added test of persistence of connector_words during save & load in te…

…st_phrases.py

gensim/test/test_phrases.py

@@ -95,7 +95,7 @@ class PhrasesData:
     sentences = common_texts + [
         ['graph', 'minors', 'survey', 'human', 'interface'],
     ]
-    connector_words = frozenset()
+    connector_words = frozenset({'of'})
 
     bigram1 = u'response_time'
     bigram2 = u'graph_minors'
@@ -321,9 +321,10 @@ def test_save_load_custom_scorer(self):
     def test_save_load(self):
         """Test saving and loading a Phrases object."""
         with temporary_file("test.pkl") as fpath:
-            bigram = Phrases(self.sentences, min_count=1, threshold=1)
+            bigram = Phrases(self.sentences, min_count=1, threshold=1, connector_words=self.connector_words)
             bigram.save(fpath)
             bigram_loaded = Phrases.load(fpath)
+            self.assertEqual(bigram_loaded.connector_words, frozenset(self.connector_words))
             test_sentences = [['graph', 'minors', 'survey', 'human', 'interface', 'system']]
             seen_scores = set(round(score, 3) for score in bigram_loaded.find_phrases(test_sentences).values())
 
@@ -378,9 +379,11 @@ def test_save_load_custom_scorer(self):
     def test_save_load(self):
         """Test saving and loading a FrozenPhrases object."""
         with temporary_file("test.pkl") as fpath:
-            bigram = FrozenPhrases(Phrases(self.sentences, min_count=1, threshold=1))
+            bigram = FrozenPhrases(
+                Phrases(self.sentences, min_count=1, threshold=1, connector_words=self.connector_words))
             bigram.save(fpath)
             bigram_loaded = FrozenPhrases.load(fpath)
+            self.assertEqual(bigram_loaded.connector_words, frozenset(self.connector_words))
             self.assertEqual(
                 bigram_loaded[['graph', 'minors', 'survey', 'human', 'interface', 'system']],
                 ['graph_minors', 'survey', 'human_interface', 'system'])