| // Copyright (c) 2018, the Dart project authors. Please see the AUTHORS file |
| // for details. All rights reserved. Use of this source code is governed by a |
| // BSD-style license that can be found in the LICENSE file. |
| |
| import "package:expect/expect.dart"; |
| |
| // Test various invalid super-constraints for mixin declarations. |
| |
| abstract class BinaryNumInt { |
| num foo(num x, int y); |
| } |
| |
| abstract class BinaryIntNum { |
| num foo(int x, num y); |
| } |
| |
| abstract class GetterNumNum { |
| num Function(num) get foo; |
| } |
| |
| abstract class GetterIntInt { |
| int Function(int) get foo; |
| } |
| |
| abstract class UnaryInt { |
| num foo(int x); |
| } |
| |
| abstract class UnaryNum { |
| num foo(num x); |
| } |
| |
| abstract class UnaryString { |
| num foo(String x); |
| } |
| |
| // The super-interfaces must be *compatible*. |
| // Any member declared by more than one super-interface must have at |
| // least one most-specific signature among the super-interfaces. |
| |
| // Incompatible member kinds, one is a getter, the other a method. |
| mixin _ on UnaryNum, GetterNumNum {} //# 01: compile-time error |
| |
| // Incompatible signature structure, unary vs binary. |
| mixin _ on UnaryNum, BinaryNumInt {} //# 02: compile-time error |
| |
| // Incompatible method parameter type, neither is more specific. |
| mixin _ on UnaryNum, UnaryString {} //# 03: compile-time error |
| |
| // Compatible types for each parameter, but still no most specific signature. |
| mixin _ on BinaryNumInt, BinaryIntNum {} //# 04: compile-time error |
| |
| // Incompatible return type for getter. |
| mixin _ on GetterNumNum, GetterIntInt {} //# 05: compile-time error |
| |
| |
| // Mixin is valid when one signature is more specific. |
| mixin M1 on UnaryNum, UnaryInt { |
| // May call the method in a super-invocation, at the most specific type. |
| num bar() { |
| return super.foo(42.0); |
| } |
| } |
| |
| class C1 implements UnaryNum, UnaryInt { |
| num foo(num x) => x; |
| } |
| |
| class A1 = C1 with M1; |
| |
| main() { |
| Expect.equals(42.0, A1().bar()); |
| } |