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|
=== tests/cases/compiler/inferenceErasedSignatures.ts ===
// Repro from #37163
declare class SomeBaseClass {
>SomeBaseClass : SomeBaseClass
set<K extends keyof this>(key: K, value: this[K]): this[K];
>set : <K extends keyof this>(key: K, value: this[K]) => this[K]
>key : K
>value : this[K]
}
abstract class SomeAbstractClass<C, M, R> extends SomeBaseClass {
>SomeAbstractClass : SomeAbstractClass<C, M, R>
>SomeBaseClass : SomeBaseClass
foo!: (r?: R) => void;
>foo : (r?: R) => void
>r : R | undefined
bar!: (r?: any) => void;
>bar : (r?: any) => void
>r : any
abstract baz(c: C): Promise<M>;
>baz : (c: C) => Promise<M>
>c : C
}
class SomeClass extends SomeAbstractClass<number, string, boolean> {
>SomeClass : SomeClass
>SomeAbstractClass : SomeAbstractClass<number, string, boolean>
async baz(context: number): Promise<string> {
>baz : (context: number) => Promise<string>
>context : number
return `${context}`;
>`${context}` : string
>context : number
}
}
type CType<T> = T extends SomeAbstractClass<infer C, any, any> ? C : never;
>CType : CType<T>
type MType<T> = T extends SomeAbstractClass<any, infer M, any> ? M : never;
>MType : MType<T>
type RType<T> = T extends SomeAbstractClass<any, any, infer R> ? R : never;
>RType : RType<T>
type SomeClassC = CType<SomeClass>; // number
>SomeClassC : number
type SomeClassM = MType<SomeClass>; // string
>SomeClassM : string
type SomeClassR = RType<SomeClass>; // boolean
>SomeClassR : boolean
// Repro from #37163
interface BaseType<T1, T2> {
set<K extends keyof this>(key: K, value: this[K]): this[K];
>set : <K extends keyof this>(key: K, value: this[K]) => this[K]
>key : K
>value : this[K]
useT1(c: T1): void;
>useT1 : (c: T1) => void
>c : T1
useT2(r?: T2): void;
>useT2 : (r?: T2) => void
>r : T2 | undefined
unrelatedButSomehowRelevant(r?: any): void;
>unrelatedButSomehowRelevant : (r?: any) => void
>r : any
}
interface InheritedType extends BaseType<number, boolean> {
// This declaration shouldn't do anything...
useT1(_: number): void
>useT1 : (_: number) => void
>_ : number
}
// Structural expansion of InheritedType
interface StructuralVersion {
set<K extends keyof this>(key: K, value: this[K]): this[K];
>set : <K extends keyof this>(key: K, value: this[K]) => this[K]
>key : K
>value : this[K]
useT1(c: number): void;
>useT1 : (c: number) => void
>c : number
useT2(r?: boolean): void;
>useT2 : (r?: boolean) => void
>r : boolean | undefined
unrelatedButSomehowRelevant(r?: any): void;
>unrelatedButSomehowRelevant : (r?: any) => void
>r : any
}
type GetT1<T> = T extends BaseType<infer U, any> ? U : never;
>GetT1 : GetT1<T>
type T1 = GetT1<InheritedType>; // number
>T1 : number
type T2 = GetT1<StructuralVersion>; // number
>T2 : number
|
