cpython/Lib/test/test_warnings.py
Brett Cannon e974689038 Re-implement the 'warnings' module in C. This allows for usage of the
'warnings' code in places where it was previously not possible (e.g., the
parser). It could also potentially lead to a speed-up in interpreter start-up
if the C version of the code (_warnings) is imported over the use of the
Python version in key places.

Closes issue #1631171.
2008-04-12 23:44:07 +00:00

391 lines
15 KiB
Python

from contextlib import contextmanager
import linecache
import os
import StringIO
import sys
import unittest
from test import test_support
import warning_tests
sys.modules['_warnings'] = 0
if 'warnings' in sys.modules:
del sys.modules['warnings']
import warnings as py_warnings
del sys.modules['_warnings']
del sys.modules['warnings']
import warnings as c_warnings
@contextmanager
def warnings_state(module):
"""Use a specific warnings implementation in warning_tests."""
global __warningregistry__
for to_clear in (sys, warning_tests):
try:
to_clear.__warningregistry__.clear()
except AttributeError:
pass
try:
__warningregistry__.clear()
except NameError:
pass
original_warnings = warning_tests.warnings
try:
warning_tests.warnings = module
yield
finally:
warning_tests.warnings = original_warnings
class FilterTests(unittest.TestCase):
"""Testing the filtering functionality."""
def setUp(self):
global __warningregistry__
try:
__warningregistry__.clear()
except NameError:
pass
def test_error(self):
with test_support.catch_warning(self.module) as w:
self.module.resetwarnings()
self.module.filterwarnings("error", category=UserWarning)
self.assertRaises(UserWarning, self.module.warn,
"FilterTests.test_error")
def test_ignore(self):
with test_support.catch_warning(self.module) as w:
self.module.resetwarnings()
self.module.filterwarnings("ignore", category=UserWarning)
self.module.warn("FilterTests.test_ignore", UserWarning)
self.assert_(not w.message)
def test_always(self):
with test_support.catch_warning(self.module) as w:
self.module.resetwarnings()
self.module.filterwarnings("always", category=UserWarning)
message = "FilterTests.test_always"
self.module.warn(message, UserWarning)
self.assert_(message, w.message)
w.message = None # Reset.
self.module.warn(message, UserWarning)
self.assert_(w.message, message)
def test_default(self):
with test_support.catch_warning(self.module) as w:
self.module.resetwarnings()
self.module.filterwarnings("default", category=UserWarning)
message = UserWarning("FilterTests.test_default")
for x in xrange(2):
self.module.warn(message, UserWarning)
if x == 0:
self.assertEquals(w.message, message)
w.reset()
elif x == 1:
self.assert_(not w.message, "unexpected warning: " + str(w))
else:
raise ValueError("loop variant unhandled")
def test_module(self):
with test_support.catch_warning(self.module) as w:
self.module.resetwarnings()
self.module.filterwarnings("module", category=UserWarning)
message = UserWarning("FilterTests.test_module")
self.module.warn(message, UserWarning)
self.assertEquals(w.message, message)
w.reset()
self.module.warn(message, UserWarning)
self.assert_(not w.message, "unexpected message: " + str(w))
def test_once(self):
with test_support.catch_warning(self.module) as w:
self.module.resetwarnings()
self.module.filterwarnings("once", category=UserWarning)
message = UserWarning("FilterTests.test_once")
self.module.warn_explicit(message, UserWarning, "test_warnings.py",
42)
self.assertEquals(w.message, message)
w.reset()
self.module.warn_explicit(message, UserWarning, "test_warnings.py",
13)
self.assert_(not w.message)
self.module.warn_explicit(message, UserWarning, "test_warnings2.py",
42)
self.assert_(not w.message)
def test_inheritance(self):
with test_support.catch_warning(self.module) as w:
self.module.resetwarnings()
self.module.filterwarnings("error", category=Warning)
self.assertRaises(UserWarning, self.module.warn,
"FilterTests.test_inheritance", UserWarning)
def test_ordering(self):
with test_support.catch_warning(self.module) as w:
self.module.resetwarnings()
self.module.filterwarnings("ignore", category=UserWarning)
self.module.filterwarnings("error", category=UserWarning,
append=True)
w.reset()
try:
self.module.warn("FilterTests.test_ordering", UserWarning)
except UserWarning:
self.fail("order handling for actions failed")
self.assert_(not w.message)
def test_filterwarnings(self):
# Test filterwarnings().
# Implicitly also tests resetwarnings().
with test_support.catch_warning(self.module) as w:
self.module.filterwarnings("error", "", Warning, "", 0)
self.assertRaises(UserWarning, self.module.warn, 'convert to error')
self.module.resetwarnings()
text = 'handle normally'
self.module.warn(text)
self.assertEqual(str(w.message), text)
self.assert_(w.category is UserWarning)
self.module.filterwarnings("ignore", "", Warning, "", 0)
text = 'filtered out'
self.module.warn(text)
self.assertNotEqual(str(w.message), text)
self.module.resetwarnings()
self.module.filterwarnings("error", "hex*", Warning, "", 0)
self.assertRaises(UserWarning, self.module.warn, 'hex/oct')
text = 'nonmatching text'
self.module.warn(text)
self.assertEqual(str(w.message), text)
self.assert_(w.category is UserWarning)
class CFilterTests(FilterTests):
module = c_warnings
class PyFilterTests(FilterTests):
module = py_warnings
class WarnTests(unittest.TestCase):
"""Test warnings.warn() and warnings.warn_explicit()."""
def test_message(self):
with test_support.catch_warning(self.module) as w:
for i in range(4):
text = 'multi %d' %i # Different text on each call.
self.module.warn(text)
self.assertEqual(str(w.message), text)
self.assert_(w.category is UserWarning)
def test_filename(self):
with warnings_state(self.module):
with test_support.catch_warning(self.module) as w:
warning_tests.inner("spam1")
self.assertEqual(os.path.basename(w.filename), "warning_tests.py")
warning_tests.outer("spam2")
self.assertEqual(os.path.basename(w.filename), "warning_tests.py")
def test_stacklevel(self):
# Test stacklevel argument
# make sure all messages are different, so the warning won't be skipped
with warnings_state(self.module):
with test_support.catch_warning(self.module) as w:
warning_tests.inner("spam3", stacklevel=1)
self.assertEqual(os.path.basename(w.filename), "warning_tests.py")
warning_tests.outer("spam4", stacklevel=1)
self.assertEqual(os.path.basename(w.filename), "warning_tests.py")
warning_tests.inner("spam5", stacklevel=2)
self.assertEqual(os.path.basename(w.filename), "test_warnings.py")
warning_tests.outer("spam6", stacklevel=2)
self.assertEqual(os.path.basename(w.filename), "warning_tests.py")
warning_tests.inner("spam7", stacklevel=9999)
self.assertEqual(os.path.basename(w.filename), "sys")
class CWarnTests(WarnTests):
module = c_warnings
class PyWarnTests(WarnTests):
module = py_warnings
class WCmdLineTests(unittest.TestCase):
def test_improper_input(self):
# Uses the private _setoption() function to test the parsing
# of command-line warning arguments
with test_support.catch_warning(self.module):
self.assertRaises(self.module._OptionError,
self.module._setoption, '1:2:3:4:5:6')
self.assertRaises(self.module._OptionError,
self.module._setoption, 'bogus::Warning')
self.assertRaises(self.module._OptionError,
self.module._setoption, 'ignore:2::4:-5')
self.module._setoption('error::Warning::0')
self.assertRaises(UserWarning, self.module.warn, 'convert to error')
class CWCmdLineTests(WCmdLineTests):
module = c_warnings
class PyWCmdLineTests(WCmdLineTests):
module = py_warnings
class _WarningsTests(unittest.TestCase):
"""Tests specific to the _warnings module."""
module = c_warnings
def test_filter(self):
# Everything should function even if 'filters' is not in warnings.
with test_support.catch_warning(self.module) as w:
self.module.filterwarnings("error", "", Warning, "", 0)
self.assertRaises(UserWarning, self.module.warn,
'convert to error')
del self.module.filters
self.assertRaises(UserWarning, self.module.warn,
'convert to error')
def test_onceregistry(self):
# Replacing or removing the onceregistry should be okay.
global __warningregistry__
message = UserWarning('onceregistry test')
try:
original_registry = self.module.onceregistry
__warningregistry__ = {}
with test_support.catch_warning(self.module) as w:
self.module.resetwarnings()
self.module.filterwarnings("once", category=UserWarning)
self.module.warn_explicit(message, UserWarning, "file", 42)
self.failUnlessEqual(w.message, message)
w.reset()
self.module.warn_explicit(message, UserWarning, "file", 42)
self.assert_(not w.message)
# Test the resetting of onceregistry.
self.module.onceregistry = {}
__warningregistry__ = {}
self.module.warn('onceregistry test')
self.failUnlessEqual(w.message.args, message.args)
# Removal of onceregistry is okay.
w.reset()
del self.module.onceregistry
__warningregistry__ = {}
self.module.warn_explicit(message, UserWarning, "file", 42)
self.failUnless(not w.message)
finally:
self.module.onceregistry = original_registry
def test_showwarning_missing(self):
# Test that showwarning() missing is okay.
text = 'del showwarning test'
with test_support.catch_warning(self.module):
self.module.filterwarnings("always", category=UserWarning)
del self.module.showwarning
with test_support.captured_output('stderr') as stream:
self.module.warn(text)
result = stream.getvalue()
self.failUnless(text in result)
def test_show_warning_output(self):
# With showarning() missing, make sure that output is okay.
text = 'test show_warning'
with test_support.catch_warning(self.module):
self.module.filterwarnings("always", category=UserWarning)
del self.module.showwarning
with test_support.captured_output('stderr') as stream:
warning_tests.inner(text)
result = stream.getvalue()
self.failUnlessEqual(result.count('\n'), 2,
"Too many newlines in %r" % result)
first_line, second_line = result.split('\n', 1)
expected_file = os.path.splitext(warning_tests.__file__)[0] + '.py'
path, line, warning_class, message = first_line.split(':')
line = int(line)
self.failUnlessEqual(expected_file, path)
self.failUnlessEqual(warning_class, ' ' + UserWarning.__name__)
self.failUnlessEqual(message, ' ' + text)
expected_line = ' ' + linecache.getline(path, line).strip() + '\n'
assert expected_line
self.failUnlessEqual(second_line, expected_line)
class WarningsDisplayTests(unittest.TestCase):
"""Test the displaying of warnings and the ability to overload functions
related to displaying warnings."""
def test_formatwarning(self):
message = "msg"
category = Warning
file_name = os.path.splitext(warning_tests.__file__)[0] + '.py'
line_num = 3
file_line = linecache.getline(file_name, line_num).strip()
format = "%s:%s: %s: %s\n %s\n"
expect = format % (file_name, line_num, category.__name__, message,
file_line)
self.failUnlessEqual(expect, self.module.formatwarning(message,
category, file_name, line_num))
# Test the 'line' argument.
file_line += " for the win!"
expect = format % (file_name, line_num, category.__name__, message,
file_line)
self.failUnlessEqual(expect, self.module.formatwarning(message,
category, file_name, line_num, file_line))
def test_showwarning(self):
file_name = os.path.splitext(warning_tests.__file__)[0] + '.py'
line_num = 3
expected_file_line = linecache.getline(file_name, line_num).strip()
message = 'msg'
category = Warning
file_object = StringIO.StringIO()
expect = self.module.formatwarning(message, category, file_name,
line_num)
self.module.showwarning(message, category, file_name, line_num,
file_object)
self.failUnlessEqual(file_object.getvalue(), expect)
# Test 'line' argument.
expected_file_line += "for the win!"
expect = self.module.formatwarning(message, category, file_name,
line_num, expected_file_line)
file_object = StringIO.StringIO()
self.module.showwarning(message, category, file_name, line_num,
file_object, expected_file_line)
self.failUnlessEqual(expect, file_object.getvalue())
class CWarningsDisplayTests(WarningsDisplayTests):
module = c_warnings
class PyWarningsDisplayTests(WarningsDisplayTests):
module = py_warnings
def test_main():
# Obscure hack so that this test passes after reloads or repeated calls
# to test_main (regrtest -R).
if '__warningregistry__' in globals():
del globals()['__warningregistry__']
if hasattr(warning_tests, '__warningregistry__'):
del warning_tests.__warningregistry__
if hasattr(sys, '__warningregistry__'):
del sys.__warningregistry__
test_support.run_unittest(CFilterTests, PyFilterTests,
CWarnTests, PyWarnTests,
CWCmdLineTests, PyWCmdLineTests,
_WarningsTests,
CWarningsDisplayTests, PyWarningsDisplayTests,
)
if __name__ == "__main__":
test_main()