from operator import getitem from testfixtures import ( Replacer, Replace, ShouldRaise, TempDirectory, replace, compare, not_there, replace_in_environ, replace_on_class, replace_in_module, ) from unittest import TestCase import os from testfixtures.mock import Mock from testfixtures.tests import sample1, sample3 from testfixtures.tests import sample2 from .sample1 import z, X from .sample3 import SOME_CONSTANT from ..compat import PY_313_PLUS from warnings import catch_warnings class TestReplace(TestCase): def test_function(self): def test_z(): return 'replacement z' compare(sample1.z(), 'original z') @replace('testfixtures.tests.sample1.z', test_z) def test_something(): compare(sample1.z(), 'replacement z') compare(sample1.z(), 'original z') test_something() compare(sample1.z(), 'original z') def test_class(self): OriginalX = sample1.X class ReplacementX(sample1.X): pass self.assertFalse(OriginalX is ReplacementX) self.assertTrue(isinstance(sample1.X(), OriginalX)) @replace('testfixtures.tests.sample1.X', ReplacementX) def test_something(): self.assertFalse(OriginalX is ReplacementX) self.assertTrue(isinstance(sample1.X(), ReplacementX)) self.assertFalse(OriginalX is ReplacementX) self.assertTrue(isinstance(sample1.X(), OriginalX)) test_something() self.assertFalse(OriginalX is ReplacementX) self.assertTrue(isinstance(sample1.X(), OriginalX)) def test_method(self): def test_y(self): return self compare(sample1.X().y(), 'original y') @replace('testfixtures.tests.sample1.X.y', test_y) def test_something(): self.assertTrue(isinstance(sample1.X().y(), sample1.X)) compare(sample1.X().y(), 'original y') test_something() compare(sample1.X().y(), 'original y') def test_class_method(self): def rMethod(cls): return (cls, 1) compare(sample1.X().aMethod(), sample1.X) @replace('testfixtures.tests.sample1.X.aMethod', rMethod) def test_something(r): compare(r, rMethod) compare(sample1.X().aMethod(), (sample1.X, 1)) compare(sample1.X().aMethod(), sample1.X) test_something() compare(sample1.X().aMethod(), sample1.X) def test_multiple_replace(self): def test_y(self): return 'test y' def test_z(): return 'test z' compare(sample1.z(), 'original z') compare(sample1.X().y(), 'original y') @replace('testfixtures.tests.sample1.z', test_z) @replace('testfixtures.tests.sample1.X.y', test_y) def test_something(passed_test_y, passed_test_z): compare(test_z, passed_test_z) compare(test_y, passed_test_y) compare(sample1.z(), 'test z') compare(sample1.X().y(), 'test y') compare(sample1.z(), 'original z') compare(sample1.X().y(), 'original y') test_something() compare(sample1.z(), 'original z') compare(sample1.X().y(), 'original y') def test_gotcha(self): # Just because you replace an object in one context, # doesn't meant that it's replaced in all contexts! def test_z(): return 'test z' compare(sample1.z(), 'original z') compare(sample2.z(), 'original z') @replace('testfixtures.tests.sample1.z', test_z) def test_something(): compare(sample1.z(), 'test z') compare(sample2.z(), 'original z') compare(sample1.z(), 'original z') compare(sample2.z(), 'original z') test_something() compare(sample1.z(), 'original z') compare(sample2.z(), 'original z') def test_raises(self): def test_z(): return 'replacement z' compare(sample1.z(), 'original z') @replace('testfixtures.tests.sample1.z', test_z) def test_something(): compare(sample1.z(), 'replacement z') raise Exception() compare(sample1.z(), 'original z') with ShouldRaise(): test_something() compare(sample1.z(), 'original z') def test_want_replacement(self): o = object() @replace('testfixtures.tests.sample1.z', o) def test_something(r): self.assertTrue(r is o) self.assertTrue(sample1.z is o) test_something() def test_not_there(self): o = object() @replace('testfixtures.tests.sample1.bad', o) def test_something(r): pass # pragma: no cover with ShouldRaise(AttributeError("Original 'bad' not found")): test_something() def test_not_there_ok(self): o = object() @replace('testfixtures.tests.sample1.bad', o, strict=False) def test_something(r): self.assertTrue(r is o) self.assertTrue(sample1.bad is o) test_something() def test_replace_dict(self): from testfixtures.tests.sample1 import some_dict original = some_dict['key'] replacement = object() @replace('testfixtures.tests.sample1.some_dict.key', replacement) def test_something(obj): self.assertTrue(obj is replacement) self.assertTrue(some_dict['key'] is replacement) test_something() self.assertTrue(some_dict['key'] is original) def test_replace_delattr(self): from testfixtures.tests import sample1 @replace('testfixtures.tests.sample1.some_dict', not_there) def test_something(obj): self.assertFalse(hasattr(sample1, 'some_dict')) test_something() self.assertEqual(sample1.some_dict, {'complex_key': [1, 2, 3], 'key': 'value'}) def test_replace_delattr_not_there(self): @replace('testfixtures.tests.sample1.foo', not_there) def test_something(obj): pass # pragma: no cover with ShouldRaise(AttributeError("Original 'foo' not found")): test_something() def test_replace_delattr_not_there_not_strict(self): from testfixtures.tests import sample1 @replace('testfixtures.tests.sample1.foo', not_there, strict=False) def test_something(obj): self.assertFalse(hasattr(sample1, 'foo')) test_something() def test_replace_delattr_not_there_restored(self): from testfixtures.tests import sample1 @replace('testfixtures.tests.sample1.foo', not_there, strict=False) def test_something(obj): sample1.foo = 'bar' test_something() self.assertFalse(hasattr(sample1, 'foo')) def test_replace_delattr_cant_remove(self): message = " has __dict__ but 'today' is not in it" with Replacer() as r: with ShouldRaise(AttributeError(message)): r.replace('datetime.datetime.today', not_there) def test_replace_delattr_cant_remove_not_strict(self): message = "cannot set 'today' attribute of immutable type 'datetime.datetime'" with Replacer() as r: with ShouldRaise(TypeError(message)): r.replace('datetime.datetime.today', not_there, strict=False) def test_replace_dict_remove_key(self): from testfixtures.tests.sample1 import some_dict @replace('testfixtures.tests.sample1.some_dict.key', not_there) def test_something(obj): self.assertFalse('key' in some_dict) test_something() self.assertEqual(sorted(some_dict.keys()), ['complex_key', 'key']) def test_replace_dict_remove_key_not_there(self): from testfixtures.tests.sample1 import some_dict @replace('testfixtures.tests.sample1.some_dict.badkey', not_there) def test_something(obj): self.assertFalse('badkey' in some_dict) # pragma: no cover with ShouldRaise(AttributeError("Original 'badkey' not found")): test_something() self.assertEqual(sorted(some_dict.keys()), ['complex_key', 'key']) def test_replace_dict_remove_key_not_there_not_strict(self): from testfixtures.tests.sample1 import some_dict @replace('testfixtures.tests.sample1.some_dict.badkey', not_there, strict=False) def test_something(obj): self.assertFalse('badkey' in some_dict) test_something() self.assertEqual(sorted(some_dict.keys()), ['complex_key', 'key']) def test_replace_dict_ensure_key_not_there_restored(self): from testfixtures.tests.sample1 import some_dict @replace('testfixtures.tests.sample1.some_dict.badkey', not_there, strict=False) def test_something(obj): some_dict['badkey'] = 'some test value' test_something() self.assertEqual(sorted(some_dict.keys()), ['complex_key', 'key']) def test_replace_dict_not_there(self): from testfixtures.tests.sample1 import some_dict replacement = object() @replace('testfixtures.tests.sample1.some_dict.key2', replacement, strict=False) def test_something(obj): self.assertTrue(obj is replacement) self.assertTrue(some_dict['key2'] is replacement) test_something() self.assertEqual(sorted(some_dict.keys()), ['complex_key', 'key']) def test_replace_dict_not_there_empty_string(self): from testfixtures.tests.sample1 import some_dict @replace('testfixtures.tests.sample1.some_dict.key2', '', strict=False) def test_something(): self.assertEqual(some_dict['key2'], '') test_something() self.assertEqual(sorted(some_dict.keys()), ['complex_key', 'key']) def test_replace_complex(self): from testfixtures.tests.sample1 import some_dict original = some_dict['complex_key'][1] replacement = object() @replace('testfixtures.tests.sample1.some_dict.complex_key.1', replacement) def test_something(obj): self.assertTrue(obj is replacement) self.assertEqual(some_dict['complex_key'], [1, obj, 3]) test_something() self.assertEqual(some_dict['complex_key'], [1, 2, 3]) self.assertTrue(original is some_dict['complex_key'][1]) def test_replacer_del(self): r = Replacer() r.replace('testfixtures.tests.sample1.left_behind', object(), strict=False) with catch_warnings(record=True) as w: del r self.assertTrue(len(w), 1) compare(str(w[0].message), "Replacer deleted without being restored, originals left:" " {'testfixtures.tests.sample1.left_behind': >}") def test_multiple_replaces(self): orig = os.path.sep with Replacer() as r: r.replace('os.path.sep', '$') compare(os.path.sep, '$') r.replace('os.path.sep', '=') compare(os.path.sep, '=') compare(orig, os.path.sep) def test_sub_module_import(self): with TempDirectory() as dir: dir.write('module/__init__.py', b'') dir.write('module/submodule.py', b'def foo(): return "foo"') with Replacer() as r: r.replace('sys.path', [dir.path]) def bar(): return "bar" # now test r.replace('module.submodule.foo', bar) from module.submodule import foo # type: ignore[import-not-found] compare(foo(), "bar") def test_staticmethod(self): compare(sample1.X.bMethod(), 2) with Replacer() as r: r.replace('testfixtures.tests.sample1.X.bMethod', lambda: 1) compare(sample1.X.bMethod(), 1) compare(sample1.X.bMethod(), 2) def test_use_as_cleanup(self): def test_z(): return 'replacement z' compare(sample1.z(), 'original z') replace = Replacer() compare(sample1.z(), 'original z') replace('testfixtures.tests.sample1.z', test_z) cleanup = replace.restore try: compare(sample1.z(), 'replacement z') finally: cleanup() compare(sample1.z(), 'original z') def test_replace_context_manager(self): def test_z(): return 'replacement z' compare(sample1.z(), 'original z') with Replace('testfixtures.tests.sample1.z', test_z) as z: compare(z(), 'replacement z') compare(sample1.z(), 'replacement z') compare(sample1.z(), 'original z') def test_multiple_context_managers(self): def test_y(self): return 'test y' def test_z(): return 'test z' compare(sample1.z(), 'original z') compare(sample1.X().y(), 'original y') with Replacer() as replace: z = replace('testfixtures.tests.sample1.z', test_z) y = replace('testfixtures.tests.sample1.X.y', test_y) compare(z(), 'test z') compare(y, sample1.X.y) compare(sample1.X().y(), 'test y') compare(sample1.z(), 'test z') compare(sample1.X().y(), 'test y') compare(sample1.z(), 'original z') compare(sample1.X().y(), 'original y') def test_context_manager_not_strict(self): def test_z(): return 'replacement z' with Replace('testfixtures.tests.sample1.foo', test_z, strict=False): compare(sample1.foo(), 'replacement z') def test_context_manager_full_spec(self): my_dict = {} with Replace(my_dict, name='foo', accessor=getitem, replacement=42, strict=False): compare(my_dict, expected={'foo': 42}) compare(my_dict, expected={}) def test_decorator_full_spec(self): my_dict = {} @replace(my_dict, name='foo', accessor=getitem, replacement=42, strict=False) def test_something(): compare(my_dict, expected={'foo': 42}) test_something() compare(my_dict, expected={}) def test_replace_method_full_spec(self): my_dict = {} with Replacer() as r: r.replace(my_dict, name='foo', accessor=getitem, replacement=42, strict=False) compare(my_dict, expected={'foo': 42}) compare(my_dict, expected={}) def test_context_manager_specified_method(self): class SampleClass: def method(self, x): return x*2 sample_obj = SampleClass() with Replace(SampleClass.method, lambda self, x: x*3, container=SampleClass, name='method', accessor=getattr): compare(sample_obj.method(1), expected=3) compare(sample_obj.method(1), expected=2) def test_decorator_specified_method(self): class SampleClass: def method(self, x): return x*2 sample_obj = SampleClass() @replace(SampleClass.method, lambda self, x: x*3, container=SampleClass, name='method', accessor=getattr) def test_something(): compare(sample_obj.method(1), expected=3) test_something() compare(sample_obj.method(1), expected=2) def test_fully_specified_method(self): class SampleClass: def method(self, x): return x*2 sample_obj = SampleClass() with Replacer() as r: r.replace(SampleClass.method, lambda self, x: x*3, container=SampleClass, name='method', accessor=getattr) compare(sample_obj.method(1), expected=3) compare(sample_obj.method(1), expected=2) def test_fully_specified_method_incorrect_name(self): class SampleClass: def a(self): return 1 def b(self): return 2 sample_obj = SampleClass() s_repr = repr(SampleClass) a_repr = repr(SampleClass.a) b_repr = repr(SampleClass.b) replacer = Replacer() with ShouldRaise(AssertionError( f" of 'b' from {s_repr} gave {b_repr}, expected {a_repr}" )): replacer(SampleClass.a, lambda self: 3, container=SampleClass, name='b', accessor=getattr) compare(sample_obj.a(), expected=1) compare(sample_obj.b(), expected=2) def test_traverse_from_container(self): x = sample1.X() with Replace('.X.aMethod', lambda cls: 'FOO', container=sample1): compare(x.aMethod(), expected='FOO') assert x.aMethod() is sample1.X def test_only_relative_traverse_from_container(self): x = sample1.X() replacer = Replacer() with ShouldRaise(AssertionError('Absolute traversal not allowed when container supplied')): replacer('foo', object(), container=sample1) def test_no_name_and_target_string(self): x = sample1.X() replacer = Replacer() with ShouldRaise(AttributeError("Original 'aMethod' not found")): replacer('.X', lambda cls: 'FOO', name='aMethod', container=sample1) assert x.aMethod() is sample1.X def test_no_accessor_allowed_when_name_not_specified(self): my_dict = {} replacer = Replacer() with ShouldRaise(TypeError('accessor is not used unless name is specified')): replacer(container=my_dict, target='.my.key', accessor=getitem, replacement='bar') compare(my_dict, expected={}) def test_dict_and_name(self): my_dict = {} with Replace(my_dict, name='foo', replacement=42, strict=False): compare(my_dict, expected={'foo': 42}) compare(my_dict, expected={}) def test_name_and_dict(self): environ = {} with Replace('.MY_ENV_VAR', 'True', container=environ, strict=False): compare(environ, expected={'MY_ENV_VAR': 'True'}) compare(environ, expected={}) def test_non_string_target_and_no_name(self): my_dict = {} replacer = Replacer() with ShouldRaise(TypeError('name must be specified when target is not a string')): replacer(my_dict, replacement=42, strict=False) compare(my_dict, expected={}) def test_method_on_instance(self): class SampleClass: def method(self, x): return x*2 sample = SampleClass() with Replacer() as replace: replace(sample.method, lambda x: x * 3, container=sample, strict=False) compare(sample.method(1), expected=3) compare(sample.method(1), expected=2) def test_class_attribute(self): mock = Mock() mock.FOO = set() class SampleClass: FOO = mock.FOO sample = SampleClass() with Replace(SampleClass.FOO, {'X'}, container=SampleClass, name='FOO'): compare(sample.FOO, expected={'X'}) compare(mock.FOO, expected=set()) compare(sample.FOO, expected=set()) def test_function_and_module(self): with Replace(z, lambda: 'all new z', container=sample1): from .sample1 import z as sample1_z from .sample3 import z as sample3_z compare(sample1_z(), expected='all new z') compare(sample3_z(), expected='original z') def test_constant(self): with Replace(SOME_CONSTANT, 43, container=sample3, name='SOME_CONSTANT'): from .sample3 import SOME_CONSTANT as sample3_some_constant compare(sample3_some_constant, expected=43) def test_relative_nested_but_not_present(self): nested = {'b': [1, 2, 3]} with Replacer() as r: with ShouldRaise(AttributeError("Original 'a' not found")): r(container=nested, target='.a.1', replacement=42) def test_alternative_separator(self): nested = {'.b': 1, 'c.d': 2, 'e': {'f': 42}} with Replacer() as r: r(container=nested, target=':.b', replacement=3, sep=':') r(container=nested, target=':c.d', replacement=4, sep=':') compare(nested, expected={'.b': 3, 'c.d': 4, 'e': {'f': 42}}) with Replace(container=nested, target=':e:f', replacement=43, sep=':'): compare(nested, expected={'.b': 1, 'c.d': 2, 'e': {'f': 43}}) @replace(container=nested, target=':e:f', replacement=43, sep=':') def function(): compare(nested, expected={'.b': 1, 'c.d': 2, 'e': {'f': 43}}) function() def test_alternative_separator_traversal_not_valid(self): nested = {'.b': 1} with Replacer() as r: with ShouldRaise(AttributeError("Original '.a.1' not found")): r(container=nested, target=':.a.1', replacement=3, sep=':') class TestEnviron: def test_key_present(self): os.environ['TESTFIXTURES_SAMPLE_KEY_PRESENT'] = 'ORIGINAL' with Replacer() as replace: replace.in_environ('TESTFIXTURES_SAMPLE_KEY_PRESENT', 'NEW') compare(os.environ['TESTFIXTURES_SAMPLE_KEY_PRESENT'], expected='NEW') compare(os.environ['TESTFIXTURES_SAMPLE_KEY_PRESENT'], expected='ORIGINAL') def test_key_not_present(self): assert 'TESTFIXTURES_SAMPLE_KEY_MISSING' not in os.environ with Replacer() as replace: replace.in_environ('TESTFIXTURES_SAMPLE_KEY_MISSING', 'NEW') compare(os.environ['TESTFIXTURES_SAMPLE_KEY_MISSING'], expected='NEW') assert 'TESTFIXTURES_SAMPLE_KEY_MISSING' not in os.environ def test_non_string_replacement(self): with Replacer() as replace: replace.in_environ('PORT', 1) compare(os.environ['PORT'], expected='1') def test_ensure_not_present(self): os.environ['TESTFIXTURES_SAMPLE_KEY_PRESENT'] = 'ORIGINAL' with Replacer() as replace: replace.in_environ('TESTFIXTURES_SAMPLE_KEY_PRESENT', not_there) assert 'TESTFIXTURES_SAMPLE_KEY_PRESENT' not in os.environ class TestOnClass: def test_method_on_class(self): class SampleClass: def method(self, x): return x*2 original = SampleClass.__dict__['method'] sample = SampleClass() with Replacer() as replace: replace.on_class(SampleClass.method, lambda self, x: x*3) compare(sample.method(1), expected=3) compare(sample.method(1), expected=2) assert SampleClass.__dict__['method'] is original def test_method_on_subclass(self): class SampleClass: def method_a(self, x): return x*2 class SampleSubClass(SampleClass): """ Some doc! """ def method_b(self, x): return x*3 original_a = SampleClass.__dict__['method_a'] original_b = SampleSubClass.__dict__['method_b'] sample = SampleSubClass() with Replacer() as replace: replace.on_class(SampleSubClass.method_a, lambda self, x: x*4) replace.on_class(SampleSubClass.method_b, lambda self, x: x*5) compare(sample.method_a(1), expected=4) compare(sample.method_b(1), expected=5) compare(sample.method_a(1), expected=2) compare(sample.method_b(1), expected=3) assert SampleClass.__dict__['method_a'] is original_a assert SampleSubClass.__dict__['method_b'] is original_b assert 'method_a' not in SampleSubClass.__dict__ def test_attributes_on_class(self): class SampleClass: x = 1 y = 'a' sample = SampleClass() with Replacer() as replace: # without names, we get a useful errors: with ShouldRaise(TypeError("attribute named 'x' must be a method")): replace.on_class(SampleClass.x, 2, name='x') with ShouldRaise(TypeError("attribute must be a method")): replace.on_class(SampleClass.y, 'b') # okay, so we'll use the full form: replace(SampleClass.x, 2, container=SampleClass, name='x') replace(SampleClass.y, 'b', container=SampleClass, name='y') compare(sample.x, expected=2) compare(sample.y, expected='b') compare(sample.x, expected=1) compare(sample.y, expected='a') def test_method_on_instance(self): class SampleClass: def method(self, x): return x*2 original = SampleClass.__dict__['method'] sample = SampleClass() with Replacer() as replace: with ShouldRaise(AttributeError): replace.on_class(sample.method, lambda self, x: x*3) # ...so use explicit and non-strict: replace(sample.method, lambda x: x * 3, container=sample, strict=False) compare(sample.method(1), expected=3) compare(sample.method(1), expected=2) assert SampleClass.__dict__['method'] is original def test_badly_decorated_method(self): def bad(f): def inner(self, x): return f(self, x) return inner class SampleClass: @bad def method(self, x): return x*2 original = SampleClass.__dict__['method'] sample = SampleClass() with Replacer() as replace: # without the name, we get a useful error: with ShouldRaise(AttributeError( f"could not find container of {SampleClass.method} using name 'inner'" )): replace.on_class(SampleClass.method, lambda self_, x: x*3) assert SampleClass.__dict__['method'] is original replace.on_class(SampleClass.method, lambda self_, x: x*3, name='method') compare(sample.method(1), expected=3) compare(sample.method(1), expected=2) assert SampleClass.__dict__['method'] is original def test_classmethod(self): class SampleClass: @classmethod def method(cls, x): return x*2 original = SampleClass.__dict__['method'] with Replacer() as replace: replace.on_class(SampleClass.method, classmethod(lambda cls, x: x*3)) compare(SampleClass.method(1), expected=3) compare(SampleClass.method(1), expected=2) assert SampleClass.__dict__['method'] is original def test_staticmethod(self): class SampleClass: @staticmethod def method(x): return x*2 original = SampleClass.__dict__['method'] with Replacer() as replace: replace.on_class(SampleClass.method, lambda x: x*3) compare(SampleClass.method(1), expected=3) compare(SampleClass.method(1), expected=2) assert SampleClass.__dict__['method'] is original def test_method_on_class_in_module(self): sample = X() original = X.__dict__['y'] with Replacer() as replace: replace.on_class(X.y, lambda self_: 'replacement y') compare(sample.y(), expected='replacement y') compare(sample.y(), expected='original y') assert X.__dict__['y'] is original def test_method_on_instance_in_module(self): sample = X() original = X.__dict__['y'] with Replacer() as replace: replace(sample.y, lambda: 'replacement y', container=sample, strict=False) compare(sample.y(), expected='replacement y') compare(sample.y(), expected='original y') assert X.__dict__['y'] is original def test_classmethod_on_class_in_module(self): original = X.__dict__['aMethod'] with Replacer() as replace: replace.on_class(X.aMethod, classmethod(lambda cls: (cls, cls))) compare(X.aMethod(), expected=(X, X)) compare(X.aMethod(), expected=X) assert X.__dict__['aMethod'] is original def test_classmethod_on_instance_in_module(self): sample = X() original = X.__dict__['aMethod'] with Replacer() as replace: replace.on_class(sample.aMethod, classmethod(lambda cls: (cls, cls))) compare(sample.aMethod(), expected=(X, X)) compare(sample.aMethod(), expected=X) assert X.__dict__['aMethod'] is original def test_staticmethod_on_class_in_module(self): original = X.__dict__['bMethod'] with Replacer() as replace: replace.on_class(X.bMethod, lambda: 3) compare(X.bMethod(), expected=3) compare(X.bMethod(), expected=2) assert X.__dict__['bMethod'] is original def test_staticmethod_on_instance_in_module(self): original = X.__dict__['bMethod'] sample = X() with Replacer() as replace: replace(sample.bMethod, lambda: 3, container=sample, strict=False) compare(sample.bMethod(), expected=3) compare(X.bMethod(), expected=2) assert X.__dict__['bMethod'] is original def test_multiple_methods_on_class(self): original_y = X.y original_a_result = X.aMethod() with Replacer() as replace: # y = replace('testfixtures.tests.sample1.X.y', Mock()) # y.return_value = 'mock y' # aMethod = replace('testfixtures.tests.sample1.X.aMethod', Mock()) # aMethod.return_value = 'mock method' replace.on_class(X.y, lambda self: 'mock y') replace.on_class(X.aMethod, lambda cls: 'mock method') x = X() compare(x.y(), expected='mock y') compare(x.aMethod(), expected='mock method') assert X.y is original_y assert X.aMethod() is original_a_result class TestInModule: def test_function_guess_module(self): with Replacer() as replace: replace.in_module(z, lambda: 'all new z') from .sample1 import z as sample1_z from .sample3 import z as sample3_z compare(sample1_z(), expected='all new z') compare(sample3_z(), expected='original z') from .sample1 import z as sample1_z from .sample3 import z as sample3_z compare(sample1_z(), expected='original z') compare(sample3_z(), expected='original z') def test_function_explict_module(self): with Replacer() as replace: replace.in_module(z, lambda: 'all new z', module=sample3) from .sample1 import z as sample1_z from .sample3 import z as sample3_z compare(sample1_z(), expected='original z') compare(sample3_z(), expected='all new z') from .sample1 import z as sample1_z from .sample3 import z as sample3_z compare(sample1_z(), expected='original z') compare(sample3_z(), expected='original z') def test_constant(self): replace = Replacer() with ShouldRaise(AttributeError("'int' object has no attribute '__module__'")): replace.in_module(SOME_CONSTANT, 43) from .sample3 import SOME_CONSTANT as sample3_some_constant compare(sample3_some_constant, expected=42) class TestConvenience: def test_environ(self): os.environ['TESTFIXTURES_SAMPLE_KEY_PRESENT'] = 'ORIGINAL' with replace_in_environ('TESTFIXTURES_SAMPLE_KEY_PRESENT', 'NEW'): compare(os.environ['TESTFIXTURES_SAMPLE_KEY_PRESENT'], expected='NEW') compare(os.environ['TESTFIXTURES_SAMPLE_KEY_PRESENT'], expected='ORIGINAL') def test_on_class(self): class SampleClass: def method(self, x): return x*2 sample = SampleClass() with replace_on_class(SampleClass.method, lambda self, x: x*3, name='method'): compare(sample.method(1), expected=3) compare(sample.method(1), expected=2) def test_in_module(self): with replace_in_module(z, lambda: 'all new z', module=sample3): from .sample1 import z as sample1_z from .sample3 import z as sample3_z compare(sample1_z(), expected='original z') compare(sample3_z(), expected='all new z') from .sample1 import z as sample1_z from .sample3 import z as sample3_z compare(sample1_z(), expected='original z') compare(sample3_z(), expected='original z') class OriginA: bar = 13 def __init__(self): self.foo = 43 def method(self, x): return x * 2 original = method class UseB(OriginA): pass class UseC(OriginA): pass class OriginD: def __init__(self, attrs): self.attrs = attrs def __getattr__(self, item): return self.attrs[item] class OriginE: __slots__ = 'attr', def method(self, x): return x * 2 original = method class UseF(OriginE): __slots__ = 'attr', class UseG(OriginE): __slots__ = 'attr', def check_originals_not_modified(): assert OriginA.__dict__['method'] is OriginA.original assert OriginA.__dict__['bar'] == 13 assert 'method' not in UseB.__dict__ assert 'method' not in UseC.__dict__ assert OriginE.method is OriginE.original def check_behaviour_is_unchanged(*callables): for c in callables: compare(c(1), expected=2, prefix=repr(c)) class TestReplaceWithInterestingOriginsStrict: strict = True def test_class_attribute_on_class(self): sample_a = OriginA() sample_b = UseB() sample_c = UseC() with Replace(OriginA.bar, name='bar', replacement=31, strict=self.strict, container=OriginA): compare(sample_a.bar, expected=31) compare(sample_b.bar, expected=31) compare(sample_c.bar, expected=31) compare(sample_a.bar, expected=13) compare(sample_b.bar, expected=13) compare(sample_c.bar, expected=13) check_originals_not_modified() def test_class_attribute_on_subclass(self): sample_a = OriginA() sample_b = UseB() sample_c = UseC() replace_ = Replacer() with ShouldRaise(AttributeError(f"{UseB!r} has __dict__ but 'bar' is not in it")): replace_(UseB.bar, name='bar', replacement=31, strict=self.strict, container=UseB) compare(sample_a.bar, expected=13) compare(sample_b.bar, expected=13) compare(sample_c.bar, expected=13) check_originals_not_modified() def test_method_on_subclass(self): sample_a = OriginA() sample_b = UseB() sample_c = UseC() replace_ = Replacer() with ShouldRaise(AttributeError(f"{UseB!r} has __dict__ but 'method' is not in it")): replace_( UseB.method, lambda self_, x: x*4, name='method', container=UseB, strict=self.strict ) check_behaviour_is_unchanged(sample_a.method, sample_b.method, sample_c.method) check_originals_not_modified() def test_class_attribute_on_instance_of_class(self): obj = OriginA() bar = obj.bar replace_ = Replacer() with ShouldRaise(AttributeError(f"{obj!r} has __dict__ but 'bar' is not in it")): replace_(obj, name='bar', replacement=31, strict=self.strict) compare(obj.bar, expected=13) assert obj.bar is bar def test_instance_attribute_on_instance_of_class(self): obj = OriginA() foo = obj.foo with Replace(obj, name='foo', replacement=42, strict=self.strict): compare(obj.foo, expected=42) assert obj.foo is foo def test_method_on_instance_of_class(self): sample_a = OriginA() sample_b = UseB() sample_c = UseC() replace = Replacer() with ShouldRaise(TypeError( "Cannot replace methods on instances with strict=True, " "replace on class or use strict=False") ): replace( sample_a.method, lambda self_, x: x*4, name='method', container=sample_a, strict=self.strict ) check_behaviour_is_unchanged(sample_a.method, sample_b.method, sample_c.method) check_originals_not_modified() def test_method_on_instance_of_subclass(self): obj = UseB() replace = Replacer() with ShouldRaise(TypeError( "Cannot replace methods on instances with strict=True, " "replace on class or use strict=False") ): replace( obj.method, lambda self_, x: x*4, name='method', container=obj, strict=self.strict ) check_behaviour_is_unchanged(obj.method) check_originals_not_modified() def test_valid_attribute_on_instance_of_slotted_class(self): obj = OriginE() assert not hasattr(obj, '__dict__') obj.attr = 41 with Replace(obj, name='attr', replacement=42, strict=self.strict): compare(obj.attr, expected=42) assert obj.attr == 41 def test_invalid_attribute_on_instance_of_slotted_class(self): obj = OriginE() assert not hasattr(obj, '__dict__') replace_ = Replacer() with ShouldRaise(AttributeError("Original 'bad' not found")): replace_(obj, name='bad', replacement=42, strict=self.strict) def test_method_on_instance_of_slotted_subclass(self): sample_e = OriginE() sample_f = UseF() sample_g = UseG() obj = UseF() assert not hasattr(obj, '__dict__') replace_ = Replacer() with ShouldRaise(TypeError( "Cannot replace methods on instances with strict=True, " "replace on class or use strict=False" )): replace_( obj.method, lambda self_, x: x*4, name='method', container=obj, strict=self.strict ) check_behaviour_is_unchanged(sample_e.method, sample_f.method, sample_g.method) check_behaviour_is_unchanged() def test_interesting_container(self): replace_ = Replacer() sample = OriginD({'foo': 'bar'}) with ShouldRaise(AttributeError(f"{sample!r} has __dict__ but 'foo' is not in it")): replace_(sample.foo, 'baz', name='foo', container=sample, strict=self.strict) compare(sample.foo, expected='bar') assert 'foo' not in sample.__dict__ def test_mock_and_name(self): my_obj = Mock() foo = my_obj.foo # Mock instances are tricky in that they have a __dict__ but # their attributes are not in it: replace_ = Replacer() with ShouldRaise(AttributeError(f"{my_obj!r} has __dict__ but 'foo' is not in it")): replace_(my_obj, name='foo', replacement=42, strict=self.strict) assert my_obj.foo is foo class TestReplaceWithInterestingOriginsNotStrict(TestReplaceWithInterestingOriginsStrict): # This subclasses TestReplaceWithInterestingOriginsStrict to ensure we check all the same cases strict = False def test_class_attribute_on_subclass(self): sample_a = OriginA() sample_b = UseB() sample_c = UseC() with Replace(UseB.bar, name='bar', replacement=31, strict=self.strict, container=UseB): compare(sample_a.bar, expected=13) compare(sample_b.bar, expected=31) compare(sample_c.bar, expected=13) compare(sample_a.bar, expected=13) compare(sample_b.bar, expected=13) compare(sample_c.bar, expected=13) check_originals_not_modified() def test_method_on_subclass(self): sample_a = OriginA() sample_b = UseB() sample_c = UseC() with Replace( UseB.method, lambda self_, x: x*4, name='method', container=UseB, strict=self.strict ): compare(sample_b.method(1), expected=4) check_behaviour_is_unchanged(sample_a.method, sample_c.method) check_behaviour_is_unchanged(sample_a.method, sample_b.method, sample_c.method) check_originals_not_modified() def test_class_attribute_on_instance_of_class(self): obj = OriginA() bar = obj.bar with Replace(obj, name='bar', replacement=31, strict=self.strict): compare(obj.bar, expected=31) assert obj.bar is bar def test_instance_attribute_on_instance_of_class(self): obj = OriginA() foo = obj.foo with Replace(obj, name='foo', replacement=42, strict=self.strict): compare(obj.foo, expected=42) assert obj.foo is foo def test_method_on_instance_of_class(self): sample_a = OriginA() sample_b = UseB() sample_c = UseC() with Replace( sample_a.method, lambda x: x*4, name='method', container=sample_a, strict=self.strict ): compare(sample_a.method(1), expected=4) check_behaviour_is_unchanged(sample_b.method, sample_c.method) check_behaviour_is_unchanged(sample_a.method, sample_b.method, sample_c.method) check_originals_not_modified() def test_method_on_instance_of_subclass(self): sample_a = OriginA() sample_b = UseB() sample_c = UseC() with Replace( sample_b.method, lambda x: x*4, name='method', container=sample_b, strict=self.strict ): compare(sample_b.method(1), expected=4) check_behaviour_is_unchanged(sample_a.method, sample_c.method) check_behaviour_is_unchanged(sample_a.method, sample_b.method, sample_c.method) check_originals_not_modified() def test_invalid_attribute_on_instance_of_slotted_class(self): obj = OriginE() assert not hasattr(obj, '__dict__') replace_ = Replacer() message = "'OriginE' object has no attribute 'bad'" if PY_313_PLUS: message += " and no __dict__ for setting new attributes" with ShouldRaise(AttributeError(message)): replace_(obj, name='bad', replacement=42, strict=self.strict) def test_method_on_instance_of_slotted_subclass(self): sample_e = OriginE() sample_f = UseF() sample_g = UseG() obj = UseF() assert not hasattr(obj, '__dict__') replace_ = Replacer() with ShouldRaise(AttributeError("'UseF' object attribute 'method' is read-only")): replace_( obj.method, lambda self_, x: x*4, name='method', container=obj, strict=self.strict ) check_behaviour_is_unchanged(sample_e.method, sample_f.method, sample_g.method) check_behaviour_is_unchanged() def test_interesting_container(self): sample = OriginD({'foo': 'bar'}) with Replace(sample.foo, 'baz', name='foo', container=sample, strict=self.strict): compare(sample.foo, expected='baz') compare(sample.foo, expected='bar') assert 'foo' not in sample.__dict__ def test_mock_and_name(self): my_obj = Mock() foo = my_obj.foo assert hasattr(my_obj, 'foo') assert getattr(my_obj, 'foo', None) with Replace(my_obj, name='foo', replacement=42, strict=self.strict): compare(my_obj.foo, expected=42) with ShouldRaise(AttributeError('foo')): # Mock instances are tricky in that they have a __dict__ but # their attributes are not in it, confusing Replace, which deletes # the attribute on restore as a result: assert my_obj.foo is foo