recipe_modules/assertions/tests/assert-raises.py

# Copyright 2019 The LUCI Authors. All rights reserved.
# Use of this source code is governed under the Apache License, Version 2.0
# that can be found in the LICENSE file.

from recipe_engine import post_process

DEPS = [
    'assertions',
    'properties',
    'step',
]

class TestException(Exception):
  pass

def RunSteps(api):
  try:
    with api.assertions.assertRaises(TestException) as caught:
      exception_message = api.properties.get('exception_message', '')
      if exception_message:
        raise TestException(exception_message)
  except AssertionError:
    api.step('AssertionError', [])
  else:
    api.step('No AssertionError', [])
    assert caught.exception.message == exception_message, (
        'Context manager not working, '
        'expected TestException with message: %r\n actual message %r'
        % (exception_message, caught.exception.message))

def GenTests(api):
  yield (
      api.test('no-exception')
      + api.post_process(post_process.MustRun, 'AssertionError')
      + api.post_process(post_process.DropExpectation)
  )

  yield (
      api.test('exception')
      + api.properties(exception_message='fake exception message')
      + api.post_process(post_process.MustRun, 'No AssertionError')
      + api.post_process(post_process.DropExpectation)
  )