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=== tests/cases/compiler/arrayFrom.ts ===
// Tests fix for #20432, ensures Array.from accepts all valid inputs
// Also tests for #19682
interface A {
a: string;
>a : string
}
interface B {
b: string;
>b : string
}
const inputA: A[] = [];
>inputA : A[]
>[] : undefined[]
const inputB: B[] = [];
>inputB : B[]
>[] : undefined[]
const inputALike: ArrayLike<A> = { length: 0 };
>inputALike : ArrayLike<A>
>{ length: 0 } : { length: number; }
>length : number
>0 : 0
const inputARand = getEither(inputA, inputALike);
>inputARand : ArrayLike<A> | Iterable<A>
>getEither(inputA, inputALike) : ArrayLike<A> | Iterable<A>
>getEither : <T>(in1: Iterable<T>, in2: ArrayLike<T>) => Iterable<T> | ArrayLike<T>
>inputA : A[]
>inputALike : ArrayLike<A>
const inputASet = new Set<A>();
>inputASet : Set<A>
>new Set<A>() : Set<A>
>Set : SetConstructor
const result1: A[] = Array.from(inputA);
>result1 : A[]
>Array.from(inputA) : A[]
>Array.from : { <T>(arrayLike: ArrayLike<T>): T[]; <T, U>(arrayLike: ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; <T>(iterable: Iterable<T> | ArrayLike<T>): T[]; <T, U>(iterable: Iterable<T> | ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; }
>Array : ArrayConstructor
>from : { <T>(arrayLike: ArrayLike<T>): T[]; <T, U>(arrayLike: ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; <T>(iterable: Iterable<T> | ArrayLike<T>): T[]; <T, U>(iterable: Iterable<T> | ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; }
>inputA : A[]
const result2: A[] = Array.from(inputA.values());
>result2 : A[]
>Array.from(inputA.values()) : A[]
>Array.from : { <T>(arrayLike: ArrayLike<T>): T[]; <T, U>(arrayLike: ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; <T>(iterable: Iterable<T> | ArrayLike<T>): T[]; <T, U>(iterable: Iterable<T> | ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; }
>Array : ArrayConstructor
>from : { <T>(arrayLike: ArrayLike<T>): T[]; <T, U>(arrayLike: ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; <T>(iterable: Iterable<T> | ArrayLike<T>): T[]; <T, U>(iterable: Iterable<T> | ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; }
>inputA.values() : IterableIterator<A>
>inputA.values : () => IterableIterator<A>
>inputA : A[]
>values : () => IterableIterator<A>
const result3: B[] = Array.from(inputA.values()); // expect error
>result3 : B[]
>Array.from(inputA.values()) : A[]
>Array.from : { <T>(arrayLike: ArrayLike<T>): T[]; <T, U>(arrayLike: ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; <T>(iterable: Iterable<T> | ArrayLike<T>): T[]; <T, U>(iterable: Iterable<T> | ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; }
>Array : ArrayConstructor
>from : { <T>(arrayLike: ArrayLike<T>): T[]; <T, U>(arrayLike: ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; <T>(iterable: Iterable<T> | ArrayLike<T>): T[]; <T, U>(iterable: Iterable<T> | ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; }
>inputA.values() : IterableIterator<A>
>inputA.values : () => IterableIterator<A>
>inputA : A[]
>values : () => IterableIterator<A>
const result4: A[] = Array.from(inputB, ({ b }): A => ({ a: b }));
>result4 : A[]
>Array.from(inputB, ({ b }): A => ({ a: b })) : A[]
>Array.from : { <T>(arrayLike: ArrayLike<T>): T[]; <T, U>(arrayLike: ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; <T>(iterable: Iterable<T> | ArrayLike<T>): T[]; <T, U>(iterable: Iterable<T> | ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; }
>Array : ArrayConstructor
>from : { <T>(arrayLike: ArrayLike<T>): T[]; <T, U>(arrayLike: ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; <T>(iterable: Iterable<T> | ArrayLike<T>): T[]; <T, U>(iterable: Iterable<T> | ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; }
>inputB : B[]
>({ b }): A => ({ a: b }) : ({ b }: B) => A
>b : string
>({ a: b }) : { a: string; }
>{ a: b } : { a: string; }
>a : string
>b : string
const result5: A[] = Array.from(inputALike);
>result5 : A[]
>Array.from(inputALike) : A[]
>Array.from : { <T>(arrayLike: ArrayLike<T>): T[]; <T, U>(arrayLike: ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; <T>(iterable: Iterable<T> | ArrayLike<T>): T[]; <T, U>(iterable: Iterable<T> | ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; }
>Array : ArrayConstructor
>from : { <T>(arrayLike: ArrayLike<T>): T[]; <T, U>(arrayLike: ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; <T>(iterable: Iterable<T> | ArrayLike<T>): T[]; <T, U>(iterable: Iterable<T> | ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; }
>inputALike : ArrayLike<A>
const result6: B[] = Array.from(inputALike); // expect error
>result6 : B[]
>Array.from(inputALike) : A[]
>Array.from : { <T>(arrayLike: ArrayLike<T>): T[]; <T, U>(arrayLike: ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; <T>(iterable: Iterable<T> | ArrayLike<T>): T[]; <T, U>(iterable: Iterable<T> | ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; }
>Array : ArrayConstructor
>from : { <T>(arrayLike: ArrayLike<T>): T[]; <T, U>(arrayLike: ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; <T>(iterable: Iterable<T> | ArrayLike<T>): T[]; <T, U>(iterable: Iterable<T> | ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; }
>inputALike : ArrayLike<A>
const result7: B[] = Array.from(inputALike, ({ a }): B => ({ b: a }));
>result7 : B[]
>Array.from(inputALike, ({ a }): B => ({ b: a })) : B[]
>Array.from : { <T>(arrayLike: ArrayLike<T>): T[]; <T, U>(arrayLike: ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; <T>(iterable: Iterable<T> | ArrayLike<T>): T[]; <T, U>(iterable: Iterable<T> | ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; }
>Array : ArrayConstructor
>from : { <T>(arrayLike: ArrayLike<T>): T[]; <T, U>(arrayLike: ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; <T>(iterable: Iterable<T> | ArrayLike<T>): T[]; <T, U>(iterable: Iterable<T> | ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; }
>inputALike : ArrayLike<A>
>({ a }): B => ({ b: a }) : ({ a }: A) => B
>a : string
>({ b: a }) : { b: string; }
>{ b: a } : { b: string; }
>b : string
>a : string
const result8: A[] = Array.from(inputARand);
>result8 : A[]
>Array.from(inputARand) : A[]
>Array.from : { <T>(arrayLike: ArrayLike<T>): T[]; <T, U>(arrayLike: ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; <T>(iterable: Iterable<T> | ArrayLike<T>): T[]; <T, U>(iterable: Iterable<T> | ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; }
>Array : ArrayConstructor
>from : { <T>(arrayLike: ArrayLike<T>): T[]; <T, U>(arrayLike: ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; <T>(iterable: Iterable<T> | ArrayLike<T>): T[]; <T, U>(iterable: Iterable<T> | ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; }
>inputARand : ArrayLike<A> | Iterable<A>
const result9: B[] = Array.from(inputARand, ({ a }): B => ({ b: a }));
>result9 : B[]
>Array.from(inputARand, ({ a }): B => ({ b: a })) : B[]
>Array.from : { <T>(arrayLike: ArrayLike<T>): T[]; <T, U>(arrayLike: ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; <T>(iterable: Iterable<T> | ArrayLike<T>): T[]; <T, U>(iterable: Iterable<T> | ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; }
>Array : ArrayConstructor
>from : { <T>(arrayLike: ArrayLike<T>): T[]; <T, U>(arrayLike: ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; <T>(iterable: Iterable<T> | ArrayLike<T>): T[]; <T, U>(iterable: Iterable<T> | ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; }
>inputARand : ArrayLike<A> | Iterable<A>
>({ a }): B => ({ b: a }) : ({ a }: A) => B
>a : string
>({ b: a }) : { b: string; }
>{ b: a } : { b: string; }
>b : string
>a : string
const result10: A[] = Array.from(new Set<A>());
>result10 : A[]
>Array.from(new Set<A>()) : A[]
>Array.from : { <T>(arrayLike: ArrayLike<T>): T[]; <T, U>(arrayLike: ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; <T>(iterable: Iterable<T> | ArrayLike<T>): T[]; <T, U>(iterable: Iterable<T> | ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; }
>Array : ArrayConstructor
>from : { <T>(arrayLike: ArrayLike<T>): T[]; <T, U>(arrayLike: ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; <T>(iterable: Iterable<T> | ArrayLike<T>): T[]; <T, U>(iterable: Iterable<T> | ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; }
>new Set<A>() : Set<A>
>Set : SetConstructor
const result11: B[] = Array.from(inputASet, ({ a }): B => ({ b: a }));
>result11 : B[]
>Array.from(inputASet, ({ a }): B => ({ b: a })) : B[]
>Array.from : { <T>(arrayLike: ArrayLike<T>): T[]; <T, U>(arrayLike: ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; <T>(iterable: Iterable<T> | ArrayLike<T>): T[]; <T, U>(iterable: Iterable<T> | ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; }
>Array : ArrayConstructor
>from : { <T>(arrayLike: ArrayLike<T>): T[]; <T, U>(arrayLike: ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; <T>(iterable: Iterable<T> | ArrayLike<T>): T[]; <T, U>(iterable: Iterable<T> | ArrayLike<T>, mapfn: (v: T, k: number) => U, thisArg?: any): U[]; }
>inputASet : Set<A>
>({ a }): B => ({ b: a }) : ({ a }: A) => B
>a : string
>({ b: a }) : { b: string; }
>{ b: a } : { b: string; }
>b : string
>a : string
// if this is written inline, the compiler seems to infer
// the ?: as always taking the false branch, narrowing to ArrayLike<T>,
// even when the type is written as : Iterable<T>|ArrayLike<T>
function getEither<T> (in1: Iterable<T>, in2: ArrayLike<T>) {
>getEither : <T>(in1: Iterable<T>, in2: ArrayLike<T>) => Iterable<T> | ArrayLike<T>
>in1 : Iterable<T>
>in2 : ArrayLike<T>
return Math.random() > 0.5 ? in1 : in2;
>Math.random() > 0.5 ? in1 : in2 : Iterable<T> | ArrayLike<T>
>Math.random() > 0.5 : boolean
>Math.random() : number
>Math.random : () => number
>Math : Math
>random : () => number
>0.5 : 0.5
>in1 : Iterable<T>
>in2 : ArrayLike<T>
}
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