Lib/test/test_support.py

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