vcs.maemo.org Git - ejpi/blob - src/libraries/recipes/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 class expected(object):
  86         """
  87         >>> with expected(ZeroDivisionError):
  88         ...     1 / 0
  89         >>> with expected(AssertionError("expected ZeroDivisionError to have been thrown")):
  90         ...     with expected(ZeroDivisionError):
  91         ...             1 / 2
  92         Traceback (most recent call last):
  93                 File "/usr/lib/python2.5/doctest.py", line 1228, in __run
  94                         compileflags, 1) in test.globs
  95                 File "<doctest libraries.recipes.context.expected[1]>", line 3, in <module>
  96                         1 / 2
  97                 File "/media/data/Personal/Development/bzr/Recollection-trunk/src/libraries/recipes/context.py", line 139, in __exit__
  98                         assert t is not None, ("expected {0:%s} to have been thrown" % (self._t.__name__))
  99         AssertionError: expected {0:ZeroDivisionError} to have been thrown
 100         >>> with expected(Exception("foo")):
 101         ...     raise Exception("foo")
 102         >>> with expected(Exception("bar")):
 103         ...     with expected(Exception("foo")): # this won't catch it
 104         ...             raise Exception("bar")
 105         ...     assert False, "should not see me"
 106         >>> with expected(Exception("can specify")):
 107         ...     raise Exception("can specify prefixes")
 108         >>> with expected(Exception("Base class fun")):
 109         ...     raise IndexError("Base class fun")
 110         """
 111
 112         def __init__(self, e):
 113                 if isinstance(e, Exception):
 114                         self._t, self._v = type(e), str(e)
 115                 elif isinstance(e, type):
 116                         self._t, self._v = e, ""
 117                 else:
 118                         raise Exception("usage: with expected(Exception): ... or "
 119                                                         "with expected(Exception(\"text\")): ...")
 120
 121         def __enter__(self):
 122                 try:
 123                         pass
 124                 except:
 125                         pass # this is a Python 3000 way of saying sys.exc_clear()
 126
 127         def __exit__(self, t, v, tb):
 128                 assert t is not None, ("expected {0:%s} to have been thrown" % (self._t.__name__))
 129                 return self._t in inspect.getmro(t) and str(v).startswith(self._v)