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

"""
Tests for warning suppression features of Trial.
"""

from __future__ import division, absolute_import

import unittest as pyunit

from twisted.trial import unittest
from twisted.trial.test import suppression


class SuppressionMixin(object):
"""
Tests for the warning suppression features of
L{twisted.trial.unittest.SynchronousTestCase}.
"""
def runTests(self, suite):
suite.run(pyunit.TestResult())


def _load(self, cls, methodName):
"""
Return a new L{unittest.TestSuite} with a single test method in it.

@param cls: A L{TestCase} subclass defining a test method.

@param methodName: The name of the test method from C{cls}.
"""
return pyunit.TestSuite([cls(methodName)])


def _assertWarnings(self, warnings, which):
"""
Assert that a certain number of warnings with certain messages were
emitted in a certain order.

@param warnings: A list of emitted warnings, as returned by
C{flushWarnings}.

@param which: A list of strings giving warning messages that should
appear in C{warnings}.

@raise self.failureException: If the warning messages given by C{which}
do not match the messages in the warning information in C{warnings},
or if they do not appear in the same order.
"""
self.assertEqual(
[warning['message'] for warning in warnings],
which)


def test_setUpSuppression(self):
"""
Suppressions defined by the test method being run are applied to any
warnings emitted while running the C{setUp} fixture.
"""
self.runTests(
self._load(self.TestSetUpSuppression, "testSuppressMethod"))
warningsShown = self.flushWarnings([
self.TestSetUpSuppression._emit])
self._assertWarnings(
warningsShown,
[suppression.CLASS_WARNING_MSG, suppression.MODULE_WARNING_MSG,
suppression.CLASS_WARNING_MSG, suppression.MODULE_WARNING_MSG])


def test_tearDownSuppression(self):
"""
Suppressions defined by the test method being run are applied to any
warnings emitted while running the C{tearDown} fixture.
"""
self.runTests(
self._load(self.TestTearDownSuppression, "testSuppressMethod"))
warningsShown = self.flushWarnings([
self.TestTearDownSuppression._emit])
self._assertWarnings(
warningsShown,
[suppression.CLASS_WARNING_MSG, suppression.MODULE_WARNING_MSG,
suppression.CLASS_WARNING_MSG, suppression.MODULE_WARNING_MSG])


def test_suppressMethod(self):
"""
A suppression set on a test method prevents warnings emitted by that
test method which the suppression matches from being emitted.
"""
self.runTests(
self._load(self.TestSuppression, "testSuppressMethod"))
warningsShown = self.flushWarnings([
self.TestSuppression._emit])
self._assertWarnings(
warningsShown,
[suppression.CLASS_WARNING_MSG, suppression.MODULE_WARNING_MSG])


def test_suppressClass(self):
"""
A suppression set on a L{SynchronousTestCase} subclass prevents warnings
emitted by any test methods defined on that class which match the
suppression from being emitted.
"""
self.runTests(
self._load(self.TestSuppression, "testSuppressClass"))
warningsShown = self.flushWarnings([
self.TestSuppression._emit])
self.assertEqual(
warningsShown[0]['message'], suppression.METHOD_WARNING_MSG)
self.assertEqual(
warningsShown[1]['message'], suppression.MODULE_WARNING_MSG)
self.assertEqual(len(warningsShown), 2)


def test_suppressModule(self):
"""
A suppression set on a module prevents warnings emitted by any test
mewthods defined in that module which match the suppression from being
emitted.
"""
self.runTests(
self._load(self.TestSuppression2, "testSuppressModule"))
warningsShown = self.flushWarnings([
self.TestSuppression._emit])
self.assertEqual(
warningsShown[0]['message'], suppression.METHOD_WARNING_MSG)
self.assertEqual(
warningsShown[1]['message'], suppression.CLASS_WARNING_MSG)
self.assertEqual(len(warningsShown), 2)


def test_overrideSuppressClass(self):
"""
The suppression set on a test method completely overrides a suppression
with wider scope; if it does not match a warning emitted by that test
method, the warning is emitted, even if a wider suppression matches.
"""
self.runTests(
self._load(self.TestSuppression, "testOverrideSuppressClass"))
warningsShown = self.flushWarnings([
self.TestSuppression._emit])
self.assertEqual(
warningsShown[0]['message'], suppression.METHOD_WARNING_MSG)
self.assertEqual(
warningsShown[1]['message'], suppression.CLASS_WARNING_MSG)
self.assertEqual(
warningsShown[2]['message'], suppression.MODULE_WARNING_MSG)
self.assertEqual(len(warningsShown), 3)



class SynchronousSuppressionTest(SuppressionMixin, unittest.SynchronousTestCase):
"""
@see: L{twisted.trial.test.test_tests}
"""
from twisted.trial.test.suppression import (
SynchronousTestSetUpSuppression as TestSetUpSuppression,
SynchronousTestTearDownSuppression as TestTearDownSuppression,
SynchronousTestSuppression as TestSuppression,
SynchronousTestSuppression2 as TestSuppression2)