phlax / aio.testing

aio.testing

Test utils for the aio asyncio framework

Build status

Installation

Requires python >= 3.4

Install with:

pip install aio.testing

Aio testing provides 2 decorators for running asyncio tests

• aio.testing.run_until_complete:
  • creates a test loop
  • calls the test with loop.run_until_complete
• aio.testing.run_forever:
  • creates a test loop
  • calls test using loop.run_forever
  • waits for number of seconds specified in "timeout" (default = 1)
  • if test returns a callable, calls it as a coroutine
  • waits for number of seconds specified in "sleep" (default = 0)

@aio.testing.run_until_complete

aio.testing provides a method decorator for running asyncio-based tests

import unittest
import asyncio

import aio.testing


class MyTestCase(unittest.TestCase):

    @aio.testing.run_until_complete
    def test_example():
        yield from asyncio.sleep(2)
        self.assertTrue(True)

Prior to the test running asyncio.get_new_loop() is called and set using asyncio.set_event_loop().

On completion of the test asyncio.set_event_loop() is again called with the original event loop.

@aio.testing.run_forever

If your code needs to test long-running tasks, you can use the @aio.testing.run_forever decorator.

The @aio.testing.run_forever decorator uses loop.run_forever to run the test.

Any setup required can be done in the body of the test function which can optionally return a test callback

The callback is wrapped in a coroutine, and called after 1 second

import unittest
import asyncio

import aio.testing


class MyFutureTestCase(unittest.TestCase):

    @aio.testing.run_forever
    def test_example():
        yield from asyncio.sleep(2)

        def callback_test(self):
            yield from asyncio.sleep(2)
            self.assertTrue(True)

        # this function is called 1 second after being returned
        return callback_test

As with aio.testing.run_until_complete, the test is run in a separate loop.

@aio.testing.run_forever with timeout

You can specify how many seconds to wait before running the callback tests by setting the timeout value

import unittest
import asyncio

import aio.testing


class MyFutureTestCase(unittest.TestCase):

    @aio.testing.run_forever(timeout=10)
    def test_example():
        yield from asyncio.sleep(2)

        def callback_test(self):
            yield from asyncio.sleep(2)
            self.assertTrue(True)

        # this function is called 10 seconds after being returned
        return callback_test

@aio.testing.run_forever with sleep

Sometimes a test needs to wait for some time after services have been stopped and the test loop has been destroyed.

You can specify how many seconds to wait after running the callback tests by setting the sleep value

import unittest
import asyncio

import aio.testing


class MyFutureTestCase(unittest.TestCase):

    @aio.testing.run_forever(sleep=10)
    def test_example():
        yield from asyncio.sleep(2)

        def callback_test(self):
            yield from asyncio.sleep(2)
            self.assertTrue(True)

        return callback_test

Supplying your own event loop

By default, aio.testing creates a new event loop for each test. There may be times that you prefer to control which event loop the tests are executed on. For example, you may create some expensive resource on a loop in a fixture that you wish to share among tests.

Both aio.testing.run_until_complete and aio.testing.run_forever accept an optional named argument called loop. The value of loop should be a context manager that returns a loop. aio.testing provides the current_loop context manager which simply returns the value of asyncio.get_event_loop():

import unittest
import asyncio

import aio.testing


class MyTestCase(unittest.TestCase):

    @classmethod
    def setUpClass(cls):
        cls.loop = asyncio.get_event_loop()

    @aio.testing.run_until_complete(loop=aio.testing.current_loop)
    def test_example():
        yield from asyncio.sleep(2)
        self.assertEqual(asyncio.get_event_loop(), MyTestCase.loop)

Contributing

To run unit tests, use:

python setup.py test

To run doc tests, use:

python -m doctest aio/testing/README.rst