Deprecate the download argument. Fixes #38

tests/test_cli.py

@@ -0,0 +1,13 @@
+import pytest
+from humblebundle_downloader.cli import parse_args
+
+
+def test_old_action_format():
+    with pytest.raises(DeprecationWarning):
+        _ = parse_args(['download', '-l', 'some_path', '-c', 'fake_cookie'])
+
+
+def test_no_action():
+    args = parse_args(['-l', 'some_path', '-c', 'fake_cookie'])
+    assert args.library_path == 'some_path'
+    assert args.cookie_file == 'fake_cookie'