[8.x] Add test for FileStore (#40795)

* Add test for FileStore

* Add test for Increment in FileStore

Author: imanghafoori1

tests/Cache/CacheFileStoreTest.php

@@ -34,6 +34,21 @@ public function testNullIsReturnedIfFileDoesntExist()
         $this->assertNull($value);
     }
 
+    public function testUnserializableFileContentGetDeleted()
+    {
+        $files = $this->mockFilesystem();
+        $hash = sha1('foo');
+        $cachePath = __DIR__.'/'.substr($hash, 0, 2).'/'.substr($hash, 2, 2).'/'.$hash;
+
+        $files->expects($this->once())->method('get')->willReturn('9999999999-I_am_unserializableee: \(~_~)/');
+        $files->expects($this->once())->method('exists')->with($this->equalTo($cachePath))->willReturn(true);
+        $files->expects($this->once())->method('delete')->with($this->equalTo($cachePath));
+
+        $value = (new FileStore($files, __DIR__))->get('foo');
+
+        $this->assertNull($value);
+    }
+
     public function testPutCreatesMissingDirectories()
     {
         $files = $this->mockFilesystem();
@@ -149,6 +164,19 @@ public function testForeversAreNotRemovedOnIncrement()
         $this->assertSame('Hello World', $store->get('foo'));
     }
 
+    public function testIncrementCanAtomicallyJump()
+    {
+        $files = $this->mockFilesystem();
+        $initialValue = '9999999999'.serialize(1);
+        $valueAfterIncrement = '9999999999'.serialize(4);
+        $store = new FileStore($files, __DIR__);
+        $files->expects($this->once())->method('get')->willReturn($initialValue);
+        $hash = sha1('foo');
+        $cache_dir = substr($hash, 0, 2).'/'.substr($hash, 2, 2);
+        $files->expects($this->once())->method('put')->with($this->equalTo(__DIR__.'/'.$cache_dir.'/'.$hash), $this->equalTo($valueAfterIncrement));
+        $store->increment('foo', 3);
+    }
+
     public function testIncrementDoesNotExtendCacheLife()
     {
         $files = $this->mockFilesystem();