 
+    public function testItHandlesForgettingNonFlexibleKeys()
+    {
+        $store = new FileStore(new Filesystem, __DIR__);
+
+        $key = Str::random();
+        $path = $store->path($key);
+        $flexiblePath = "illuminate:cache:flexible:created:{$key}";
+
+        $store->put($key, 'value', 5);
+
+        $this->assertFileExists($path);
+        $this->assertFileDoesNotExist($flexiblePath);
+
+        $store->forget($key);
+
+        $this->assertFileDoesNotExist($path);
+        $this->assertFileDoesNotExist($flexiblePath);
+    }
+
+    public function itOnlyForgetsFlexibleKeysIfParentIsForgotten()
+    {
+        $store = new FileStore(new Filesystem, __DIR__);
+
+        $key = Str::random();
+        $path = $store->path($key);
+        $flexiblePath = "illuminate:cache:flexible:created:{$key}";
+
+        touch($flexiblePath);
+
+        $this->assertFileDoesNotExist($path);
+        $this->assertFileExists($flexiblePath);
+
+        $store->forget($key);
+
+        $this->assertFileDoesNotExist($path);
+        $this->assertFileExists($flexiblePath);
+
+        $store->put($key, 'value', 5);
+
+        $this->assertFileDoesNotExist($path);
+        $this->assertFileDoesNotExist($flexiblePath);
+    }
+
     protected function mockFilesystem()
     {
         return $this->createMock(Filesystem::class);