e2ed
Version:
E2E testing framework over Playwright
17 lines (16 loc) • 744 B
TypeScript
/**
* This type checks that the type `true` is passed to it.
*/
export type Expect<Type extends true> = Type;
/**
* Returns `true` if types are exactly equal and `false` otherwise.
* IsEqual<{foo: string}, {foo: string}> = true.
* IsEqual<{readonly foo: string}, {foo: string}> = false.
*/
export type IsEqual<X, Y> = (<Type>() => Type extends X ? 1 : 2) extends <Type>() => Type extends Y ? 1 : 2 ? true : false;
/**
* Returns `true` if key is readonly in object and `false` otherwise.
* IsReadonlyKey<{readonly foo?: 2}, 'foo'> = true.
* IsReadonlyKey<{foo: ''}, 'foo'> = false.
*/
export type IsReadonlyKey<SomeObject extends object, Key extends keyof SomeObject> = IsEqual<Readonly<Pick<SomeObject, Key>>, Pick<SomeObject, Key>>;