import unittest from warnings import catch_warnings from unittest.test.testmock.support import is_instance from unittest.mock import MagicMock, Mock, patch, sentinel, mock_open, call something = sentinel.Something something_else = sentinel.SomethingElse class WithTest(unittest.TestCase): def test_with_statement(self): with patch('%s.something' % __name__, sentinel.Something2): self.assertEqual(something, sentinel.Something2, "unpatched") self.assertEqual(something, sentinel.Something) def test_with_statement_exception(self): try: with patch('%s.something' % __name__, sentinel.Something2): self.assertEqual(something, sentinel.Something2, "unpatched") raise Exception('pow') except Exception: pass else: self.fail("patch swallowed exception") self.assertEqual(something, sentinel.Something) def test_with_statement_as(self): with patch('%s.something' % __name__) as mock_something: self.assertEqual(something, mock_something, "unpatched") self.assertTrue(is_instance(mock_something, MagicMock), "patching wrong type") self.assertEqual(something, sentinel.Something) def test_patch_object_with_statement(self): class Foo(object): something = 'foo' original = Foo.something with patch.object(Foo, 'something'): self.assertNotEqual(Foo.something, original, "unpatched") self.assertEqual(Foo.something, original) def test_with_statement_nested(self): with catch_warnings(record=True): with patch('%s.something' % __name__) as mock_something, patch('%s.something_else' % __name__) as mock_something_else: self.assertEqual(something, mock_something, "unpatched") self.assertEqual(something_else, mock_something_else, "unpatched") self.assertEqual(something, sentinel.Something) self.assertEqual(something_else, sentinel.SomethingElse) def test_with_statement_specified(self): with patch('%s.something' % __name__, sentinel.Patched) as mock_something: self.assertEqual(something, mock_something, "unpatched") self.assertEqual(mock_something, sentinel.Patched, "wrong patch") self.assertEqual(something, sentinel.Something) def testContextManagerMocking(self): mock = Mock() mock.__enter__ = Mock() mock.__exit__ = Mock() mock.__exit__.return_value = False with mock as m: self.assertEqual(m, mock.__enter__.return_value) mock.__enter__.assert_called_with() mock.__exit__.assert_called_with(None, None, None) def test_context_manager_with_magic_mock(self): mock = MagicMock() with self.assertRaises(TypeError): with mock: 'foo' + 3 mock.__enter__.assert_called_with() self.assertTrue(mock.__exit__.called) def test_with_statement_same_attribute(self): with patch('%s.something' % __name__, sentinel.Patched) as mock_something: self.assertEqual(something, mock_something, "unpatched") with patch('%s.something' % __name__) as mock_again: self.assertEqual(something, mock_again, "unpatched") self.assertEqual(something, mock_something, "restored with wrong instance") self.assertEqual(something, sentinel.Something, "not restored") def test_with_statement_imbricated(self): with patch('%s.something' % __name__) as mock_something: self.assertEqual(something, mock_something, "unpatched") with patch('%s.something_else' % __name__) as mock_something_else: self.assertEqual(something_else, mock_something_else, "unpatched") self.assertEqual(something, sentinel.Something) self.assertEqual(something_else, sentinel.SomethingElse) def test_dict_context_manager(self): foo = {} with patch.dict(foo, {'a': 'b'}): self.assertEqual(foo, {'a': 'b'}) self.assertEqual(foo, {}) with self.assertRaises(NameError): with patch.dict(foo, {'a': 'b'}): self.assertEqual(foo, {'a': 'b'}) raise NameError('Konrad') self.assertEqual(foo, {}) class TestMockOpen(unittest.TestCase): def test_mock_open(self): mock = mock_open() with patch('%s.open' % __name__, mock, create=True) as patched: self.assertIs(patched, mock) open('foo') mock.assert_called_once_with('foo') def test_mock_open_context_manager(self): mock = mock_open() handle = mock.return_value with patch('%s.open' % __name__, mock, create=True): with open('foo') as f: f.read() expected_calls = [call('foo'), call().__enter__(), call().read(), call().__exit__(None, None, None)] self.assertEqual(mock.mock_calls, expected_calls) self.assertIs(f, handle) def test_explicit_mock(self): mock = MagicMock() mock_open(mock) with patch('%s.open' % __name__, mock, create=True) as patched: self.assertIs(patched, mock) open('foo') mock.assert_called_once_with('foo') def test_read_data(self): mock = mock_open(read_data='foo') with patch('%s.open' % __name__, mock, create=True): h = open('bar') result = h.read() self.assertEqual(result, 'foo') def test_readline_data(self): # Check that readline will return all the lines from the fake file mock = mock_open(read_data='foo\nbar\nbaz\n') with patch('%s.open' % __name__, mock, create=True): h = open('bar') line1 = h.readline() line2 = h.readline() line3 = h.readline() self.assertEqual(line1, 'foo\n') self.assertEqual(line2, 'bar\n') self.assertEqual(line3, 'baz\n') # Check that we properly emulate a file that doesn't end in a newline mock = mock_open(read_data='foo') with patch('%s.open' % __name__, mock, create=True): h = open('bar') result = h.readline() self.assertEqual(result, 'foo') def test_readlines_data(self): # Test that emulating a file that ends in a newline character works mock = mock_open(read_data='foo\nbar\nbaz\n') with patch('%s.open' % __name__, mock, create=True): h = open('bar') result = h.readlines() self.assertEqual(result, ['foo\n', 'bar\n', 'baz\n']) # Test that files without a final newline will also be correctly # emulated mock = mock_open(read_data='foo\nbar\nbaz') with patch('%s.open' % __name__, mock, create=True): h = open('bar') result = h.readlines() self.assertEqual(result, ['foo\n', 'bar\n', 'baz']) def test_mock_open_read_with_argument(self): # At one point calling read with an argument was broken # for mocks returned by mock_open some_data = 'foo\nbar\nbaz' mock = mock_open(read_data=some_data) self.assertEqual(mock().read(10), some_data) def test_interleaved_reads(self): # Test that calling read, readline, and readlines pulls data # sequentially from the data we preload with mock = mock_open(read_data='foo\nbar\nbaz\n') with patch('%s.open' % __name__, mock, create=True): h = open('bar') line1 = h.readline() rest = h.readlines() self.assertEqual(line1, 'foo\n') self.assertEqual(rest, ['bar\n', 'baz\n']) mock = mock_open(read_data='foo\nbar\nbaz\n') with patch('%s.open' % __name__, mock, create=True): h = open('bar') line1 = h.readline() rest = h.read() self.assertEqual(line1, 'foo\n') self.assertEqual(rest, 'bar\nbaz\n') def test_overriding_return_values(self): mock = mock_open(read_data='foo') handle = mock() handle.read.return_value = 'bar' handle.readline.return_value = 'bar' handle.readlines.return_value = ['bar'] self.assertEqual(handle.read(), 'bar') self.assertEqual(handle.readline(), 'bar') self.assertEqual(handle.readlines(), ['bar']) # call repeatedly to check that a StopIteration is not propagated self.assertEqual(handle.readline(), 'bar') self.assertEqual(handle.readline(), 'bar') if __name__ == '__main__': unittest.main()