added ffmpeg resolution test

.flake8

@@ -1,5 +1,5 @@
 [flake8]
 ignore = E231,E203,W503,Q000,WPS111,WPS305,WPS348,WPS602,D400,DAR201,S101,DAR101,C812,D104,I001,WPS306,WPS214,D401,WPS229,WPS420,WPS230,WPS414,WPS114,WPS226,WPS442,C819,WPS601,T001,RST304,WPS410,WPS428,A003,A002,I003,WPS221,WPS326,WPS201,S405,DAR301,WPS210,WPS202,WPS213,WPS301,P103,WPS407,WPS432,WPS211,S314,S310,S001,IF100,PT001
-max-line-length = 89
+max-line-length = 94
 
 [isort]

tests/test_cli.py

@@ -253,6 +253,25 @@ def test_ffmpeg_process_best_should_download(_ffmpeg_downloader, youtube):
     )
 
 
+@mock.patch("pytube.cli.YouTube")
+@mock.patch("pytube.cli._ffmpeg_downloader")
+def test_ffmpeg_process_res_should_download(_ffmpeg_downloader, youtube):
+    # Given
+    target = "/target"
+    streams = MagicMock()
+    youtube.streams = streams
+    video_stream = MagicMock()
+    streams.filter.return_value.first.return_value = video_stream
+    audio_stream = MagicMock()
+    streams.get_audio_only.return_value = audio_stream
+    # When
+    cli.ffmpeg_process(youtube, "XYZp", target)
+    # Then
+    _ffmpeg_downloader.assert_called_with(
+        audio_stream=audio_stream, video_stream=video_stream, target=target
+    )
+
+
 @mock.patch("pytube.cli.YouTube.__init__", return_value=None)
 def test_download_audio(youtube):
     parser = argparse.ArgumentParser()