# Copyright (c) Twisted Matrix Laboratories.
# See LICENSE for details.

"""
Tests for async assertions provided by C{twisted.trial.unittest.TestCase}.
"""

from __future__ import division, absolute_import

import unittest as pyunit

from twisted.python import failure
from twisted.internet import defer
from twisted.trial import unittest


class TestAsynchronousAssertions(unittest.TestCase):
"""
Tests for L{TestCase}'s asynchronous extensions to L{SynchronousTestCase}.
That is, assertFailure.
"""
def test_assertFailure(self):
d = defer.maybeDeferred(lambda: 1/0)
return self.assertFailure(d, ZeroDivisionError)


def test_assertFailure_wrongException(self):
d = defer.maybeDeferred(lambda: 1/0)
self.assertFailure(d, OverflowError)
d.addCallbacks(lambda x: self.fail('Should have failed'),
lambda x: x.trap(self.failureException))
return d


def test_assertFailure_noException(self):
d = defer.succeed(None)
self.assertFailure(d, ZeroDivisionError)
d.addCallbacks(lambda x: self.fail('Should have failed'),
lambda x: x.trap(self.failureException))
return d


def test_assertFailure_moreInfo(self):
"""
In the case of assertFailure failing, check that we get lots of
information about the exception that was raised.
"""
try:
1/0
except ZeroDivisionError:
f = failure.Failure()
d = defer.fail(f)
d = self.assertFailure(d, RuntimeError)
d.addErrback(self._checkInfo, f)
return d


def _checkInfo(self, assertionFailure, f):
assert assertionFailure.check(self.failureException)
output = assertionFailure.getErrorMessage()
self.assertIn(f.getErrorMessage(), output)
self.assertIn(f.getBriefTraceback(), output)


def test_assertFailure_masked(self):
"""
A single wrong assertFailure should fail the whole test.
"""
class ExampleFailure(Exception):
pass

class TC(unittest.TestCase):
failureException = ExampleFailure
def test_assertFailure(self):
d = defer.maybeDeferred(lambda: 1/0)
self.assertFailure(d, OverflowError)
self.assertFailure(d, ZeroDivisionError)
return d

test = TC('test_assertFailure')
result = pyunit.TestResult()
test.run(result)
self.assertEqual(1, len(result.failures))