TypeScript/tests/cases/compiler/inferFromGenericFunctionReturnTypes3.ts
2019-05-30 14:40:03 -07:00

204 lines
3.9 KiB
TypeScript

// @strict: true
// @target: es6
// @declaration: true
// Repros from #5487
function truePromise(): Promise<true> {
return Promise.resolve(true);
}
interface Wrap<T> {
value: T;
}
function wrap<T>(value: T): Wrap<T> {
return { value };
}
function wrappedFoo(): Wrap<'foo'> {
return wrap('foo');
}
function wrapBar(value: 'bar'): Wrap<'bar'> {
return { value };
}
function wrappedBar(): Wrap<'bar'> {
const value = 'bar';
const inferred = wrapBar(value);
const literal = wrapBar('bar');
const value2: string = 'bar';
const literal2 = wrapBar(value2); // Error
return wrap(value);
}
function wrappedBaz(): Wrap<'baz'> {
const value: 'baz' = 'baz';
return wrap(value);
}
// Repro from #11152
interface FolderContentItem {
type: 'folder' | 'file';
}
let a: FolderContentItem[] = [];
a = [1, 2, 3, 4, 5].map(v => ({ type: 'folder' }));
// Repro from #11312
let arr: Array<[number, number]> = [[1, 2]]
let mappedArr: Array<[number, number]> = arr.map(([x, y]) => {
return [x, y];
})
// Repro from #13594
export namespace DiagnosticSeverity {
export const Error = 1;
export const Warning = 2;
export const Information = 3;
export const Hint = 4;
}
export type DiagnosticSeverity = 1 | 2 | 3 | 4;
export interface Diagnostic {
severity?: DiagnosticSeverity;
code?: number | string;
source?: string;
message: string;
}
function bug(): Diagnostic[] {
let values: any[] = [];
return values.map((value) => {
return {
severity: DiagnosticSeverity.Error,
message: 'message'
}
});
}
// Repro from #22870
function objectToMap(obj: any) {
return new Map(Object.keys(obj).map(key => [key, obj[key]]));
};
// Repro from #24352
interface Person {
phoneNumbers: {
__typename: 'PhoneNumber';
}[];
}
function createPerson(): Person {
return {
phoneNumbers: [1].map(() => ({
__typename: 'PhoneNumber'
}))
};
}
// Repro from #26621
type Box<T> = { value: T };
declare function box<T>(value: T): Box<T>;
type WinCondition =
| { type: 'win', player: string }
| { type: 'draw' };
let zz: Box<WinCondition> = box({ type: 'draw' });
type WinType = 'win' | 'draw';
let yy: Box<WinType> = box('draw');
// Repro from #27074
interface OK<T> {
kind: "OK";
value: T;
}
export function ok<T>(value: T): OK<T> {
return {
kind: "OK",
value: value
};
}
let result: OK<[string, number]> = ok(["hello", 12]);
// Repro from #25889
interface I {
code: 'mapped',
name: string,
}
const a3: I[] = ['a', 'b'].map(name => {
return {
code: 'mapped',
name,
}
});
// Repro from https://www.memsql.com/blog/porting-30k-lines-of-code-from-flow-to-typescript/
type Player = {
name: string;
age: number;
position: "STRIKER" | "GOALKEEPER",
};
type F = () => Promise<Array<Player>>;
const f1: F = () => {
return Promise.all([
{
name: "David Gomes",
age: 23,
position: "GOALKEEPER",
}, {
name: "Cristiano Ronaldo",
age: 33,
position: "STRIKER",
}
]);
};
// Breaking change repros from #29478
declare function foldLeft<U>(z: U, f: (acc: U, t: boolean) => U): U;
let res: boolean = foldLeft(true, (acc, t) => acc && t); // Error
enum State { A, B }
type Foo = { state: State }
declare function bar<T>(f: () => T[]): T[];
let x: Foo[] = bar(() => !!true ? [{ state: State.A }] : [{ state: State.B }]); // Error
// Repros from #31443
enum Enum { A, B }
class ClassWithConvert<T> {
constructor(val: T) { }
convert(converter: { to: (v: T) => T; }) { }
}
function fn<T>(arg: ClassWithConvert<T>, f: () => ClassWithConvert<T>) { }
fn(new ClassWithConvert(Enum.A), () => new ClassWithConvert(Enum.A));
type Func<T> = (x: T) => T;
declare function makeFoo<T>(x: T): Func<T>;
declare function baz<U>(x: Func<U>, y: Func<U>): void;
baz(makeFoo(Enum.A), makeFoo(Enum.A));