public function testFlushContentClearsKey()
{
$cache = $this->getMock('Swift_KeyCache');
$cache->expects($this->once())->method('clearKey')->with($this->_nsKey, 'foo');
$stream = new Swift_KeyCache_SimpleKeyCacheInputStream();
$stream->setKeyCache($cache);
$stream->setNsKey($this->_nsKey);
$stream->setItemKey('foo');
$stream->flushBuffers();
}