git.maemo.org Git - theonering/blob - tests/test_utils.py

   1 #!/usr/bin/env python
   2
   3
   4 from __future__ import with_statement
   5
   6 import inspect
   7 import contextlib
   8 import functools
   9
  10
  11 def TODO(func):
  12         """
  13         unittest test method decorator that ignores
  14         exceptions raised by test
  15
  16         Used to annotate test methods for code that may
  17         not be written yet.  Ignores failures in the
  18         annotated test method; fails if the text
  19         unexpectedly succeeds.
  20         !author http://kbyanc.blogspot.com/2007/06/pythons-unittest-module-aint-that-bad.html
  21
  22         Example:
  23         >>> import unittest
  24         >>> class ExampleTestCase(unittest.TestCase):
  25         ...     @TODO
  26         ...     def testToDo(self):
  27         ...             MyModule.DoesNotExistYet('boo')
  28         ...
  29         """
  30
  31         @functools.wraps(func)
  32         def wrapper(*args, **kw):
  33                 try:
  34                         func(*args, **kw)
  35                         succeeded = True
  36                 except:
  37                         succeeded = False
  38                 assert succeeded is False, \
  39                         "%s marked TODO but passed" % func.__name__
  40         return wrapper
  41
  42
  43 def PlatformSpecific(platformList):
  44         """
  45         unittest test method decorator that only
  46         runs test method if os.name is in the
  47         given list of platforms
  48         !author http://kbyanc.blogspot.com/2007/06/pythons-unittest-module-aint-that-bad.html
  49         Example:
  50         >>> import unittest
  51         >>> class ExampleTestCase(unittest.TestCase):
  52         ...     @PlatformSpecific(('mac', ))
  53         ...     def testMacOnly(self):
  54         ...             MyModule.SomeMacSpecificFunction()
  55         ...
  56         """
  57
  58         def decorator(func):
  59                 import os
  60
  61                 @functools.wraps(func)
  62                 def wrapper(*args, **kw):
  63                         if os.name in platformList:
  64                                 return func(*args, **kw)
  65                 return wrapper
  66         return decorator
  67
  68
  69 def CheckReferences(func):
  70         """
  71         !author http://kbyanc.blogspot.com/2007/06/pythons-unittest-module-aint-that-bad.html
  72         """
  73
  74         @functools.wraps(func)
  75         def wrapper(*args, **kw):
  76                 refCounts = []
  77                 for i in range(5):
  78                         func(*args, **kw)
  79                         refCounts.append(XXXGetRefCount())
  80                 assert min(refCounts) != max(refCounts), "Reference counts changed - %r" % refCounts
  81
  82         return wrapper
  83
  84
  85 @contextlib.contextmanager
  86 def expected(exception):
  87         """
  88         >>> with expected2(ZeroDivisionError):
  89         ...     1 / 0
  90         >>> with expected2(AssertionError("expected ZeroDivisionError to have been thrown")):
  91         ...     with expected(ZeroDivisionError):
  92         ...             1 / 2
  93         Traceback (most recent call last):
  94                 File "/usr/lib/python2.5/doctest.py", line 1228, in __run
  95                         compileflags, 1) in test.globs
  96                 File "<doctest libraries.recipes.context.expected[1]>", line 3, in <module>
  97                         1 / 2
  98                 File "/media/data/Personal/Development/bzr/Recollection-trunk/src/libraries/recipes/context.py", line 139, in __exit__
  99                         assert t is not None, ("expected {0:%s} to have been thrown" % (self._t.__name__))
 100         AssertionError: expected {0:ZeroDivisionError} to have been thrown
 101         >>> with expected2(Exception("foo")):
 102         ...     raise Exception("foo")
 103         >>> with expected2(Exception("bar")):
 104         ...     with expected(Exception("foo")): # this won't catch it
 105         ...             raise Exception("bar")
 106         ...     assert False, "should not see me"
 107         >>> with expected2(Exception("can specify")):
 108         ...     raise Exception("can specify prefixes")
 109         >>> with expected2(Exception("Base class fun")):
 110         True
 111         >>> True
 112         False
 113         """
 114         if isinstance(exception, Exception):
 115                 excType, excValue = type(exception), str(exception)
 116         elif isinstance(exception, type):
 117                 excType, excValue = exception, ""
 118
 119         try:
 120                 yield
 121         except Exception, e:
 122                 if not (excType in inspect.getmro(type(e)) and str(e).startswith(excValue)):
 123                         raise
 124         else:
 125                 raise AssertionError("expected {0:%s} to have been thrown" % excType.__name__)
 126
 127
 128 if __name__ == "__main__":
 129         import doctest
 130         doctest.testmod()