diff --git a/framework/widgets/FragmentCache.php b/framework/widgets/FragmentCache.php
index 78eefd0cfe..2bd66f7c79 100644
--- a/framework/widgets/FragmentCache.php
+++ b/framework/widgets/FragmentCache.php
@@ -14,6 +14,7 @@ use yii\caching\Dependency;
 use yii\di\Instance;
 
 /**
+ * FragmentCache is used by [[yii\base\View]] to provide caching of page fragments.
  *
  * @property string|boolean $cachedContent The cached content. False is returned if valid content is not found
  * in the cache. This property is read-only.
diff --git a/tests/framework/widgets/FragmentCacheTest.php b/tests/framework/widgets/FragmentCacheTest.php
new file mode 100644
index 0000000000..fdaa7a2fbe
--- /dev/null
+++ b/tests/framework/widgets/FragmentCacheTest.php
@@ -0,0 +1,91 @@
+<?php
+
+namespace yiiunit\framework\widgets;
+
+use Yii;
+use yii\caching\ArrayCache;
+use yii\base\View;
+use yii\widgets\Breadcrumbs;
+
+/**
+ * @group widgets
+ * @group caching
+ */
+class FragmentCacheTest extends \yiiunit\TestCase
+{
+    protected function setUp()
+    {
+        parent::setUp();
+        $this->mockWebApplication();
+        Yii::$app->set('cache', [
+            'class' => ArrayCache::className(),
+        ]);
+    }
+
+    public function testCacheEnabled()
+    {
+        $expectedLevel = ob_get_level();
+        ob_start();
+        ob_implicit_flush(false);
+
+        $view = new View();
+        $this->assertTrue($view->beginCache('test'));
+        echo "cached fragment";
+        $view->endCache();
+
+        ob_start();
+        ob_implicit_flush(false);
+        $this->assertFalse($view->beginCache('test'));
+        $this->assertEquals("cached fragment", ob_get_clean());
+
+        ob_end_clean();
+        $this->assertEquals($expectedLevel, ob_get_level(), 'Output buffer not closed correctly.');
+    }
+
+    public function testCacheDisabled1()
+    {
+        $expectedLevel = ob_get_level();
+        ob_start();
+        ob_implicit_flush(false);
+
+        $view = new View();
+        $this->assertTrue($view->beginCache('test', ['enabled' => false]));
+        echo "cached fragment";
+        $view->endCache();
+
+        ob_start();
+        ob_implicit_flush(false);
+        $this->assertTrue($view->beginCache('test', ['enabled' => false]));
+        echo "cached fragment";
+        $view->endCache();
+        $this->assertEquals("cached fragment", ob_get_clean());
+
+        ob_end_clean();
+        $this->assertEquals($expectedLevel, ob_get_level(), 'Output buffer not closed correctly.');
+    }
+
+    public function testCacheDisabled2()
+    {
+        $expectedLevel = ob_get_level();
+        ob_start();
+        ob_implicit_flush(false);
+
+        $view = new View();
+        $this->assertTrue($view->beginCache('test'));
+        echo "cached fragment";
+        $view->endCache();
+
+        ob_start();
+        ob_implicit_flush(false);
+        $this->assertTrue($view->beginCache('test', ['enabled' => false]));
+        echo "cached fragment other";
+        $view->endCache();
+        $this->assertEquals("cached fragment other", ob_get_clean());
+
+        ob_end_clean();
+        $this->assertEquals($expectedLevel, ob_get_level(), 'Output buffer not closed correctly.');
+    }
+
+
+    // TODO test dynamic replacements
+}