Test coverage fixes

Author: pawelad

icon_font_to_png/command_line.py

@@ -154,7 +154,7 @@ def run(arguments):
 def download_icon_font(icon_font, directory):
     try:
         return AVAILABLE_ICON_FONTS[icon_font]['downloader'](directory)
-    except KeyError:
+    except KeyError:  # pragma: no cover
         raise Exception("We don't support downloading font '{name}'".format(
             name=icon_font)
         )

icon_font_to_png/icon_font_downloader.py

@@ -21,13 +21,11 @@ class IconFontDownloader(with_metaclass(ABCMeta)):
     @abstractmethod
     def css_url(self):
         """Icon font CSS file URL"""
-        pass
 
     @property
     @abstractmethod
     def ttf_url(self):
         """Icon font TTF file URL"""
-        pass
 
     def __init__(self, directory=None):
         """
@@ -64,7 +62,6 @@ def _get_latest_tag_from_github(repo_api_url):
     @abstractmethod
     def get_latest_version_number(self):
         """Get latest icon font version number"""
-        pass
 
     def download_css(self, directory):
         """Downloads icon font CSS file and returns its path"""

icon_font_to_png/test/test_command_line.py

@@ -47,6 +47,15 @@ def test_icon_export(capfd):
     css_file = os.path.join('files', 'font-awesome.css')
     ttf_file = os.path.join('files', 'fontawesome-webfont.ttf')
 
+    # Export none icons
+    with pytest.raises(SystemExit):
+        command_line.run(
+            '--css {css_file} --ttf {ttf_file}'.format(
+                css_file=css_file, ttf_file=ttf_file
+            ).split()
+        )
+    out, err = capfd.readouterr()  # For skipping stdout
+
     # Export one icon
     command_line.run(
         '--css {css_file} --ttf {ttf_file} github'.format(