public function testAddTracksToPlaylist()
 {
     $mockResponse = (object) ['snapshot_id' => 'abc123'];
     $tracksToAdd = ['some:track:uri', 'some:other:track', 'some:third:track'];
     $this->apiStub->method('getSpotifyUserId')->willReturn('foo');
     $this->apiStub->expects($this->once())->method('addUserPlaylistTracks')->with('foo', 'playlistId', $tracksToAdd)->willReturn($mockResponse);
     $result = $this->playlistManager->addTracksToPlaylist('playlistId', $tracksToAdd);
     $this->assertTrue($result);
 }
 /**
  * Adds new tracks to a playlist
  *
  * @param string $playlistId
  * @param array $tracks
  *
  * @return bool
  */
 public function addTracksToPlaylist($playlistId, array $tracks)
 {
     $userId = $this->spotifyWebApi->getSpotifyUserId();
     $this->spotifyWebApi->addUserPlaylistTracks($userId, $playlistId, $tracks);
     return true;
 }