"""Test that the semantics relating to the 'fromlist' argument are correct."""
from .. import util
from import util
import unittest
class ReturnValue(unittest.TestCase):
"""The use of fromlist influences what import returns.
If direct ``import ...`` statement is used, the root module or package is
returned [import return]. But if fromlist is set, then the specified module
is actually returned (whether it is a relative import or not)
[from return].
"""
def test_return_from_import(self):
# [import return]
with util.mock_modules('pkg.__init__', 'pkg.module') as importer:
with util.import_state(meta_path=[importer]):
module = import_util.import_('pkg.module')
self.assertEquals(module.__name__, 'pkg')
def test_return_from_from_import(self):
# [from return]
with util.mock_modules('pkg.__init__', 'pkg.module')as importer:
with util.import_state(meta_path=[importer]):
module = import_util.import_('pkg.module', fromlist=['attr'])
self.assertEquals(module.__name__, 'pkg.module')
class HandlingFromlist(unittest.TestCase):
"""Using fromlist triggers different actions based on what is being asked
of it.
If fromlist specifies an object on a module, nothing special happens
[object case]. This is even true if the object does not exist [bad object].
If a package is being imported, then what is listed in fromlist may be
treated as a module to be imported [module]. But once again, even if
something in fromlist does not exist as a module, no error is thrown
[no module]. And this extends to what is contained in __all__ when '*' is
imported [using *]. And '*' does not need to be the only name in the
fromlist [using * with others].
"""
def test_object(self):
# [object case]
with util.mock_modules('module') as importer:
with util.import_state(meta_path=[importer]):
module = import_util.import_('module', fromlist=['attr'])
self.assertEquals(module.__name__, 'module')
def test_unexistent_object(self):
# [bad object]
with util.mock_modules('module') as importer:
with util.import_state(meta_path=[importer]):
module = import_util.import_('module', fromlist=['non_existent'])
self.assertEquals(module.__name__, 'module')
self.assertTrue(not hasattr(module, 'non_existent'))
def test_module_from_package(self):
# [module]
with util.mock_modules('pkg.__init__', 'pkg.module') as importer:
with util.import_state(meta_path=[importer]):
module = import_util.import_('pkg', fromlist=['module'])
self.assertEquals(module.__name__, 'pkg')
self.assertTrue(hasattr(module, 'module'))
self.assertEquals(module.module.__name__, 'pkg.module')
def test_no_module_from_package(self):
# [no module]
with util.mock_modules('pkg.__init__') as importer:
with util.import_state(meta_path=[importer]):
module = import_util.import_('pkg', fromlist='non_existent')
self.assertEquals(module.__name__, 'pkg')
self.assertTrue(not hasattr(module, 'non_existent'))
def test_empty_string(self):
with util.mock_modules('pkg.__init__', 'pkg.mod') as importer:
with util.import_state(meta_path=[importer]):
module = import_util.import_('pkg.mod', fromlist=[''])
self.assertEquals(module.__name__, 'pkg.mod')
def test_using_star(self):
# [using *]
with util.mock_modules('pkg.__init__', 'pkg.module') as mock:
with util.import_state(meta_path=[mock]):
mock['pkg'].__all__ = ['module']
module = import_util.import_('pkg', fromlist=['*'])
self.assertEquals(module.__name__, 'pkg')
self.assertTrue(hasattr(module, 'module'))
self.assertEqual(module.module.__name__, 'pkg.module')
def test_star_with_others(self):
# [using * with others]
context = util.mock_modules('pkg.__init__', 'pkg.module1', 'pkg.module2')
with context as mock:
with util.import_state(meta_path=[mock]):
mock['pkg'].__all__ = ['module1']
module = import_util.import_('pkg', fromlist=['module2', '*'])
self.assertEquals(module.__name__, 'pkg')
self.assertTrue(hasattr(module, 'module1'))
self.assertTrue(hasattr(module, 'module2'))
self.assertEquals(module.module1.__name__, 'pkg.module1')
self.assertEquals(module.module2.__name__, 'pkg.module2')
def test_main():
from test.support import run_unittest
run_unittest(ReturnValue, HandlingFromlist)
if __name__ == '__main__':
test_main()
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