Add validation for empty language code

Issue #153
Signed-off-by: Michal Čihař <michal@cihar.com>

weblate/trans/models/subproject.py

@@ -1039,6 +1039,10 @@ class SubProject(models.Model, PercentMixin, URLMixin, PathMixin):
         translated_langs = set()
         for match in matches:
             code = self.get_lang_code(match)
+            if not code:
+                raise ValidationError(_(
+                    'Got empty language code for %s, please check filemask!'
+                ) % match)
             lang = Language.objects.auto_get_or_create(code=code)
             if code in langs:
                 raise ValidationError(_(

weblate/trans/tests/test_models.py

@@ -689,6 +689,32 @@ class SubProjectTest(RepoTestCase):
             subproject.run_hook('true')
         )
 
+    def test_lang_code(self):
+        subproject = SubProject()
+        subproject.filemask = 'Solution/Project/Resources*.resx'
+        self.assertEqual(
+            subproject.get_lang_code('Solution/Project/Resources.es-mx.resx'),
+            '.es-mx'
+        )
+        self.assertEqual(
+            subproject.get_lang_code('Solution/Project/Resources.resx'),
+            ''
+        )
+        self.assertRaisesMessage(
+            ValidationError,
+            'Got empty language code for '
+            'Solution/Project/Resources.resx, please check filemask!',
+            subproject.clean_lang_codes,
+            [
+                'Solution/Project/Resources.resx',
+                'Solution/Project/Resources.de.resx',
+                'Solution/Project/Resources.es.resx',
+                'Solution/Project/Resources.es-mx.resx',
+                'Solution/Project/Resources.fr.resx',
+                'Solution/Project/Resources.fr-fr.resx',
+            ]
+        )
+
 
 class TranslationTest(RepoTestCase):
     """