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=== tests/cases/conformance/types/typeRelationships/assignmentCompatibility/constructSignatureAssignabilityInInheritance3.ts ===
// checking subtype relations for function types as it relates to contextual signature instantiation
// error cases
module Errors {
>Errors : typeof Errors
class Base { foo: string; }
>Base : Base
>foo : string
class Derived extends Base { bar: string; }
>Derived : Derived
>Base : Base
>bar : string
class Derived2 extends Derived { baz: string; }
>Derived2 : Derived2
>Derived : Derived
>baz : string
class OtherDerived extends Base { bing: string; }
>OtherDerived : OtherDerived
>Base : Base
>bing : string
module WithNonGenericSignaturesInBaseType {
// base type with non-generic call signatures
interface A {
a2: new (x: number) => string[];
>a2 : new (x: number) => string[]
>x : number
a7: new (x: (arg: Base) => Derived) => (r: Base) => Derived2;
>a7 : new (x: (arg: Base) => Derived) => (r: Base) => Derived2
>x : (arg: Base) => Derived
>arg : Base
>r : Base
a8: new (x: (arg: Base) => Derived, y: (arg2: Base) => Derived) => (r: Base) => Derived;
>a8 : new (x: (arg: Base) => Derived, y: (arg2: Base) => Derived) => (r: Base) => Derived
>x : (arg: Base) => Derived
>arg : Base
>y : (arg2: Base) => Derived
>arg2 : Base
>r : Base
a10: new (...x: Base[]) => Base;
>a10 : new (...x: Base[]) => Base
>x : Base[]
a11: new (x: { foo: string }, y: { foo: string; bar: string }) => Base;
>a11 : new (x: { foo: string; }, y: { foo: string; bar: string; }) => Base
>x : { foo: string; }
>foo : string
>y : { foo: string; bar: string; }
>foo : string
>bar : string
a12: new (x: Array<Base>, y: Array<Derived2>) => Array<Derived>;
>a12 : new (x: Base[], y: Derived2[]) => Derived[]
>x : Base[]
>y : Derived2[]
a14: {
>a14 : { new (x: number): number[]; new (x: string): string[]; }
new (x: number): number[];
>x : number
new (x: string): string[];
>x : string
};
a15: new (x: { a: string; b: number }) => number;
>a15 : new (x: { a: string; b: number; }) => number
>x : { a: string; b: number; }
>a : string
>b : number
a16: {
>a16 : { new (x: { new (a: number): number; new (a?: number): number; }): number[]; new (x: { new (a: boolean): boolean; new (a?: boolean): boolean; }): boolean[]; }
// type of parameter is overload set which means we can't do inference based on this type
new (x: {
>x : { new (a: number): number; new (a?: number): number; }
new (a: number): number;
>a : number
new (a?: number): number;
>a : number
}): number[];
new (x: {
>x : { new (a: boolean): boolean; new (a?: boolean): boolean; }
new (a: boolean): boolean;
>a : boolean
new (a?: boolean): boolean;
>a : boolean
}): boolean[];
};
}
interface I extends A {
a2: new <T, U>(x: T) => U[]; // error, contextual signature instantiation doesn't relate return types so U is {}, not a subtype of string[]
>a2 : new <T, U>(x: T) => U[]
>x : T
}
interface I2<T, U> extends A {
a2: new (x: T) => U[]; // error, no contextual signature instantiation since I2.a2 is not generic
>a2 : new (x: T) => U[]
>x : T
}
interface I3 extends A {
// valid, no inferences for V so it defaults to Derived2
a7: new <T extends Base, U extends Derived, V extends Derived2>(x: (arg: T) => U) => (r: T) => V;
>a7 : new <T extends Base, U extends Derived, V extends Derived2>(x: (arg: T) => U) => (r: T) => V
>x : (arg: T) => U
>arg : T
>r : T
}
interface I4 extends A {
a8: new <T extends Base, U extends Derived>(x: (arg: T) => U, y: (arg2: { foo: number; }) => U) => (r: T) => U; // error, type mismatch
>a8 : new <T extends Base, U extends Derived>(x: (arg: T) => U, y: (arg2: { foo: number; }) => U) => (r: T) => U
>x : (arg: T) => U
>arg : T
>y : (arg2: { foo: number; }) => U
>arg2 : { foo: number; }
>foo : number
>r : T
}
interface I4B extends A {
a10: new <T extends Derived>(...x: T[]) => T; // valid, parameter covariance works even after contextual signature instantiation
>a10 : new <T extends Derived>(...x: T[]) => T
>x : T[]
}
interface I4C extends A {
a11: new <T extends Derived>(x: T, y: T) => T; // valid, even though x is a Base, parameter covariance works even after contextual signature instantiation
>a11 : new <T extends Derived>(x: T, y: T) => T
>x : T
>y : T
}
interface I4E extends A {
a12: new <T extends Array<Derived2>>(x: Array<Base>, y: Array<Base>) => T; // valid, no inferences for T, defaults to Array<Derived2>
>a12 : new <T extends Derived2[]>(x: Base[], y: Base[]) => T
>x : Base[]
>y : Base[]
}
interface I6 extends A {
a15: new <T>(x: { a: T; b: T }) => T; // error, T is {} which isn't an acceptable return type
>a15 : new <T>(x: { a: T; b: T; }) => T
>x : { a: T; b: T; }
>a : T
>b : T
}
interface I7 extends A {
a15: new <T extends Base>(x: { a: T; b: T }) => number; // error, T defaults to Base, which is not compatible with number or string
>a15 : new <T extends Base>(x: { a: T; b: T; }) => number
>x : { a: T; b: T; }
>a : T
>b : T
}
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: new <T>(x: new (a: T) => T) => T[];
>a16 : new <T>(x: new (a: T) => T) => T[]
>x : new (a: T) => T
>a : T
}
}
module WithGenericSignaturesInBaseType {
// base type has generic call signature
interface B {
a2: new <T>(x: T) => T[];
>a2 : new <T>(x: T) => T[]
>x : T
}
interface I6 extends B {
a2: new <T>(x: T) => string[]; // error
>a2 : new <T>(x: T) => string[]
>x : T
}
// base type has generic call signature
interface C {
a2: new <T>(x: T) => string[];
>a2 : new <T>(x: T) => string[]
>x : T
}
interface I7 extends C {
a2: new <T>(x: T) => T[]; // error
>a2 : new <T>(x: T) => T[]
>x : T
}
// base type has a generic call signature with overloads
interface D {
a14: {
>a14 : { new <T extends Derived>(x: T): number[]; new <U extends Base>(x: U): number[]; }
new <T extends Derived>(x: T): number[];
>x : T
new <U extends Base>(x: U): number[];
>x : U
};
}
interface I8 extends D {
a14: new <T extends Base>(x: T) => number[];
>a14 : new <T extends Base>(x: T) => number[]
>x : T
}
}
}
|
