test: [WFE] Negative and aprtial tests

Ensure:
 - no words are correctly not matched
 - some words are matched

test/test_feature_extractors.py

@@ -337,8 +337,8 @@ class TestWordFeatureExtractor(unittest.TestCase):
         test_extractor.teardown()
         self.assertEqual(test_extractor.features, [])
 
-    def test_extract_mocked_transcribe(self):
-        """Mock out the actual call to transcribe"""
+    def test_extract_mocked_transcribe_matching_words(self):
+        """Mock out the actual call to transcribe but match all words in the sentence"""
         video_source = TestSourceMedia().one_colour_silent_audio()
         test_extractor = extractors.WordFeatureExtractor(input_files=video_source)
         # mock _transcribe and mock out model and batched pipeline for speed
@@ -352,3 +352,33 @@ class TestWordFeatureExtractor(unittest.TestCase):
 
         self.assertEqual(len(test_extractor.features), 9)
 
+    def test_extract_mocked_transcribe_no_matching_words(self):
+        """Mock out the actual call to transcribe but match no words in the sentence"""
+        video_source = TestSourceMedia().one_colour_silent_audio()
+        test_extractor = extractors.WordFeatureExtractor(input_files=video_source)
+        # mock _transcribe and mock out model and batched pipeline for speed
+        test_extractor._transcribe = self.mock_transcribe
+        test_extractor._model = MagicMock()
+        test_extractor._batched_model = MagicMock()
+        # set up and run the extractor
+        test_extractor.setup(words=["nonexistentword"])
+        test_extractor.run()
+        test_extractor.teardown()
+
+        self.assertEqual(len(test_extractor.features), 0)
+
+
+    def test_extract_mocked_transcribe_some_matching_words(self):
+        """Mock out the actual call to transcribe but match some words in the sentence"""
+        video_source = TestSourceMedia().one_colour_silent_audio()
+        test_extractor = extractors.WordFeatureExtractor(input_files=video_source)
+        # mock _transcribe and mock out model and batched pipeline for speed
+        test_extractor._transcribe = self.mock_transcribe
+        test_extractor._model = MagicMock()
+        test_extractor._batched_model = MagicMock()
+        # set up and run the extractor
+        test_extractor.setup(words=["quick", "jumps", "dog"])
+        test_extractor.run()
+        test_extractor.teardown()
+
+        self.assertEqual(len(test_extractor.features), 3)