+        self.result.append(x)
+
+def get_testcases():
+    for ie in youtube_dl.extractor.gen_extractors():
+        t = getattr(ie, '_TEST', None)
+        if t:
+            t['name'] = type(ie).__name__[:-len('IE')]
+            yield t
+        for t in getattr(ie, '_TESTS', []):
+            t['name'] = type(ie).__name__[:-len('IE')]
+            yield t