public function saveKeepsQuotedKey()
{
$pathAndFilename = vfsStream::url('testDirectory') . '/YAMLConfiguration';
$configurationSource = new YamlSource();
$mockConfiguration = array('configurationFileHasBeenLoaded' => true, 'foo' => array('Foo.Bar:Baz' => 'a quoted key'));
$configurationSource->save($pathAndFilename, $mockConfiguration);
$yaml = 'configurationFileHasBeenLoaded: true' . chr(10) . 'foo:' . chr(10) . ' \'Foo.Bar:Baz\': \'a quoted key\'' . chr(10);
$this->assertContains($yaml, file_get_contents($pathAndFilename . '.yaml'), 'Configuration was not written to the file as expected.');
}