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-rw-r--r--lib/python2.7/test/test_importlib.py176
1 files changed, 176 insertions, 0 deletions
diff --git a/lib/python2.7/test/test_importlib.py b/lib/python2.7/test/test_importlib.py
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+++ b/lib/python2.7/test/test_importlib.py
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+import contextlib
+import imp
+import importlib
+import sys
+import unittest
+
+
+@contextlib.contextmanager
+def uncache(*names):
+ """Uncache a module from sys.modules.
+
+ A basic sanity check is performed to prevent uncaching modules that either
+ cannot/shouldn't be uncached.
+
+ """
+ for name in names:
+ if name in ('sys', 'marshal', 'imp'):
+ raise ValueError(
+ "cannot uncache {0} as it will break _importlib".format(name))
+ try:
+ del sys.modules[name]
+ except KeyError:
+ pass
+ try:
+ yield
+ finally:
+ for name in names:
+ try:
+ del sys.modules[name]
+ except KeyError:
+ pass
+
+
+@contextlib.contextmanager
+def import_state(**kwargs):
+ """Context manager to manage the various importers and stored state in the
+ sys module.
+
+ The 'modules' attribute is not supported as the interpreter state stores a
+ pointer to the dict that the interpreter uses internally;
+ reassigning to sys.modules does not have the desired effect.
+
+ """
+ originals = {}
+ try:
+ for attr, default in (('meta_path', []), ('path', []),
+ ('path_hooks', []),
+ ('path_importer_cache', {})):
+ originals[attr] = getattr(sys, attr)
+ if attr in kwargs:
+ new_value = kwargs[attr]
+ del kwargs[attr]
+ else:
+ new_value = default
+ setattr(sys, attr, new_value)
+ if len(kwargs):
+ raise ValueError(
+ 'unrecognized arguments: {0}'.format(kwargs.keys()))
+ yield
+ finally:
+ for attr, value in originals.items():
+ setattr(sys, attr, value)
+
+
+class mock_modules(object):
+
+ """A mock importer/loader."""
+
+ def __init__(self, *names):
+ self.modules = {}
+ for name in names:
+ if not name.endswith('.__init__'):
+ import_name = name
+ else:
+ import_name = name[:-len('.__init__')]
+ if '.' not in name:
+ package = None
+ elif import_name == name:
+ package = name.rsplit('.', 1)[0]
+ else:
+ package = import_name
+ module = imp.new_module(import_name)
+ module.__loader__ = self
+ module.__file__ = '<mock __file__>'
+ module.__package__ = package
+ module.attr = name
+ if import_name != name:
+ module.__path__ = ['<mock __path__>']
+ self.modules[import_name] = module
+
+ def __getitem__(self, name):
+ return self.modules[name]
+
+ def find_module(self, fullname, path=None):
+ if fullname not in self.modules:
+ return None
+ else:
+ return self
+
+ def load_module(self, fullname):
+ if fullname not in self.modules:
+ raise ImportError
+ else:
+ sys.modules[fullname] = self.modules[fullname]
+ return self.modules[fullname]
+
+ def __enter__(self):
+ self._uncache = uncache(*self.modules.keys())
+ self._uncache.__enter__()
+ return self
+
+ def __exit__(self, *exc_info):
+ self._uncache.__exit__(None, None, None)
+
+
+
+class ImportModuleTests(unittest.TestCase):
+
+ """Test importlib.import_module."""
+
+ def test_module_import(self):
+ # Test importing a top-level module.
+ with mock_modules('top_level') as mock:
+ with import_state(meta_path=[mock]):
+ module = importlib.import_module('top_level')
+ self.assertEqual(module.__name__, 'top_level')
+
+ def test_absolute_package_import(self):
+ # Test importing a module from a package with an absolute name.
+ pkg_name = 'pkg'
+ pkg_long_name = '{0}.__init__'.format(pkg_name)
+ name = '{0}.mod'.format(pkg_name)
+ with mock_modules(pkg_long_name, name) as mock:
+ with import_state(meta_path=[mock]):
+ module = importlib.import_module(name)
+ self.assertEqual(module.__name__, name)
+
+ def test_shallow_relative_package_import(self):
+ modules = ['a.__init__', 'a.b.__init__', 'a.b.c.__init__', 'a.b.c.d']
+ with mock_modules(*modules) as mock:
+ with import_state(meta_path=[mock]):
+ module = importlib.import_module('.d', 'a.b.c')
+ self.assertEqual(module.__name__, 'a.b.c.d')
+
+ def test_deep_relative_package_import(self):
+ # Test importing a module from a package through a relatve import.
+ modules = ['a.__init__', 'a.b.__init__', 'a.c']
+ with mock_modules(*modules) as mock:
+ with import_state(meta_path=[mock]):
+ module = importlib.import_module('..c', 'a.b')
+ self.assertEqual(module.__name__, 'a.c')
+
+ def test_absolute_import_with_package(self):
+ # Test importing a module from a package with an absolute name with
+ # the 'package' argument given.
+ pkg_name = 'pkg'
+ pkg_long_name = '{0}.__init__'.format(pkg_name)
+ name = '{0}.mod'.format(pkg_name)
+ with mock_modules(pkg_long_name, name) as mock:
+ with import_state(meta_path=[mock]):
+ module = importlib.import_module(name, pkg_name)
+ self.assertEqual(module.__name__, name)
+
+ def test_relative_import_wo_package(self):
+ # Relative imports cannot happen without the 'package' argument being
+ # set.
+ self.assertRaises(TypeError, importlib.import_module, '.support')
+
+
+def test_main():
+ from test.test_support import run_unittest
+ run_unittest(ImportModuleTests)
+
+
+if __name__ == '__main__':
+ test_main()