set active lang to configured if missing from STT and normalize

[forslund]

Description

I ran across this when checking some questions I had surrounding mycroft-timer PR #77

If the STT doesn't send a lang code fallback to configured language instead of hardcoded en-us. This should at least be more correct than the previous behaviour.

How to test

Check that Mycroft operates as usual and that the new unittest passes

Contributor license agreement signed?

CLA [ Yes ]

[devops-mycroft]

Voight Kampff Integration Test Succeeded (Results)

[devops-mycroft]

Voight Kampff Integration Test Succeeded (Results)

[krisgesling]

Nice!

Is there going to be a benefit in re-using this elsewhere? ie should this be an imported util?

In terms of testing, is it worth us adding a test for a globally configured lang code?
Something like:

    def test_config_lang(self):
        msg = Message('test msg', data={})
        config = {'lang': 'it-it'}
        Configuration.patch(Message('patch', data={'config': config}))
        self.assertEqual(_get_message_lang(msg), 'it-it')
        Configuration.patch_clear(msg)

Sidenote - It seems like patch_clear doesn't really need any arguments, the Message arg looks like it's just been copy-pasted from the patch method. Will do a PR to propose removing that.

[krisgesling]

disregard the patch_clear sidenote, just saw that it's got a messagebus handler so the Message arg makes total sense.

[forslund]

I've added an explicit testcase for the case when the config doesn't contain a language code and changed it so the configured language code in the test is 'it-it' which should indeed be better than using the 'en-us' one which would be invisible.

I don't think it's of much use outside of the intentservice, the function could technically be placed in mycroft.util.lang, but since this is marked as "private" with the underscore, placing it here for now should be fine. If another use is found it can be added there and this can be removed.

[devops-mycroft]

Voight Kampff Integration Test Succeeded (Results)