Enhance detection of a theme directory.

sigal/settings.py

@@ -132,7 +132,9 @@ def read_settings(filename=None):
         # Make the paths relative to the settings file
         paths = ['source', 'destination', 'watermark']
 
-        if os.path.isdir(join(settings_path, settings['theme'])):
+        if os.path.isdir(join(settings_path, settings['theme'])) and \
+                os.path.isdir(join(settings_path, settings['theme'],
+                                   'templates')):
             paths.append('theme')
 
         enc = locale.getpreferredencoding() if PY2 else None

sigal/writer.py

@@ -53,7 +53,8 @@ class Writer(object):
         self.logger = logging.getLogger(__name__)
 
         # search the theme in sigal/theme if the given one does not exists
-        if not os.path.exists(self.theme):
+        if not os.path.exists(self.theme) or \
+                not os.path.exists(os.path.join(self.theme, 'templates')):
             self.theme = os.path.join(THEMES_PATH, self.theme)
             if not os.path.exists(self.theme):
                 raise Exception("Impossible to find the theme %s" % self.theme)

tests/test_settings.py

@@ -48,6 +48,7 @@ def test_theme_path(tmpdir):
     """Test that image size is swaped if needed."""
 
     tmpdir.join('theme').mkdir()
+    tmpdir.join('theme').join('templates').mkdir()
     conf = tmpdir.join('sigal.conf.py')
     conf.write("""# -*- coding: utf-8 -*-