Increase coverage (#218)

* Monkeypatch fetch user and use pytest.tempdir

* Cover spotify_tools.grab_album()

* Cover avconv conversion

* Cover grab_single()

* Reduce code repetition

* Move grab_playlist() to spotify_tools.py

* Move Spotify specific functions to spotify_tools.py

* Refactoring

* Return track list from write_tracks()

* Fix tests

* Cover more cases in generate_youtube_url()

* Test for unavailable audio streams

* Test for filename without spaces

* handle.py 100% coverage

* Improve config tests

* Speed up tests

* Install avconv and libfdk-aac

* Some cleaning

* FFmpeg with libfdk-aac, libopus

* Some refactoring

* Convert tmpdir to string

* Cover YouTube title when downloading from list

* Explicitly cover some internals.py functions

test/test_internals.py

@@ -0,0 +1,38 @@
+from core import internals
+
+import os
+
+
+class TestPathFilterer:
+    def test_create_directory(self, tmpdir):
+        expect_path = True
+        global folder_path
+        folder_path = os.path.join(str(tmpdir), 'filter_this_folder')
+        internals.filter_path(folder_path)
+        is_path = os.path.isdir(folder_path)
+        assert is_path == expect_path
+
+    def test_remove_temp_files(self, tmpdir):
+        expect_file = False
+        file_path = os.path.join(folder_path, 'pesky_file.temp')
+        open(file_path, 'a')
+        internals.filter_path(folder_path)
+        is_file = os.path.isfile(file_path)
+        assert is_file == expect_file
+
+
+class TestVideoTime:
+    def test_from_seconds(self):
+        expect_duration = '35'
+        duration = internals.videotime_from_seconds(35)
+        assert duration == expect_duration
+
+    def test_from_minutes(self):
+        expect_duration = '2:38'
+        duration = internals.videotime_from_seconds(158)
+        assert duration == expect_duration
+
+    def test_from_hours(self):
+        expect_duration = '1:16:02'
+        duration = internals.videotime_from_seconds(4562)
+        assert duration == expect_duration