Old Test System

Mycroft has a built-in mechanism to help you automatically test your Skill. This is particularly important when submitting your Skill for inclusion in the Marketplace.

Automatic testing of Skills helps increase the quality of the Mycroft ecosystem overall, and helps assure you that your Skill is performing as intended. Tests are required to be passing before your Skill will be accepted into the Mycroft Skill repository on GitHub.


The Integration Test Runner tests Mycroft Skills by emulating Utterances expected to be spoken by the User, sending them to the Skill, and then checking to see if the Skill responds as expected.

The Integration Test Runner can test:

  • That the expected Intent in the Skill is activated

  • That the expected parameters are extracted from the Utterance

  • That Mycroft contexts are set or removed

  • That the Skill speaks the intended dialog

  • The content of any message exchanged between the Skill and Mycroft Core

To initialize a test, the Integration Test Runner can:

  • Send an Utterance - that is, a phrase the User would normally speak

  • Set up and remove context

  • Set up a custom timeout for the Integration Test Runner, to allow for Skills that run for a very long time

NOTE: If you have submitted your Skill to the mycroft-skills repo and wish to run tests to ensure they are still passing, you can add the comment Run test to the PR and this will automatically initiate a Jenkins CI runthrough of the tests in the Skill.

The Integration Test Runner files

The Integration Test Runner is part of the mycroft-core package. It consists of the following files in mycroft-core/test/integrationtests/skills:

  • discover_tests.py

  • skill_tester.py

  • runner.py

  • message_tester.py

  • test_all_skills.py

The most interesting files from a Skill Author's perspective are:

The runner.py can be copied to the Skill Author's working directory, where the Skill's __init__.py file exists or invoked directly with the skill path as argument. Running runner.py will test only the Skills it finds in the directory it is in, or, if it can’t find a Skill, it will search any subdirectory.

The discover_test.py is the Python file that runs integration tests on all Skills in /opt/mycroft/skills. It is intended for debugging that all your tests are found by the test runner.

The message_tester.py is a utility that can test a single message against the internal rule format used by the skill_tester. It is intended for debugging rules.

The test_all_skills.py tests all Skills at the Skill level, where discover_tests.py tests at the Intent level. Because of that, test_all_skills.py not only runs all the Intent tests, it also determines if all Intents in a Skill are tested, i.e. if any test cases are missing. It prints a list of missing test cases for each Skill, and fails if it finds any.

How to define tests for your Skill

A Skill can define a test suite consisting of a number of files (test cases), which are placed in the Skill's test/intent directory. Each test case corresponds to one Utterance. All parts of the test case are optional, except the Utterance. The test case files are executed by the Integration Test Runner, one after another, and they are executed in alphabetical order. Alphabetic ordering can be used for compensating (trans)actions, for instance first add to a list, then remove from a list, to leave the list unchanged.

The test case files in the test/intent directory are written in JSON format, and must be named to match the pattern *.intent.json

An example test suite might look like this:

ls test/intent

A test case file understands the following JSON keywords:




The text to send to the skill, like it was a spoken command


Assert that this intent name, as defined in the skills __init__.py code, is used


Assert that a message parameter has a certain value. Repeating field.


Assert that a message is sent with the expected data. Takes a sub dictionary as argument


Assert that the skill responds with a response from a certain dialog file


Assert that the skill speaks a response that matches this regular expression


A list of strings to send as follow up responses if prompted


The default timeout is 30 seconds. If a skill takes longer than this to finish, the evaluation_timeout can be set


A list of contexts and corresponding strings to set before sending the utterance


A list of contexts to remove before sending the utterance


Assert that a list of contexts was set or removed


Assert that a rule, expressed in the internal test runner format, is true


Provides a custom temporary settings structure for the test, replacing the normal settings.json.

Here is a simple example based on the Timer Skill:

  "utterance": "start a timer",
  "intent_type": "start.timer.intent",
  "expected_dialog": "ask.how.long",
  "responses": ["1 minute"],
  "expected_dialog": "started.timer"

Or we can get more complicated:

  "utterance": "add milk to the grocery list",
  "remove_context": ["UndoContext", "ConfirmContext"],
  "set_context": {"_TestRunner": "data", "test": ""},
  "intent_type": "AddTaskToListIntent",
  "intent": {
    "taskName": "milk",
    "listName": "grocery",
    "AddTaskToListKeyword": "add"
  "expected_response": "I can't find a list called grocery.*",
  "evaluation_timeout": 10,
  "changed_context": ["UndoContext", "ConfirmContext"],
  "assert": "[['equal', 'context', 'UndoContext'], ['equal', 'context', 'ConfirmContext']]"

In the example above, some of the things asserted are not really needed, they are only provided to create an example demonstrating all possibilities.

A snippet of the Intent to be tested looks like this:

def add_task_to_list_intent(self, message):
    if message.data.get('_TestRunner'):
    print("Initiated by the test runner")

And the message regular expression from the regex/en-us directory is: add (?P.+) to (?P.+) list$

The AddTaskToListKeyword is Add, defined in the vocab/en-us directory.

With this knowledge, let us walk through the test case.

The test case to simulate the user Utterance:

add milk to the grocery list

Assuming other tests were run before this example, the UndoContext and the ConfirmContext may have been set, but to be sure they are removed, we remove them before the test starts.

The set_context can be used to test Intents that require a context. In the example above the _TestRunner context is set to "data". When the Skill has side effects that are unwanted when testing, this trick allows us to test for the _TestRunner context in the Intent, and behave accordingly, for instance not executing code with side effects. Of course, other tests are then required to test the inner working of the Intent.

The intent_type is used to verify that the Utterance is passed to the right Intent, hence it must the IntentBuilder() parameter. In this case AddTaskToListIntent.

The intent is a list of key/values that must match the IntentBuilder().require() or similar parameters. This is used for testing that the right part of the Utterance is passed as parameters to the Skill.

The expected response is a regular expression that must match the answer that is Spoken by the Intent.

The changed_context is a list of contexts, that the Intent has set or removed. It is not possible to distinguish between set or remove context.

The expected_data can be used to check for specific data content, for example the content of a message parsed with Padatious. The example test case below will pass if a message contains an "ampm" value equal to "pm" and a "time" value equal to 6. Note that the "ampm" value is a string literal, and is quoted, while the "time" value is an integer value and is not quoted.

  "expected_data": {
    "ampm": "pm",
    "time": 6

Note that the message can contain additional fields without the test failing.

The expected_dialog takes the dialog file (without the .dialog) in the same manner as when using the dialog in the Skill. See skill-personal for an example.

In the example above the changed_context and assert actually does the same thing, it is mentioned as an example only. The assert shows the internal rule format (see the next paragraph).

A test case succeeds if all tests are passed for the Intent. And in that case the Integration Test Runner immediately continues to the next test. If all tests have not succeeded 30 seconds after the Utterance, the test is failed. In the example above the timeout is reduced to 10 seconds to catch errors faster.

The internal rule format

If the standard keywords in the test case file does not suffice, it is possible to write tests in the internal rule format, using the assert keyword. The standard keywords and values are translated into the internal rule format by the Integration Test Runner as well.

The example test case above is actually transformed into:

    ['endsWith', 'intent_type', 'AddTaskToListIntent'], ['equal', 'listName', 'none'],
    ['equal', 'taskName', 'some'],
    ['equal', 'AddTaskToListKeyword', 'add']
  ['match', 'utterance', "I can't find a list called none.*"],
  ['equal', 'context', 'UndoContext'],
  ['equal', 'context', 'ConfirmContext'],
  ['equal', 'context', 'UndoContext'],
  ['equal', 'context', 'ConfirmContext']

The double test of contexts in the end is due to both using changed_context and assert, one of which is of course not needed.

The internal test format above is actually quite powerful. The code already supports that operations can be nested to any depth, for instance:

    ['endsWith', 'type', 'AddTaskToListIntent'],
    ['equal', ['data', 'listName'], 'none'],
    ['equal', ['data', 'taskName'], 'some']
    ['equal', ['data', 'AddTaskToListKeyword'], 'add']

and besides "and" also "or" and "not" are supported. Likewise the operations “equal”, “notEqual”, “endsWith” and “match” are supported, where match is regular expression matching.

Handling Skills with side effects

As mentioned in the example above, context can be used to make an Intent aware that it is the Integration Test Runner that is initiating the call. With this knowledge unwanted side effects can be avoided.

Executing the Integration Test Runner

The discover_tests.py is intended to be run like a Python unit test, please refer to https://docs.python.org/2/library/unittest.html. Most IDEs have an easy way to run unit tests, and create nice structured test reports.

The runner.py is intended to run with a skill directory as parameter,

ake@Woodstock:~/projects/python/mycroft-core$ source venv-activate.sh
ake@Woodstock:~/projects/python/mycroft-core$ python -m test.integrationtests.skills.runner PATH/TO/SKILL

or directly in the Skill directory:

ake@Woodstock:~/projects/python/mycroft-core$ source venv-activate.sh
ake@Woodstock:~/projects/python/mycroft-core$ cd /PATH/TO/SKILL
ake@Woodstock:/PATH/TO/SKILL$ python -m test.integrationtests.skills.runner

When run, it will search the directory it is in, and subdirectories, until it finds an __init__.py file. When it does, it will not traverse further down from that directory, but it will search sibling directories. In effect, it will only test one Skill, if it is run in that Skill's directory. runner.py is an excellent tool when developing a Skill and wanting to run only the tests for that Skill.

Troubleshooting tests

Each message event is tested by the rules. When all rules have succeeded, the test ends. When a rule succeeds, the string ”Succeeded” is appended to the rule (see the "Rule status" in the test case output file below). During execution, the test runner prints the messages received from the Skill. An example test run is shown below (some output has been left out to keep the example short):

Test case output file:

Test case: {u'intent': {u'DevicePairingPhrase': u'pair my device'}, u'intent_type': u'PairingIntent', u'utterance': u"let's pair my device"}
Rule created [['and', ['endsWith', 'intent_type', 'PairingIntent'], ['equal', 'DevicePairingPhrase', 'pair my device']]]
Evaluating message: {'lang': 'en-us', 'skill_id': 1211234571, 'utterances': [u"let's pair my device"]}
Evaluating message: {'confidence': 1.0, 'target': None, 'DeviceKeyword': 'device', 'intent_type': '1211234573:PairingIntent', 'PairingKeyword': 'pair', '__tags__': [{'end_token': 2, 'start_token': 2, 'from_context': False, 'entities': [{'confidence': 1.0, 'data': [('pair', u'BCBBCDEFHDPairingKeyword')], 'match': u'pair', 'key': 'pair'}], 'key': 'pair', 'match': u'pair'}, {'end_token': 4, 'start_token': 4, 'from_context': False, 'entities': [{'confidence': 1.0, 'data': [('device', u'BCBBCDEFHDDeviceKeyword')], 'match': u'device', 'key': 'device'}], 'key': 'device', 'match': u'device'}], 'utterance': u"let's pair my device"}
Evaluating message: {'name': 'PairingSkill.handle_pairing'}
Evaluating message: {'expect_response': False, 'utterance': u'Now I am ready for use. Try asking me things like "hey mycroft, what's the weather", "hey mycroft, tell me about abraham lincoln", or "hey mycroft, play the news". If you need to stop me talking at any time, just push my button.'}
Evaluating message: {'name': 'PairingSkill.handle_pairing'}
Evaluation failed
Rule status: [['and', ['endsWith', 'intent_type', 'PairingIntent', 'succeeded'], ['equal', 'DevicePairingPhrase', 'pair my device']]]

Traceback (most recent call last):

In the first line the test case is printed, in the second line the rules created from the test case are printed. Then comes a number of “Evaluating message” lines, that each represent a message event. Near the end we find the “Rule status” which shows what rules succeeded.

In the rule status we find ['endsWith', 'intent_type', 'PairingIntent', 'succeeded'] which means that the Intent type was found, since “succeeded” was appended to that rule part. However, we did not find the DevicePairingPhrase in the same message. We expect the DevicePairingPhrase in the same message because of the “and” operator. And if we look at the messages in the log above, we can’t find a message where the DevicePairingPhrase appear.

To see this more clearly, it sometimes pays off to reformat the rule status:

    ['endsWith', 'intent_type', 'PairingIntent', 'succeeded'],
    ['equal', 'DevicePairingPhrase', 'pair my device']

The message_tester.py tool is able to evaluate one message event at a time, for instance:

Not surprisingly it yields the same result as the Integration Test Runner.

Example of a failing test

This is an example of a failing test where the Skill can't be found:

self =
loader =
def run(self, loader):
Run a test for a skill. The skill, test_case_file and emitter is
already set up in the __init__ method

loader: A list of loaded skills

s = [s for s in loader.skills if s and s._dir == self.skill]
if s:
s = s[0]
> raise Exception('Skill couldn't be loaded')
E Exception: Skill couldn't be loaded
test/integrationtests/skills/skill_tester.py:198: Exception
self =
skill = '/opt/mycroft/skills/skill-alarm'
example = '/opt/mycroft/skills/skill-alarm/test/intent/sample7.intent.json'
@pytest.mark.parametrize("skill,example", sum([
[(skill, example) for example in tests[skill]]
for skill in tests.keys()
], []))
def test_skill(self, skill, example):

Test coverage

The last section of the Integration Test Runner output shows the test coverage - how many lines of code are covered by the tests. In general, the more coverage of a Skill, the better.

---------- coverage: platform linux2, python 2.7.12-final-0 ----------
Name Stmts Miss Cover
/opt/mycroft/skills/skill-alarm/__init__.py 293 290 1%

What should I do if the tests that are failing are not within my control?

If you are running the automated tests, and have test failures that are beyond your control - for example the error is triggered by something in mycroft-core or other Mycroft software, then the Skills Management Team can choose to override the need for automated tests to have passed when they assess the Skill.

Please paste a copy of the automated Skill testing output as a comment in the Pull Request when you submit it to the Skills repo.

Where can I go to get more assistance?

Join us in the ~skills channel in Mycroft Chat.

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