/**
  * set up test environment
  */
 public function setUp()
 {
     $this->fooURL = vfsStream::url('foo');
     $this->barURL = vfsStream::url('foo/bar');
     $this->baz1URL = vfsStream::url('foo/bar/baz1');
     $this->baz2URL = vfsStream::url('foo/baz2');
     $this->foo = new vfsStreamDirectory('foo');
     $this->bar = new vfsStreamDirectory('bar');
     $this->baz1 = vfsStream::newFile('baz1')->lastModified(300)->lastAccessed(300)->lastAttributeModified(300)->withContent('baz 1');
     $this->baz2 = vfsStream::newFile('baz2')->withContent('baz2')->lastModified(400)->lastAccessed(400)->lastAttributeModified(400);
     $this->bar->addChild($this->baz1);
     $this->foo->addChild($this->bar);
     $this->foo->addChild($this->baz2);
     $this->foo->lastModified(100)->lastAccessed(100)->lastAttributeModified(100);
     $this->bar->lastModified(200)->lastAccessed(100)->lastAttributeModified(100);
     vfsStreamWrapper::register();
     vfsStreamWrapper::setRoot($this->foo);
 }