test_ok1/py/_plugin/pytest_recwarn.py

122 lines
3.5 KiB
Python

"""
helpers for asserting deprecation and other warnings.
Example usage
---------------------
You can use the ``recwarn`` funcarg to track
warnings within a test function:
.. sourcecode:: python
def test_hello(recwarn):
from warnings import warn
warn("hello", DeprecationWarning)
w = recwarn.pop(DeprecationWarning)
assert issubclass(w.category, DeprecationWarning)
assert 'hello' in str(w.message)
assert w.filename
assert w.lineno
You can also call a global helper for checking
taht a certain function call yields a Deprecation
warning:
.. sourcecode:: python
import py
def test_global():
py.test.deprecated_call(myfunction, 17)
"""
import py
import os
def pytest_funcarg__recwarn(request):
"""Return a WarningsRecorder instance that provides these methods:
* ``pop(category=None)``: return last warning matching the category.
* ``clear()``: clear list of warnings
"""
warnings = WarningsRecorder()
request.addfinalizer(warnings.finalize)
return warnings
def pytest_namespace():
return {'deprecated_call': deprecated_call}
def deprecated_call(func, *args, **kwargs):
""" assert that calling func(*args, **kwargs)
triggers a DeprecationWarning.
"""
warningmodule = py.std.warnings
l = []
oldwarn_explicit = getattr(warningmodule, 'warn_explicit')
def warn_explicit(*args, **kwargs):
l.append(args)
oldwarn_explicit(*args, **kwargs)
oldwarn = getattr(warningmodule, 'warn')
def warn(*args, **kwargs):
l.append(args)
oldwarn(*args, **kwargs)
warningmodule.warn_explicit = warn_explicit
warningmodule.warn = warn
try:
ret = func(*args, **kwargs)
finally:
warningmodule.warn_explicit = warn_explicit
warningmodule.warn = warn
if not l:
#print warningmodule
__tracebackhide__ = True
raise AssertionError("%r did not produce DeprecationWarning" %(func,))
return ret
class RecordedWarning:
def __init__(self, message, category, filename, lineno, line):
self.message = message
self.category = category
self.filename = filename
self.lineno = lineno
self.line = line
class WarningsRecorder:
def __init__(self):
warningmodule = py.std.warnings
self.list = []
def showwarning(message, category, filename, lineno, line=0):
self.list.append(RecordedWarning(
message, category, filename, lineno, line))
try:
self.old_showwarning(message, category,
filename, lineno, line=line)
except TypeError:
# < python2.6
self.old_showwarning(message, category, filename, lineno)
self.old_showwarning = warningmodule.showwarning
warningmodule.showwarning = showwarning
def pop(self, cls=Warning):
""" pop the first recorded warning, raise exception if not exists."""
for i, w in enumerate(self.list):
if issubclass(w.category, cls):
return self.list.pop(i)
__tracebackhide__ = True
assert 0, "%r not found in %r" %(cls, self.list)
#def resetregistry(self):
# import warnings
# warnings.onceregistry.clear()
# warnings.__warningregistry__.clear()
def clear(self):
self.list[:] = []
def finalize(self):
py.std.warnings.showwarning = self.old_showwarning