Lib/test/test_pdb.py

   1 # A test suite for pdb; at the moment, this only validates skipping of
   2 # specified test modules (RFE #5142).
   3
   4 import imp
   5 import os
   6 import sys
   7 import doctest
   8 import tempfile
   9
  10 from test import test_support
  11 # This little helper class is essential for testing pdb under doctest.
  12 from test_doctest import _FakeInput
  13
  14
  15 class PdbTestInput(object):
  16     """Context manager that makes testing Pdb in doctests easier."""
  17
  18     def __init__(self, input):
  19         self.input = input
  20
  21     def __enter__(self):
  22         self.real_stdin = sys.stdin
  23         sys.stdin = _FakeInput(self.input)
  24
  25     def __exit__(self, *exc):
  26         sys.stdin = self.real_stdin
  27
  28
  29 def write(x):
  30     print x
  31
  32 def test_pdb_displayhook():
  33     """This tests the custom displayhook for pdb.
  34
  35     >>> def test_function(foo, bar):
  36     ...     import pdb; pdb.Pdb().set_trace()
  37     ...     pass
  38
  39     >>> with PdbTestInput([
  40     ...     'foo',
  41     ...     'bar',
  42     ...     'for i in range(5): write(i)',
  43     ...     'continue',
  44     ... ]):
  45     ...     test_function(1, None)
  46     > <doctest test.test_pdb.test_pdb_displayhook[0]>(3)test_function()
  47     -> pass
  48     (Pdb) foo
  49     1
  50     (Pdb) bar
  51     (Pdb) for i in range(5): write(i)
  52     0
  53     1
  54     2
  55     3
  56     4
  57     (Pdb) continue
  58     """
  59
  60
  61 def test_pdb_skip_modules():
  62     """This illustrates the simple case of module skipping.
  63
  64     >>> def skip_module():
  65     ...     import string
  66     ...     import pdb; pdb.Pdb(skip=['string*']).set_trace()
  67     ...     string.lower('FOO')
  68
  69     >>> with PdbTestInput([
  70     ...     'step',
  71     ...     'continue',
  72     ... ]):
  73     ...     skip_module()
  74     > <doctest test.test_pdb.test_pdb_skip_modules[0]>(4)skip_module()
  75     -> string.lower('FOO')
  76     (Pdb) step
  77     --Return--
  78     > <doctest test.test_pdb.test_pdb_skip_modules[0]>(4)skip_module()->None
  79     -> string.lower('FOO')
  80     (Pdb) continue
  81     """
  82
  83
  84 # Module for testing skipping of module that makes a callback
  85 mod = imp.new_module('module_to_skip')
  86 exec 'def foo_pony(callback): x = 1; callback(); return None' in mod.__dict__
  87
  88
  89 def test_pdb_skip_modules_with_callback():
  90     """This illustrates skipping of modules that call into other code.
  91
  92     >>> def skip_module():
  93     ...     def callback():
  94     ...         return None
  95     ...     import pdb; pdb.Pdb(skip=['module_to_skip*']).set_trace()
  96     ...     mod.foo_pony(callback)
  97
  98     >>> with PdbTestInput([
  99     ...     'step',
 100     ...     'step',
 101     ...     'step',
 102     ...     'step',
 103     ...     'step',
 104     ...     'continue',
 105     ... ]):
 106     ...     skip_module()
 107     ...     pass  # provides something to "step" to
 108     > <doctest test.test_pdb.test_pdb_skip_modules_with_callback[0]>(5)skip_module()
 109     -> mod.foo_pony(callback)
 110     (Pdb) step
 111     --Call--
 112     > <doctest test.test_pdb.test_pdb_skip_modules_with_callback[0]>(2)callback()
 113     -> def callback():
 114     (Pdb) step
 115     > <doctest test.test_pdb.test_pdb_skip_modules_with_callback[0]>(3)callback()
 116     -> return None
 117     (Pdb) step
 118     --Return--
 119     > <doctest test.test_pdb.test_pdb_skip_modules_with_callback[0]>(3)callback()->None
 120     -> return None
 121     (Pdb) step
 122     --Return--
 123     > <doctest test.test_pdb.test_pdb_skip_modules_with_callback[0]>(5)skip_module()->None
 124     -> mod.foo_pony(callback)
 125     (Pdb) step
 126     > <doctest test.test_pdb.test_pdb_skip_modules_with_callback[1]>(10)<module>()
 127     -> pass  # provides something to "step" to
 128     (Pdb) continue
 129     """
 130
 131
 132 def test_main():
 133     from test import test_pdb
 134     test_support.run_doctest(test_pdb, verbosity=True)
 135
 136
 137 if __name__ == '__main__':
 138     test_main()