[fktv] Raise an error is no videos found

youtube_dl/extractor/fktv.py

@@ -6,6 +6,7 @@ from .common import InfoExtractor
 from ..utils import (
     clean_html,
     determine_ext,
+    ExtractorError,
 )
 
 
@@ -29,10 +30,11 @@ class FKTVIE(InfoExtractor):
         webpage = self._download_webpage('http://fernsehkritik.tv/folge-%s/play' % episode, episode)
         title = clean_html(self._html_search_regex('<h3>([^<]+?)</h3>', webpage, 'title'))
         matches = re.search(r'(?s)<video[^>]*poster="([^"]+)"[^>]*>(.*?)</video>', webpage)
-        if matches:
+        if matches is None:
+            raise ExtractorError('Unable to extract the video')
+
         poster, sources = matches.groups()
         urls = re.findall(r'(?s)<source[^>]*src="([^"]+)"[^>]*>', sources)
-            if sources:
         formats = [{'url': url, 'format_id': determine_ext(url)} for url in urls]
         return {
             'id': episode,