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//// [callSignatureAssignabilityInInheritance3.ts]
// checking subtype relations for function types as it relates to contextual signature instantiation
// error cases
module Errors {
class Base { foo: string; }
class Derived extends Base { bar: string; }
class Derived2 extends Derived { baz: string; }
class OtherDerived extends Base { bing: string; }
module WithNonGenericSignaturesInBaseType {
// base type with non-generic call signatures
interface A {
a2: (x: number) => string[];
a7: (x: (arg: Base) => Derived) => (r: Base) => Derived2;
a8: (x: (arg: Base) => Derived, y: (arg2: Base) => Derived) => (r: Base) => Derived;
a10: (...x: Base[]) => Base;
a11: (x: { foo: string }, y: { foo: string; bar: string }) => Base;
a12: (x: Array<Base>, y: Array<Derived2>) => Array<Derived>;
a14: {
(x: number): number[];
(x: string): string[];
};
a15: (x: { a: string; b: number }) => number;
a16: {
// type of parameter is overload set which means we can't do inference based on this type
(x: {
(a: number): number;
(a?: number): number;
}): number[];
(x: {
(a: boolean): boolean;
(a?: boolean): boolean;
}): boolean[];
};
a17: {
(x: {
<T extends Derived>(a: T): T;
<T extends Base>(a: T): T;
}): any[];
(x: {
<T extends Derived2>(a: T): T;
<T extends Base>(a: T): T;
}): any[];
};
}
interface I extends A {
a2: <T, U>(x: T) => U[]; // error, contextual signature instantiation doesn't relate return types so U is {}, not a subtype of string[]
}
interface I2<T, U> extends A {
a2: (x: T) => U[]; // error, no contextual signature instantiation since I2.a2 is not generic
}
interface I3 extends A {
// valid, no inferences for V so it defaults to Derived2
a7: <T extends Base, U extends Derived, V extends Derived2>(x: (arg: T) => U) => (r: T) => V;
}
interface I4 extends A {
a8: <T extends Base, U extends Derived>(x: (arg: T) => U, y: (arg2: { foo: number; }) => U) => (r: T) => U; // error, type mismatch
}
interface I4B extends A {
a10: <T extends Derived>(...x: T[]) => T; // valid, parameter covariance works even after contextual signature instantiation
}
interface I4C extends A {
a11: <T extends Derived>(x: T, y: T) => T; // valid, even though x is a Base, parameter covariance works even after contextual signature instantiation
}
interface I4E extends A {
a12: <T extends Array<Derived2>>(x: Array<Base>, y: Array<Base>) => T; // valid, no inferences for T, defaults to Array<Derived2>
}
interface I6 extends A {
a15: <T>(x: { a: T; b: T }) => T; // error, T is {} which isn't an acceptable return type
}
interface I7 extends A {
a15: <T extends Base>(x: { a: T; b: T }) => number; // error, T defaults to Base, which is not compatible with number or string
}
interface I8 extends A {
// ok, we relate each signature of a16 to b16, and within that, we make inferences from two different signatures in the respective A.a16 signature
a16: <T>(x: (a: T) => T) => T[];
}
interface I9 extends A {
a17: <T>(x: (a: T) => T) => any[]; // valid, target is more constrained than source, so it is safe in the traditional constraint-contravariant fashion
}
}
module WithGenericSignaturesInBaseType {
// base type has generic call signature
interface B {
a2: <T>(x: T) => T[];
}
interface I6 extends B {
a2: <T>(x: T) => string[]; // error
}
// base type has generic call signature
interface C {
a2: <T>(x: T) => string[];
}
interface I7 extends C {
a2: <T>(x: T) => T[]; // error
}
}
}
//// [callSignatureAssignabilityInInheritance3.js]
// checking subtype relations for function types as it relates to contextual signature instantiation
// error cases
var __extends = (this && this.__extends) || (function () {
var extendStatics = function (d, b) {
extendStatics = Object.setPrototypeOf ||
({ __proto__: [] } instanceof Array && function (d, b) { d.__proto__ = b; }) ||
function (d, b) { for (var p in b) if (b.hasOwnProperty(p)) d[p] = b[p]; };
return extendStatics(d, b);
};
return function (d, b) {
extendStatics(d, b);
function __() { this.constructor = d; }
d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
};
})();
var Errors;
(function (Errors) {
var Base = /** @class */ (function () {
function Base() {
}
return Base;
}());
var Derived = /** @class */ (function (_super) {
__extends(Derived, _super);
function Derived() {
return _super !== null && _super.apply(this, arguments) || this;
}
return Derived;
}(Base));
var Derived2 = /** @class */ (function (_super) {
__extends(Derived2, _super);
function Derived2() {
return _super !== null && _super.apply(this, arguments) || this;
}
return Derived2;
}(Derived));
var OtherDerived = /** @class */ (function (_super) {
__extends(OtherDerived, _super);
function OtherDerived() {
return _super !== null && _super.apply(this, arguments) || this;
}
return OtherDerived;
}(Base));
})(Errors || (Errors = {}));
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