Bug in \yii\redis\Connection (it closes connection after serialize)

[IStranger]

What steps will reproduce the problem?

Enable Redis cache in config:

'components' => [
    'cache' => [
        'class' => 'yii\redis\Cache',
    ],
],

Then execute:

error_reporting(E_ERROR);

Yii::$app->cache->set('someKey', 'someValue');

$print = VarDumper::export(Yii::$app->cache);        // This will close redis connection
// $print = serialize(Yii::$app->cache);                // This will close redis connection
// $print = var_export(Yii::$app->cache, true);         // This won't close redis connection

$cachedValue = Yii::$app->cache->get('someKey');        // This won't work at closed redis connection:

//   error_reporting(E_ERROR) :: >> Database Exception – yii\db\Exception::: Failed to read from socket. Redis command was: GET keyPrefix:someKey
//   error_reporting(E_ALL)   :: >> PHP Warning – yii\base\ErrorException::: fwrite() expects parameter 1 to be resource, null given

What is the expected result?

Redis connection closes connection at serializing. This is normal behavior (see \yii\redis\Connection::__sleep).
However after serializing cache component won't work. I think redis connection should be restored.

Additional info

Q	A
Yii version	2.0.9
PHP version	5.5.34
Operating system	Mac OS X 10.11.5

[yii-bot]

Issue moved to yiisoft/yii2-redis#87