added unit tests and made keyword arguments more consistent

tests/api.py

@@ -0,0 +1,44 @@
+# -*- coding: UTF-8 -*-
+
+"""Tests for to polyphemus.api module.
+
+The full set of tests for this module can be evaluated by executing the
+command::
+
+  $ python -m pytest tests/api.py
+
+from the project root directory.
+
+"""
+
+#+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++#
+
+import pytest
+
+from polyphemus import api
+
+#+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++#
+
+KWARGS_LIST = [
+    ('get_channel_info', ['channel_name']),
+    ('get_subscribers', ['channel_id']),
+    ('get_all_videos', ['channel_id']),
+    ('get_views', ['video_id']),
+    ('get_video_reactions', ['video_id']),
+    ('get_all_comments', ['video_id']),
+    ('append_comment_reactions', ['comment_info_list']),
+    ('normalized_name_to_video_info', ['normalized_name']),
+    ('get_streaming_url', ['canonical_url']),
+    ('get_recommended', ['video_title', 'video_id']),]
+
+#+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++#
+
+@pytest.mark.parametrize( 'function_str,kwargs', KWARGS_LIST )
+def test_minimal_init( resources, function_str, kwargs ):
+
+  function = eval( f'api.{function_str}')
+  function_kwargs = { kwarg : resources[ kwarg ] for kwarg in kwargs }
+
+  function( **function_kwargs )
+
+#+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++#