Lib/test/test_support.py

   1 """Supporting definitions for the Python regression test."""
   2
   3 if __name__ != 'test.test_support':
   4     raise ImportError, 'test_support must be imported from the test package'
   5
   6 import sys
   7
   8 class Error(Exception):
   9     """Base class for regression test exceptions."""
  10
  11 class TestFailed(Error):
  12     """Test failed."""
  13
  14 class TestSkipped(Error):
  15     """Test skipped.
  16
  17     This can be raised to indicate that a test was deliberatly
  18     skipped, but not because a feature wasn't available.  For
  19     example, if some resource can't be used, such as the network
  20     appears to be unavailable, this should be raised instead of
  21     TestFailed.
  22     """
  23
  24 verbose = 1              # Flag set to 0 by regrtest.py
  25 use_resources = None       # Flag set to [] by regrtest.py
  26
  27 # _original_stdout is meant to hold stdout at the time regrtest began.
  28 # This may be "the real" stdout, or IDLE's emulation of stdout, or whatever.
  29 # The point is to have some flavor of stdout the user can actually see.
  30 _original_stdout = None
  31 def record_original_stdout(stdout):
  32     global _original_stdout
  33     _original_stdout = stdout
  34
  35 def get_original_stdout():
  36     return _original_stdout or sys.stdout
  37
  38 def unload(name):
  39     try:
  40         del sys.modules[name]
  41     except KeyError:
  42         pass
  43
  44 def forget(modname):
  45     unload(modname)
  46     import os
  47     for dirname in sys.path:
  48         try:
  49             os.unlink(os.path.join(dirname, modname + '.pyc'))
  50         except os.error:
  51             pass
  52
  53 def requires(resource, msg=None):
  54     if use_resources is not None and resource not in use_resources:
  55         if msg is None:
  56             msg = "Use of the `%s' resource not enabled" % resource
  57         raise TestSkipped(msg)
  58
  59 FUZZ = 1e-6
  60
  61 def fcmp(x, y): # fuzzy comparison function
  62     if type(x) == type(0.0) or type(y) == type(0.0):
  63         try:
  64             x, y = coerce(x, y)
  65             fuzz = (abs(x) + abs(y)) * FUZZ
  66             if abs(x-y) <= fuzz:
  67                 return 0
  68         except:
  69             pass
  70     elif type(x) == type(y) and type(x) in (type(()), type([])):
  71         for i in range(min(len(x), len(y))):
  72             outcome = fcmp(x[i], y[i])
  73             if outcome != 0:
  74                 return outcome
  75         return cmp(len(x), len(y))
  76     return cmp(x, y)
  77
  78 try:
  79     unicode
  80     have_unicode = 1
  81 except NameError:
  82     have_unicode = 0
  83
  84 import os
  85 # Filename used for testing
  86 if os.name == 'java':
  87     # Jython disallows @ in module names
  88     TESTFN = '$test'
  89 elif os.name != 'riscos':
  90     TESTFN = '@test'
  91     # Unicode name only used if TEST_FN_ENCODING exists for the platform.
  92     if have_unicode:
  93         TESTFN_UNICODE=unicode("@test-\xe0\xf2", "latin-1") # 2 latin characters.
  94         if os.name=="nt":
  95             TESTFN_ENCODING="mbcs"
  96 else:
  97     TESTFN = 'test'
  98 del os
  99
 100 from os import unlink
 101
 102 def findfile(file, here=__file__):
 103     import os
 104     if os.path.isabs(file):
 105         return file
 106     path = sys.path
 107     path = [os.path.dirname(here)] + path
 108     for dn in path:
 109         fn = os.path.join(dn, file)
 110         if os.path.exists(fn): return fn
 111     return file
 112
 113 def verify(condition, reason='test failed'):
 114     """Verify that condition is true. If not, raise TestFailed.
 115
 116        The optional argument reason can be given to provide
 117        a better error text.
 118     """
 119
 120     if not condition:
 121         raise TestFailed(reason)
 122
 123 def vereq(a, b):
 124     """Raise TestFailed if a == b is false.
 125
 126     This is better than verify(a == b) because, in case of failure, the
 127     error message incorporates repr(a) and repr(b) so you can see the
 128     inputs.
 129
 130     Note that "not (a == b)" isn't necessarily the same as "a != b"; the
 131     former is tested.
 132     """
 133
 134     if not (a == b):
 135         raise TestFailed, "%r == %r" % (a, b)
 136
 137 def sortdict(dict):
 138     "Like repr(dict), but in sorted order."
 139     items = dict.items()
 140     items.sort()
 141     reprpairs = ["%r: %r" % pair for pair in items]
 142     withcommas = ", ".join(reprpairs)
 143     return "{%s}" % withcommas
 144
 145 def check_syntax(statement):
 146     try:
 147         compile(statement, '<string>', 'exec')
 148     except SyntaxError:
 149         pass
 150     else:
 151         print 'Missing SyntaxError: "%s"' % statement
 152
 153
 154
 155 #=======================================================================
 156 # Preliminary PyUNIT integration.
 157
 158 import unittest
 159
 160
 161 class BasicTestRunner:
 162     def run(self, test):
 163         result = unittest.TestResult()
 164         test(result)
 165         return result
 166
 167
 168 def run_suite(suite, testclass=None):
 169     """Run tests from a unittest.TestSuite-derived class."""
 170     if verbose:
 171         runner = unittest.TextTestRunner(sys.stdout, verbosity=2)
 172     else:
 173         runner = BasicTestRunner()
 174
 175     result = runner.run(suite)
 176     if not result.wasSuccessful():
 177         if len(result.errors) == 1 and not result.failures:
 178             err = result.errors[0][1]
 179         elif len(result.failures) == 1 and not result.errors:
 180             err = result.failures[0][1]
 181         else:
 182             if testclass is None:
 183                 msg = "errors occurred; run in verbose mode for details"
 184             else:
 185                 msg = "errors occurred in %s.%s" \
 186                       % (testclass.__module__, testclass.__name__)
 187             raise TestFailed(msg)
 188         raise TestFailed(err)
 189
 190
 191 def run_unittest(testclass):
 192     """Run tests from a unittest.TestCase-derived class."""
 193     run_suite(unittest.makeSuite(testclass), testclass)
 194
 195
 196 #=======================================================================
 197 # doctest driver.
 198
 199 def run_doctest(module, verbosity=None):
 200     """Run doctest on the given module.  Return (#failures, #tests).
 201
 202     If optional argument verbosity is not specified (or is None), pass
 203     test_support's belief about verbosity on to doctest.  Else doctest's
 204     usual behavior is used (it searches sys.argv for -v).
 205     """
 206
 207     import doctest
 208
 209     if verbosity is None:
 210         verbosity = verbose
 211     else:
 212         verbosity = None
 213
 214     # Direct doctest output (normally just errors) to real stdout; doctest
 215     # output shouldn't be compared by regrtest.
 216     save_stdout = sys.stdout
 217     sys.stdout = get_original_stdout()
 218     try:
 219         f, t = doctest.testmod(module, verbose=verbosity)
 220         if f:
 221             raise TestFailed("%d of %d doctests failed" % (f, t))
 222         return f, t
 223     finally:
 224         sys.stdout = save_stdout