def testTrainWarning(self, loglines):
        """Test if warning is raised if alpha rises during subsequent calls to train()"""
        sentences = [
            ['human'],
            ['graph', 'trees']
        ]
        model = word2vec.Word2Vec(min_count=1)
        model.build_vocab(sentences)
        for epoch in range(10):
            model.train(sentences, total_examples=model.corpus_count, epochs=model.epochs)
            model.alpha -= 0.002
            model.min_alpha = model.alpha
            if epoch == 5:
                model.alpha += 0.05
        warning = "Effective 'alpha' higher than previous training cycles"
        self.assertTrue(warning in str(loglines))