"""
tl;dr: all code code is licensed under simplified BSD, unless stated otherwise.
Unless stated otherwise in the source files, all code is copyright 2010 David
Wolever <david@wolever.net>. All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:
1. Redistributions of source code must retain the above copyright notice,
this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright notice,
this list of conditions and the following disclaimer in the documentation
and/or other materials provided with the distribution.
THIS SOFTWARE IS PROVIDED BY <COPYRIGHT HOLDER> ``AS IS'' AND ANY EXPRESS OR
IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
EVENT SHALL <COPYRIGHT HOLDER> OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
The views and conclusions contained in the software and documentation are those
of the authors and should not be interpreted as representing official policies,
either expressed or implied, of David Wolever.
"""
import re
import sys
import inspect
import warnings
from functools import wraps
from types import MethodType as MethodType
from collections import namedtuple
try:
from collections import OrderedDict as MaybeOrderedDict
except ImportError:
MaybeOrderedDict = dict
from unittest import TestCase
PY3 = sys.version_info[0] == 3
PY2 = sys.version_info[0] == 2
if PY3:
# Python 3 doesn't have an InstanceType, so just use a dummy type.
class InstanceType():
pass
lzip = lambda *a: list(zip(*a))
text_type = str
string_types = str,
bytes_type = bytes
def make_method(func, instance, type):
if instance is None:
return func
return MethodType(func, instance)
else:
from types import InstanceType
lzip = zip
text_type = unicode
bytes_type = str
string_types = basestring,
def make_method(func, instance, type):
return MethodType(func, instance, type)
_param = namedtuple("param", "args kwargs")
class param(_param):
""" Represents a single parameter to a test case.
For example::
>>> p = param("foo", bar=16)
>>> p
param("foo", bar=16)
>>> p.args
('foo', )
>>> p.kwargs
{'bar': 16}
Intended to be used as an argument to ``@parameterized``::
@parameterized([
param("foo", bar=16),
])
def test_stuff(foo, bar=16):
pass
"""
def __new__(cls, *args , **kwargs):
return _param.__new__(cls, args, kwargs)
@classmethod
def explicit(cls, args=None, kwargs=None):
""" Creates a ``param`` by explicitly specifying ``args`` and
``kwargs``::
>>> param.explicit([1,2,3])
param(*(1, 2, 3))
>>> param.explicit(kwargs={"foo": 42})
param(*(), **{"foo": "42"})
"""
args = args or ()
kwargs = kwargs or {}
return cls(*args, **kwargs)
@classmethod
def from_decorator(cls, args):
""" Returns an instance of ``param()`` for ``@parameterized`` argument
``args``::
>>> param.from_decorator((42, ))
param(args=(42, ), kwargs={})
>>> param.from_decorator("foo")
param(args=("foo", ), kwargs={})
"""
if isinstance(args, param):
return args
elif isinstance(args, string_types):
args = (args, )
try:
return cls(*args)
except TypeError as e:
if "after * must be" not in str(e):
raise
raise TypeError(
"Parameters must be tuples, but %r is not (hint: use '(%r, )')"
%(args, args),
)
def __repr__(self):
return "param(*%r, **%r)" %self
class QuietOrderedDict(MaybeOrderedDict):
""" When OrderedDict is available, use it to make sure that the kwargs in
doc strings are consistently ordered. """
__str__ = dict.__str__
__repr__ = dict.__repr__
def parameterized_argument_value_pairs(func, p):
"""Return tuples of parameterized arguments and their values.
This is useful if you are writing your own doc_func
function and need to know the values for each parameter name::
>>> def func(a, foo=None, bar=42, **kwargs): pass
>>> p = param(1, foo=7, extra=99)
>>> parameterized_argument_value_pairs(func, p)
[("a", 1), ("foo", 7), ("bar", 42), ("**kwargs", {"extra": 99})]
If the function's first argument is named ``self`` then it will be
ignored::
>>> def func(self, a): pass
>>> p = param(1)
>>> parameterized_argument_value_pairs(func, p)
[("a", 1)]
Additionally, empty ``*args`` or ``**kwargs`` will be ignored::
>>> def func(foo, *args): pass
>>> p = param(1)
>>> parameterized_argument_value_pairs(func, p)
[("foo", 1)]
>>> p = param(1, 16)
>>> parameterized_argument_value_pairs(func, p)
[("foo", 1), ("*args", (16, ))]
"""
argspec = inspect.getargspec(func)
arg_offset = 1 if argspec.args[:1] == ["self"] else 0
named_args = argspec.args[arg_offset:]
result = lzip(named_args, p.args)
named_args = argspec.args[len(result) + arg_offset:]
varargs = p.args[len(result):]
result.extend([
(name, p.kwargs.get(name, default))
for (name, default)
in zip(named_args, argspec.defaults or [])
])
seen_arg_names = set([ n for (n, _) in result ])
keywords = QuietOrderedDict(sorted([
(name, p.kwargs[name])
for name in p.kwargs
if name not in seen_arg_names
]))
if varargs:
result.append(("*%s" %(argspec.varargs, ), tuple(varargs)))
if keywords:
result.append(("**%s" %(argspec.keywords, ), keywords))
return result
def short_repr(x, n=64):
""" A shortened repr of ``x`` which is guaranteed to be ``unicode``::
>>> short_repr("foo")
u"foo"
>>> short_repr("123456789", n=4)
u"12...89"
"""
x_repr = repr(x)
if isinstance(x_repr, bytes_type):
try:
x_repr = text_type(x_repr, "utf-8")
except UnicodeDecodeError:
x_repr = text_type(x_repr, "latin1")
if len(x_repr) > n:
x_repr = x_repr[:n//2] + "..." + x_repr[len(x_repr) - n//2:]
return x_repr
def default_doc_func(func, num, p):
if func.__doc__ is None:
return None
all_args_with_values = parameterized_argument_value_pairs(func, p)
# Assumes that the function passed is a bound method.
descs = ["%s=%s" %(n, short_repr(v)) for n, v in all_args_with_values]
# The documentation might be a multiline string, so split it
# and just work with the first string, ignoring the period
# at the end if there is one.
first, nl, rest = func.__doc__.lstrip().partition("\n")
suffix = ""
if first.endswith("."):
suffix = "."
first = first[:-1]
args = "%s[with %s]" %(len(first) and " " or "", ", ".join(descs))
return "".join([first.rstrip(), args, suffix, nl, rest])
def default_name_func(func, num, p):
base_name = func.__name__
name_suffix = "_%s" %(num, )
if len(p.args) > 0 and isinstance(p.args[0], string_types):
name_suffix += "_" + parameterized.to_safe_name(p.args[0])
return base_name + name_suffix
_test_runner_override = None
_test_runner_guess = False
_test_runners = set(["unittest", "unittest2", "nose", "nose2", "pytest"])
_test_runner_aliases = {
"_pytest": "pytest",
}
def set_test_runner(name):
global _test_runner_override
if name not in _test_runners:
raise TypeError(
"Invalid test runner: %r (must be one of: %s)"
%(name, ", ".join(_test_runners)),
)
_test_runner_override = name
def detect_runner():
""" Guess which test runner we're using by traversing the stack and looking
for the first matching module. This *should* be reasonably safe, as
it's done during test disocvery where the test runner should be the
stack frame immediately outside. """
if _test_runner_override is not None:
return _test_runner_override
global _test_runner_guess
if _test_runner_guess is False:
stack = inspect.stack()
for record in reversed(stack):
frame = record[0]
module = frame.f_globals.get("__name__").partition(".")[0]
if module in _test_runner_aliases:
module = _test_runner_aliases[module]
if module in _test_runners:
_test_runner_guess = module
break
if record[1].endswith("python2.6/unittest.py"):
_test_runner_guess = "unittest"
break
else:
_test_runner_guess = None
return _test_runner_guess
class parameterized(object):
""" Parameterize a test case::
class TestInt(object):
@parameterized([
("A", 10),
("F", 15),
param("10", 42, base=42)
])
def test_int(self, input, expected, base=16):
actual = int(input, base=base)
assert_equal(actual, expected)
@parameterized([
(2, 3, 5)
(3, 5, 8),
])
def test_add(a, b, expected):
assert_equal(a + b, expected)
"""
def __init__(self, input, doc_func=None):
self.get_input = self.input_as_callable(input)
self.doc_func = doc_func or default_doc_func
def __call__(self, test_func):
self.assert_not_in_testcase_subclass()
@wraps(test_func)
def wrapper(test_self=None):
test_cls = test_self and type(test_self)
if test_self is not None:
if issubclass(test_cls, InstanceType):
raise TypeError((
"@parameterized can't be used with old-style classes, but "
"%r has an old-style class. Consider using a new-style "
"class, or '@parameterized.expand' "
"(see http://stackoverflow.com/q/54867/71522 for more "
"information on old-style classes)."
) %(test_self, ))
original_doc = wrapper.__doc__
for num, args in enumerate(wrapper.parameterized_input):
p = param.from_decorator(args)
unbound_func, nose_tuple = self.param_as_nose_tuple(test_self, test_func, num, p)
try:
wrapper.__doc__ = nose_tuple[0].__doc__
# Nose uses `getattr(instance, test_func.__name__)` to get
# a method bound to the test instance (as opposed to a
# method bound to the instance of the class created when
# tests were being enumerated). Set a value here to make
# sure nose can get the correct test method.
if test_self is not None:
setattr(test_cls, test_func.__name__, unbound_func)
yield nose_tuple
finally:
if test_self is not None:
delattr(test_cls, test_func.__name__)
wrapper.__doc__ = original_doc
wrapper.parameterized_input = self.get_input()
wrapper.parameterized_func = test_func
test_func.__name__ = "_parameterized_original_%s" %(test_func.__name__, )
return wrapper
def param_as_nose_tuple(self, test_self, func, num, p):
nose_func = wraps(func)(lambda *args: func(*args[:-1], **args[-1]))
nose_func.__doc__ = self.doc_func(func, num, p)
# Track the unbound function because we need to setattr the unbound
# function onto the class for nose to work (see comments above), and
# Python 3 doesn't let us pull the function out of a bound method.
unbound_func = nose_func
if test_self is not None:
# Under nose on Py2 we need to return an unbound method to make
# sure that the `self` in the method is properly shared with the
# `self` used in `setUp` and `tearDown`. But only there. Everyone
# else needs a bound method.
func_self = (
None if PY2 and detect_runner() == "nose" else
test_self
)
nose_func = make_method(nose_func, func_self, type(test_self))
return unbound_func, (nose_func, ) + p.args + (p.kwargs or {}, )
def assert_not_in_testcase_subclass(self):
parent_classes = self._terrible_magic_get_defining_classes()
if any(issubclass(cls, TestCase) for cls in parent_classes):
raise Exception("Warning: '@parameterized' tests won't work "
"inside subclasses of 'TestCase' - use "
"'@parameterized.expand' instead.")
def _terrible_magic_get_defining_classes(self):
""" Returns the set of parent classes of the class currently being defined.
Will likely only work if called from the ``parameterized`` decorator.
This function is entirely @brandon_rhodes's fault, as he suggested
the implementation: http://stackoverflow.com/a/8793684/71522
"""
stack = inspect.stack()
if len(stack) <= 4:
return []
frame = stack[4]
code_context = frame[4] and frame[4][0].strip()
if not (code_context and code_context.startswith("class ")):
return []
_, _, parents = code_context.partition("(")
parents, _, _ = parents.partition(")")
return eval("[" + parents + "]", frame[0].f_globals, frame[0].f_locals)
@classmethod
def input_as_callable(cls, input):
if callable(input):
return lambda: cls.check_input_values(input())
input_values = cls.check_input_values(input)
return lambda: input_values
@classmethod
def check_input_values(cls, input_values):
# Explicitly convery non-list inputs to a list so that:
# 1. A helpful exception will be raised if they aren't iterable, and
# 2. Generators are unwrapped exactly once (otherwise `nosetests
# --processes=n` has issues; see:
# https://github.com/wolever/nose-parameterized/pull/31)
if not isinstance(input_values, list):
input_values = list(input_values)
return [ param.from_decorator(p) for p in input_values ]
@classmethod
def expand(cls, input, name_func=None, doc_func=None, **legacy):
""" A "brute force" method of parameterizing test cases. Creates new
test cases and injects them into the namespace that the wrapped
function is being defined in. Useful for parameterizing tests in
subclasses of 'UnitTest', where Nose test generators don't work.
>>> @parameterized.expand([("foo", 1, 2)])
... def test_add1(name, input, expected):
... actual = add1(input)
... assert_equal(actual, expected)
...
>>> locals()
... 'test_add1_foo_0': <function ...> ...
>>>
"""
if "testcase_func_name" in legacy:
warnings.warn("testcase_func_name= is deprecated; use name_func=",
DeprecationWarning, stacklevel=2)
if not name_func:
name_func = legacy["testcase_func_name"]
if "testcase_func_doc" in legacy:
warnings.warn("testcase_func_doc= is deprecated; use doc_func=",
DeprecationWarning, stacklevel=2)
if not doc_func:
doc_func = legacy["testcase_func_doc"]
doc_func = doc_func or default_doc_func
name_func = name_func or default_name_func
def parameterized_expand_wrapper(f, instance=None):
stack = inspect.stack()
frame = stack[1]
frame_locals = frame[0].f_locals
paramters = cls.input_as_callable(input)()
for num, p in enumerate(paramters):
name = name_func(f, num, p)
frame_locals[name] = cls.param_as_standalone_func(p, f, name)
frame_locals[name].__doc__ = doc_func(f, num, p)
f.__test__ = False
return parameterized_expand_wrapper
@classmethod
def param_as_standalone_func(cls, p, func, name):
@wraps(func)
def standalone_func(*a):
return func(*(a + p.args), **p.kwargs)
standalone_func.__name__ = name
# place_as is used by py.test to determine what source file should be
# used for this test.
standalone_func.place_as = func
# Remove __wrapped__ because py.test will try to look at __wrapped__
# to determine which parameters should be used with this test case,
# and obviously we don't need it to do any parameterization.
try:
del standalone_func.__wrapped__
except AttributeError:
pass
return standalone_func
@classmethod
def to_safe_name(cls, s):
return str(re.sub("[^a-zA-Z0-9_]+", "_", s))