1  import os
       2  import sys
       3  import shutil
       4  import string
       5  import random
       6  import tempfile
       7  import unittest
       8  
       9  from importlib.util import cache_from_source
      10  from test.support.os_helper import create_empty_file
      11  
      12  class ESC[4;38;5;81mTestImport(ESC[4;38;5;149munittestESC[4;38;5;149m.ESC[4;38;5;149mTestCase):
      13  
      14      def __init__(self, *args, **kw):
      15          self.package_name = 'PACKAGE_'
      16          while self.package_name in sys.modules:
      17              self.package_name += random.choice(string.ascii_letters)
      18          self.module_name = self.package_name + '.foo'
      19          unittest.TestCase.__init__(self, *args, **kw)
      20  
      21      def remove_modules(self):
      22          for module_name in (self.package_name, self.module_name):
      23              if module_name in sys.modules:
      24                  del sys.modules[module_name]
      25  
      26      def setUp(self):
      27          self.test_dir = tempfile.mkdtemp()
      28          sys.path.append(self.test_dir)
      29          self.package_dir = os.path.join(self.test_dir,
      30                                          self.package_name)
      31          os.mkdir(self.package_dir)
      32          create_empty_file(os.path.join(self.package_dir, '__init__.py'))
      33          self.module_path = os.path.join(self.package_dir, 'foo.py')
      34  
      35      def tearDown(self):
      36          shutil.rmtree(self.test_dir)
      37          self.assertNotEqual(sys.path.count(self.test_dir), 0)
      38          sys.path.remove(self.test_dir)
      39          self.remove_modules()
      40  
      41      def rewrite_file(self, contents):
      42          compiled_path = cache_from_source(self.module_path)
      43          if os.path.exists(compiled_path):
      44              os.remove(compiled_path)
      45          with open(self.module_path, 'w', encoding='utf-8') as f:
      46              f.write(contents)
      47  
      48      def test_package_import__semantics(self):
      49  
      50          # Generate a couple of broken modules to try importing.
      51  
      52          # ...try loading the module when there's a SyntaxError
      53          self.rewrite_file('for')
      54          try: __import__(self.module_name)
      55          except SyntaxError: pass
      56          else: raise RuntimeError('Failed to induce SyntaxError') # self.fail()?
      57          self.assertNotIn(self.module_name, sys.modules)
      58          self.assertFalse(hasattr(sys.modules[self.package_name], 'foo'))
      59  
      60          # ...make up a variable name that isn't bound in __builtins__
      61          var = 'a'
      62          while var in dir(__builtins__):
      63              var += random.choice(string.ascii_letters)
      64  
      65          # ...make a module that just contains that
      66          self.rewrite_file(var)
      67  
      68          try: __import__(self.module_name)
      69          except NameError: pass
      70          else: raise RuntimeError('Failed to induce NameError.')
      71  
      72          # ...now  change  the module  so  that  the NameError  doesn't
      73          # happen
      74          self.rewrite_file('%s = 1' % var)
      75          module = __import__(self.module_name).foo
      76          self.assertEqual(getattr(module, var), 1)
      77  
      78  
      79  if __name__ == "__main__":
      80      unittest.main()