""" End-to-end tests. """ from __future__ import absolute_import, division, print_function import pickle import pytest import six from hypothesis import given from hypothesis.strategies import booleans import attr from attr._compat import TYPE from attr._make import NOTHING, Attribute from attr.exceptions import FrozenInstanceError @attr.s class C1(object): x = attr.ib(validator=attr.validators.instance_of(int)) y = attr.ib() @attr.s(slots=True) class C1Slots(object): x = attr.ib(validator=attr.validators.instance_of(int)) y = attr.ib() foo = None @attr.s() class C2(object): x = attr.ib(default=foo) y = attr.ib(default=attr.Factory(list)) @attr.s(slots=True) class C2Slots(object): x = attr.ib(default=foo) y = attr.ib(default=attr.Factory(list)) @attr.s class Super(object): x = attr.ib() def meth(self): return self.x @attr.s(slots=True) class SuperSlots(object): x = attr.ib() def meth(self): return self.x @attr.s class Sub(Super): y = attr.ib() @attr.s(slots=True) class SubSlots(SuperSlots): y = attr.ib() @attr.s(frozen=True, slots=True) class Frozen(object): x = attr.ib() @attr.s class SubFrozen(Frozen): y = attr.ib() @attr.s(frozen=True, slots=False) class FrozenNoSlots(object): x = attr.ib() class Meta(type): pass @attr.s @six.add_metaclass(Meta) class WithMeta(object): pass @attr.s(slots=True) @six.add_metaclass(Meta) class WithMetaSlots(object): pass FromMakeClass = attr.make_class("FromMakeClass", ["x"]) class TestDarkMagic(object): """ Integration tests. """ @pytest.mark.parametrize("cls", [C2, C2Slots]) def test_fields(self, cls): """ `attr.fields` works. """ assert ( Attribute(name="x", default=foo, validator=None, repr=True, cmp=True, hash=None, init=True), Attribute(name="y", default=attr.Factory(list), validator=None, repr=True, cmp=True, hash=None, init=True), ) == attr.fields(cls) @pytest.mark.parametrize("cls", [C1, C1Slots]) def test_asdict(self, cls): """ `attr.asdict` works. """ assert { "x": 1, "y": 2, } == attr.asdict(cls(x=1, y=2)) @pytest.mark.parametrize("cls", [C1, C1Slots]) def test_validator(self, cls): """ `instance_of` raises `TypeError` on type mismatch. """ with pytest.raises(TypeError) as e: cls("1", 2) # Using C1 explicitly, since slot classes don't support this. assert ( "'x' must be <{type} 'int'> (got '1' that is a <{type} " "'str'>).".format(type=TYPE), attr.fields(C1).x, int, "1", ) == e.value.args @given(booleans()) def test_renaming(self, slots): """ Private members are renamed but only in `__init__`. """ @attr.s(slots=slots) class C3(object): _x = attr.ib() assert "C3(_x=1)" == repr(C3(x=1)) @given(booleans(), booleans()) def test_programmatic(self, slots, frozen): """ `attr.make_class` works. """ PC = attr.make_class("PC", ["a", "b"], slots=slots, frozen=frozen) assert ( Attribute(name="a", default=NOTHING, validator=None, repr=True, cmp=True, hash=None, init=True), Attribute(name="b", default=NOTHING, validator=None, repr=True, cmp=True, hash=None, init=True), ) == attr.fields(PC) @pytest.mark.parametrize("cls", [Sub, SubSlots]) def test_subclassing_with_extra_attrs(self, cls): """ Sub-classing (where the subclass has extra attrs) does what you'd hope for. """ obj = object() i = cls(x=obj, y=2) assert i.x is i.meth() is obj assert i.y == 2 if cls is Sub: assert "Sub(x={obj}, y=2)".format(obj=obj) == repr(i) else: assert "SubSlots(x={obj}, y=2)".format(obj=obj) == repr(i) @pytest.mark.parametrize("base", [Super, SuperSlots]) def test_subclass_without_extra_attrs(self, base): """ Sub-classing (where the subclass does not have extra attrs) still behaves the same as a subclass with extra attrs. """ class Sub2(base): pass obj = object() i = Sub2(x=obj) assert i.x is i.meth() is obj assert "Sub2(x={obj})".format(obj=obj) == repr(i) @pytest.mark.parametrize("frozen_class", [ Frozen, # has slots=True attr.make_class("FrozenToo", ["x"], slots=False, frozen=True), ]) def test_frozen_instance(self, frozen_class): """ Frozen instances can't be modified (easily). """ frozen = frozen_class(1) with pytest.raises(FrozenInstanceError) as e: frozen.x = 2 with pytest.raises(FrozenInstanceError) as e: del frozen.x assert e.value.args[0] == "can't set attribute" assert 1 == frozen.x @pytest.mark.parametrize("cls", [C1, C1Slots, C2, C2Slots, Super, SuperSlots, Sub, SubSlots, Frozen, FrozenNoSlots, FromMakeClass]) @pytest.mark.parametrize("protocol", range(2, pickle.HIGHEST_PROTOCOL + 1)) def test_pickle_attributes(self, cls, protocol): """ Pickling/un-pickling of Attribute instances works. """ for attribute in attr.fields(cls): assert attribute == pickle.loads(pickle.dumps(attribute, protocol)) @pytest.mark.parametrize("cls", [C1, C1Slots, C2, C2Slots, Super, SuperSlots, Sub, SubSlots, Frozen, FrozenNoSlots, FromMakeClass]) @pytest.mark.parametrize("protocol", range(2, pickle.HIGHEST_PROTOCOL + 1)) def test_pickle_object(self, cls, protocol): """ Pickle object serialization works on all kinds of attrs classes. """ if len(attr.fields(cls)) == 2: obj = cls(123, 456) else: obj = cls(123) assert repr(obj) == repr(pickle.loads(pickle.dumps(obj, protocol))) def test_subclassing_frozen_gives_frozen(self): """ The frozen-ness of classes is inherited. Subclasses of frozen classes are also frozen and can be instantiated. """ i = SubFrozen("foo", "bar") assert i.x == "foo" assert i.y == "bar" @pytest.mark.parametrize("cls", [WithMeta, WithMetaSlots]) def test_metaclass_preserved(self, cls): """ Metaclass data is preserved. """ assert Meta == type(cls) def test_default_decorator(self): """ Default decorator sets the default and the respective method gets called. """ @attr.s class C(object): x = attr.ib(default=1) y = attr.ib() @y.default def compute(self): return self.x + 1 assert C(1, 2) == C() @pytest.mark.parametrize("slots", [True, False]) @pytest.mark.parametrize("frozen", [True, False]) def test_attrib_overwrite(self, slots, frozen): """ Subclasses can overwrite attributes of their superclass. """ @attr.s(slots=slots, frozen=frozen) class SubOverwrite(Super): x = attr.ib(default=attr.Factory(list)) assert SubOverwrite([]) == SubOverwrite() def test_dict_patch_class(self): """ dict-classes are never replaced. """ class C(object): x = attr.ib() C_new = attr.s(C) assert C_new is C def test_hash_by_id(self): """ With dict classes, hashing by ID is active for hash=False even on Python 3. This is incorrect behavior but we have to retain it for backward compatibility. """ @attr.s(hash=False) class HashByIDBackwardCompat(object): x = attr.ib() assert ( hash(HashByIDBackwardCompat(1)) != hash(HashByIDBackwardCompat(1)) ) @attr.s(hash=False, cmp=False) class HashByID(object): x = attr.ib() assert hash(HashByID(1)) != hash(HashByID(1)) @attr.s(hash=True) class HashByValues(object): x = attr.ib() assert hash(HashByValues(1)) == hash(HashByValues(1)) def test_handles_different_defaults(self): """ Unhashable defaults + subclassing values work. """ @attr.s class Unhashable(object): pass @attr.s class C(object): x = attr.ib(default=Unhashable()) @attr.s class D(C): pass @pytest.mark.parametrize("slots", [True, False]) def test_hash_false_cmp_false(self, slots): """ hash=False and cmp=False make a class hashable by ID. """ @attr.s(hash=False, cmp=False, slots=slots) class C(object): pass assert hash(C()) != hash(C()) def test_overwrite_super(self): """ Super classes can overwrite each other and the attributes are added in the order they are defined. """ @attr.s class C(object): c = attr.ib(default=100) x = attr.ib(default=1) b = attr.ib(default=23) @attr.s class D(C): a = attr.ib(default=42) x = attr.ib(default=2) d = attr.ib(default=3.14) @attr.s class E(D): y = attr.ib(default=3) z = attr.ib(default=4) assert "E(c=100, b=23, a=42, x=2, d=3.14, y=3, z=4)" == repr(E()) @pytest.mark.parametrize("base_slots", [True, False]) @pytest.mark.parametrize("sub_slots", [True, False]) @pytest.mark.parametrize("base_frozen", [True, False]) @pytest.mark.parametrize("sub_frozen", [True, False]) @pytest.mark.parametrize("base_converter", [True, False]) @pytest.mark.parametrize("sub_converter", [True, False]) def test_frozen_slots_combo(self, base_slots, sub_slots, base_frozen, sub_frozen, base_converter, sub_converter): """ A class with a single attribute, inheriting from another class with a single attribute. """ @attr.s(frozen=base_frozen, slots=base_slots) class Base(object): a = attr.ib(converter=int if base_converter else None) @attr.s(frozen=sub_frozen, slots=sub_slots) class Sub(Base): b = attr.ib(converter=int if sub_converter else None) i = Sub("1", "2") assert i.a == (1 if base_converter else "1") assert i.b == (2 if sub_converter else "2") if base_frozen or sub_frozen: with pytest.raises(FrozenInstanceError): i.a = "2" with pytest.raises(FrozenInstanceError): i.b = "3"