add test. fix typos.

tests/test_downloader.py

@@ -200,3 +200,20 @@ def test_download_submission(
     RedditDownloader._download_submission(downloader_mock, submission)
     folder_contents = list(tmp_path.iterdir())
     assert len(folder_contents) == expected_files_len
+
+
+@pytest.mark.parametrize('test_ignore_user', (
+    'alice',
+))
+def test_download_ignores_user(
+        test_ignore_user: str,
+        mock_function: MagicMock,
+        downloader_mock: MagicMock,
+):
+    downloader_mock.args.ignore_user = test_ignore_user
+    submission = downloader_mock.reddit_instance.submission(id='m1hqw6')
+    mock_function.return_value = MagicMock()
+    mock_function.return_value.__name__ = 'test'
+    submission.author.name = test_ignore_user
+    RedditDownloader._download_submission(downloader_mock, submission)
+    assert mock_function.call_count == 0