Lib/test/test_traceback.py

   1 """Test cases for traceback module"""
   2
   3 import unittest
   4 from test.test_support import run_unittest, is_jython
   5
   6 import traceback
   7
   8 class TracebackCases(unittest.TestCase):
   9     # For now, a very minimal set of tests.  I want to be sure that
  10     # formatting of SyntaxErrors works based on changes for 2.1.
  11
  12     def get_exception_format(self, func, exc):
  13         try:
  14             func()
  15         except exc, value:
  16             return traceback.format_exception_only(exc, value)
  17         else:
  18             raise ValueError, "call did not raise exception"
  19
  20     def syntax_error_with_caret(self):
  21         compile("def fact(x):\n\treturn x!\n", "?", "exec")
  22
  23     def syntax_error_without_caret(self):
  24         # XXX why doesn't compile raise the same traceback?
  25         import test.badsyntax_nocaret
  26
  27     def syntax_error_bad_indentation(self):
  28         compile("def spam():\n  print 1\n print 2", "?", "exec")
  29
  30     def test_caret(self):
  31         err = self.get_exception_format(self.syntax_error_with_caret,
  32                                         SyntaxError)
  33         self.assert_(len(err) == 4)
  34         self.assert_("^" in err[2]) # third line has caret
  35         self.assert_(err[1].strip() == "return x!")
  36
  37     def test_nocaret(self):
  38         if is_jython:
  39             # jython adds a caret in this case (why shouldn't it?)
  40             return
  41         err = self.get_exception_format(self.syntax_error_without_caret,
  42                                         SyntaxError)
  43         self.assert_(len(err) == 3)
  44         self.assert_(err[1].strip() == "[x for x in x] = x")
  45
  46     def test_bad_indentation(self):
  47         err = self.get_exception_format(self.syntax_error_bad_indentation,
  48                                         IndentationError)
  49         self.assert_(len(err) == 4)
  50         self.assert_("^" in err[2])
  51         self.assert_(err[1].strip() == "print 2")
  52
  53     def test_bug737473(self):
  54         import sys, os, tempfile, time
  55
  56         savedpath = sys.path[:]
  57         testdir = tempfile.mkdtemp()
  58         try:
  59             sys.path.insert(0, testdir)
  60             testfile = os.path.join(testdir, 'test_bug737473.py')
  61             print >> open(testfile, 'w'), """
  62 def test():
  63     raise ValueError"""
  64
  65             if 'test_bug737473' in sys.modules:
  66                 del sys.modules['test_bug737473']
  67             import test_bug737473
  68
  69             try:
  70                 test_bug737473.test()
  71             except ValueError:
  72                 # this loads source code to linecache
  73                 traceback.extract_tb(sys.exc_traceback)
  74
  75             # If this test runs too quickly, test_bug737473.py's mtime
  76             # attribute will remain unchanged even if the file is rewritten.
  77             # Consequently, the file would not reload.  So, added a sleep()
  78             # delay to assure that a new, distinct timestamp is written.
  79             # Since WinME with FAT32 has multisecond resolution, more than
  80             # three seconds are needed for this test to pass reliably :-(
  81             time.sleep(4)
  82
  83             print >> open(testfile, 'w'), """
  84 def test():
  85     raise NotImplementedError"""
  86             reload(test_bug737473)
  87             try:
  88                 test_bug737473.test()
  89             except NotImplementedError:
  90                 src = traceback.extract_tb(sys.exc_traceback)[-1][-1]
  91                 self.failUnlessEqual(src, 'raise NotImplementedError')
  92         finally:
  93             sys.path[:] = savedpath
  94             for f in os.listdir(testdir):
  95                 os.unlink(os.path.join(testdir, f))
  96             os.rmdir(testdir)
  97
  98     def test_members(self):
  99         # Covers Python/structmember.c::listmembers()
 100         try:
 101             1/0
 102         except:
 103             import sys
 104             sys.exc_traceback.__members__
 105
 106 def test_main():
 107     run_unittest(TracebackCases)
 108
 109
 110 if __name__ == "__main__":
 111     test_main()