from __future__ import annotations from mypy.nodes import CONTRAVARIANT, COVARIANT, INVARIANT from mypy.subtypes import is_subtype from mypy.test.helpers import Suite from mypy.test.typefixture import InterfaceTypeFixture, TypeFixture from mypy.types import Instance, TupleType, Type, UninhabitedType, UnpackType class SubtypingSuite(Suite): def setUp(self) -> None: self.fx = TypeFixture(INVARIANT) self.fx_contra = TypeFixture(CONTRAVARIANT) self.fx_co = TypeFixture(COVARIANT) def test_trivial_cases(self) -> None: for simple in self.fx_co.a, self.fx_co.o, self.fx_co.b: self.assert_subtype(simple, simple) def test_instance_subtyping(self) -> None: self.assert_strict_subtype(self.fx.a, self.fx.o) self.assert_strict_subtype(self.fx.b, self.fx.o) self.assert_strict_subtype(self.fx.b, self.fx.a) self.assert_not_subtype(self.fx.a, self.fx.d) self.assert_not_subtype(self.fx.b, self.fx.c) def test_simple_generic_instance_subtyping_invariant(self) -> None: self.assert_subtype(self.fx.ga, self.fx.ga) self.assert_subtype(self.fx.hab, self.fx.hab) self.assert_not_subtype(self.fx.ga, self.fx.g2a) self.assert_not_subtype(self.fx.ga, self.fx.gb) self.assert_not_subtype(self.fx.gb, self.fx.ga) def test_simple_generic_instance_subtyping_covariant(self) -> None: self.assert_subtype(self.fx_co.ga, self.fx_co.ga) self.assert_subtype(self.fx_co.hab, self.fx_co.hab) self.assert_not_subtype(self.fx_co.ga, self.fx_co.g2a) self.assert_not_subtype(self.fx_co.ga, self.fx_co.gb) self.assert_subtype(self.fx_co.gb, self.fx_co.ga) def test_simple_generic_instance_subtyping_contravariant(self) -> None: self.assert_subtype(self.fx_contra.ga, self.fx_contra.ga) self.assert_subtype(self.fx_contra.hab, self.fx_contra.hab) self.assert_not_subtype(self.fx_contra.ga, self.fx_contra.g2a) self.assert_subtype(self.fx_contra.ga, self.fx_contra.gb) self.assert_not_subtype(self.fx_contra.gb, self.fx_contra.ga) def test_generic_subtyping_with_inheritance_invariant(self) -> None: self.assert_subtype(self.fx.gsab, self.fx.gb) self.assert_not_subtype(self.fx.gsab, self.fx.ga) self.assert_not_subtype(self.fx.gsaa, self.fx.gb) def test_generic_subtyping_with_inheritance_covariant(self) -> None: self.assert_subtype(self.fx_co.gsab, self.fx_co.gb) self.assert_subtype(self.fx_co.gsab, self.fx_co.ga) self.assert_not_subtype(self.fx_co.gsaa, self.fx_co.gb) def test_generic_subtyping_with_inheritance_contravariant(self) -> None: self.assert_subtype(self.fx_contra.gsab, self.fx_contra.gb) self.assert_not_subtype(self.fx_contra.gsab, self.fx_contra.ga) self.assert_subtype(self.fx_contra.gsaa, self.fx_contra.gb) def test_interface_subtyping(self) -> None: self.assert_subtype(self.fx.e, self.fx.f) self.assert_equivalent(self.fx.f, self.fx.f) self.assert_not_subtype(self.fx.a, self.fx.f) def test_generic_interface_subtyping(self) -> None: # TODO make this work fx2 = InterfaceTypeFixture() self.assert_subtype(fx2.m1, fx2.gfa) self.assert_not_subtype(fx2.m1, fx2.gfb) self.assert_equivalent(fx2.gfa, fx2.gfa) def test_basic_callable_subtyping(self) -> None: self.assert_strict_subtype( self.fx.callable(self.fx.o, self.fx.d), self.fx.callable(self.fx.a, self.fx.d) ) self.assert_strict_subtype( self.fx.callable(self.fx.d, self.fx.b), self.fx.callable(self.fx.d, self.fx.a) ) self.assert_strict_subtype( self.fx.callable(self.fx.a, UninhabitedType()), self.fx.callable(self.fx.a, self.fx.a) ) self.assert_unrelated( self.fx.callable(self.fx.a, self.fx.a, self.fx.a), self.fx.callable(self.fx.a, self.fx.a), ) def test_default_arg_callable_subtyping(self) -> None: self.assert_strict_subtype( self.fx.callable_default(1, self.fx.a, self.fx.d, self.fx.a), self.fx.callable(self.fx.a, self.fx.d, self.fx.a), ) self.assert_strict_subtype( self.fx.callable_default(1, self.fx.a, self.fx.d, self.fx.a), self.fx.callable(self.fx.a, self.fx.a), ) self.assert_strict_subtype( self.fx.callable_default(0, self.fx.a, self.fx.d, self.fx.a), self.fx.callable_default(1, self.fx.a, self.fx.d, self.fx.a), ) self.assert_unrelated( self.fx.callable_default(1, self.fx.a, self.fx.d, self.fx.a), self.fx.callable(self.fx.d, self.fx.d, self.fx.a), ) self.assert_unrelated( self.fx.callable_default(0, self.fx.a, self.fx.d, self.fx.a), self.fx.callable_default(1, self.fx.a, self.fx.a, self.fx.a), ) self.assert_unrelated( self.fx.callable_default(1, self.fx.a, self.fx.a), self.fx.callable(self.fx.a, self.fx.a, self.fx.a), ) def test_var_arg_callable_subtyping_1(self) -> None: self.assert_strict_subtype( self.fx.callable_var_arg(0, self.fx.a, self.fx.a), self.fx.callable_var_arg(0, self.fx.b, self.fx.a), ) def test_var_arg_callable_subtyping_2(self) -> None: self.assert_strict_subtype( self.fx.callable_var_arg(0, self.fx.a, self.fx.a), self.fx.callable(self.fx.b, self.fx.a), ) def test_var_arg_callable_subtyping_3(self) -> None: self.assert_strict_subtype( self.fx.callable_var_arg(0, self.fx.a, self.fx.a), self.fx.callable(self.fx.a) ) def test_var_arg_callable_subtyping_4(self) -> None: self.assert_strict_subtype( self.fx.callable_var_arg(1, self.fx.a, self.fx.d, self.fx.a), self.fx.callable(self.fx.b, self.fx.a), ) def test_var_arg_callable_subtyping_5(self) -> None: self.assert_strict_subtype( self.fx.callable_var_arg(0, self.fx.a, self.fx.d, self.fx.a), self.fx.callable(self.fx.b, self.fx.a), ) def test_var_arg_callable_subtyping_6(self) -> None: self.assert_strict_subtype( self.fx.callable_var_arg(0, self.fx.a, self.fx.f, self.fx.d), self.fx.callable_var_arg(0, self.fx.b, self.fx.e, self.fx.d), ) def test_var_arg_callable_subtyping_7(self) -> None: self.assert_not_subtype( self.fx.callable_var_arg(0, self.fx.b, self.fx.d), self.fx.callable(self.fx.a, self.fx.d), ) def test_var_arg_callable_subtyping_8(self) -> None: self.assert_not_subtype( self.fx.callable_var_arg(0, self.fx.b, self.fx.d), self.fx.callable_var_arg(0, self.fx.a, self.fx.a, self.fx.d), ) self.assert_subtype( self.fx.callable_var_arg(0, self.fx.a, self.fx.d), self.fx.callable_var_arg(0, self.fx.b, self.fx.b, self.fx.d), ) def test_var_arg_callable_subtyping_9(self) -> None: self.assert_not_subtype( self.fx.callable_var_arg(0, self.fx.b, self.fx.b, self.fx.d), self.fx.callable_var_arg(0, self.fx.a, self.fx.d), ) self.assert_subtype( self.fx.callable_var_arg(0, self.fx.a, self.fx.a, self.fx.d), self.fx.callable_var_arg(0, self.fx.b, self.fx.d), ) def test_type_callable_subtyping(self) -> None: self.assert_subtype(self.fx.callable_type(self.fx.d, self.fx.a), self.fx.type_type) self.assert_strict_subtype( self.fx.callable_type(self.fx.d, self.fx.b), self.fx.callable(self.fx.d, self.fx.a) ) self.assert_strict_subtype( self.fx.callable_type(self.fx.a, self.fx.b), self.fx.callable(self.fx.a, self.fx.b) ) def test_type_var_tuple(self) -> None: self.assert_subtype(Instance(self.fx.gvi, []), Instance(self.fx.gvi, [])) self.assert_subtype( Instance(self.fx.gvi, [self.fx.a, self.fx.b]), Instance(self.fx.gvi, [self.fx.a, self.fx.b]), ) self.assert_not_subtype( Instance(self.fx.gvi, [self.fx.a, self.fx.b]), Instance(self.fx.gvi, [self.fx.b, self.fx.a]), ) self.assert_not_subtype( Instance(self.fx.gvi, [self.fx.a, self.fx.b]), Instance(self.fx.gvi, [self.fx.a]) ) self.assert_subtype( Instance(self.fx.gvi, [UnpackType(self.fx.ss)]), Instance(self.fx.gvi, [UnpackType(self.fx.ss)]), ) self.assert_not_subtype( Instance(self.fx.gvi, [UnpackType(self.fx.ss)]), Instance(self.fx.gvi, [UnpackType(self.fx.us)]), ) self.assert_not_subtype( Instance(self.fx.gvi, [UnpackType(self.fx.ss)]), Instance(self.fx.gvi, []) ) self.assert_not_subtype( Instance(self.fx.gvi, [UnpackType(self.fx.ss)]), Instance(self.fx.gvi, [self.fx.anyt]) ) def test_type_var_tuple_with_prefix_suffix(self) -> None: self.assert_subtype( Instance(self.fx.gvi, [self.fx.a, UnpackType(self.fx.ss)]), Instance(self.fx.gvi, [self.fx.a, UnpackType(self.fx.ss)]), ) self.assert_subtype( Instance(self.fx.gvi, [self.fx.a, self.fx.b, UnpackType(self.fx.ss)]), Instance(self.fx.gvi, [self.fx.a, self.fx.b, UnpackType(self.fx.ss)]), ) self.assert_not_subtype( Instance(self.fx.gvi, [self.fx.a, UnpackType(self.fx.ss)]), Instance(self.fx.gvi, [self.fx.b, UnpackType(self.fx.ss)]), ) self.assert_not_subtype( Instance(self.fx.gvi, [self.fx.a, UnpackType(self.fx.ss)]), Instance(self.fx.gvi, [self.fx.a, self.fx.b, UnpackType(self.fx.ss)]), ) self.assert_subtype( Instance(self.fx.gvi, [UnpackType(self.fx.ss), self.fx.a]), Instance(self.fx.gvi, [UnpackType(self.fx.ss), self.fx.a]), ) self.assert_not_subtype( Instance(self.fx.gvi, [UnpackType(self.fx.ss), self.fx.a]), Instance(self.fx.gvi, [UnpackType(self.fx.ss), self.fx.b]), ) self.assert_not_subtype( Instance(self.fx.gvi, [UnpackType(self.fx.ss), self.fx.a]), Instance(self.fx.gvi, [UnpackType(self.fx.ss), self.fx.a, self.fx.b]), ) self.assert_subtype( Instance(self.fx.gvi, [self.fx.a, self.fx.b, UnpackType(self.fx.ss), self.fx.c]), Instance(self.fx.gvi, [self.fx.a, self.fx.b, UnpackType(self.fx.ss), self.fx.c]), ) self.assert_not_subtype( Instance(self.fx.gvi, [self.fx.a, self.fx.b, UnpackType(self.fx.ss), self.fx.c]), Instance(self.fx.gvi, [self.fx.a, UnpackType(self.fx.ss), self.fx.b, self.fx.c]), ) def test_type_var_tuple_unpacked_variable_length_tuple(self) -> None: self.assert_subtype( Instance(self.fx.gvi, [self.fx.a, self.fx.a]), Instance(self.fx.gvi, [UnpackType(Instance(self.fx.std_tuplei, [self.fx.a]))]), ) def test_fallback_not_subtype_of_tuple(self) -> None: self.assert_not_subtype(self.fx.a, TupleType([self.fx.b], fallback=self.fx.a)) # IDEA: Maybe add these test cases (they are tested pretty well in type # checker tests already): # * more interface subtyping test cases # * more generic interface subtyping test cases # * type variables # * tuple types # * None type # * any type # * generic function types def assert_subtype(self, s: Type, t: Type) -> None: assert is_subtype(s, t), f"{s} not subtype of {t}" def assert_not_subtype(self, s: Type, t: Type) -> None: assert not is_subtype(s, t), f"{s} subtype of {t}" def assert_strict_subtype(self, s: Type, t: Type) -> None: self.assert_subtype(s, t) self.assert_not_subtype(t, s) def assert_equivalent(self, s: Type, t: Type) -> None: self.assert_subtype(s, t) self.assert_subtype(t, s) def assert_unrelated(self, s: Type, t: Type) -> None: self.assert_not_subtype(s, t) self.assert_not_subtype(t, s)