e2ed/types/brand.d.ts

E2E testing framework over Playwright

/**
 * Inner key for brand types.
 */
declare const BRAND: unique symbol;
/**
 * Creates brand (nominal) type from regular type.
 * `Brand<string, 'OrderId'>` = `OrderId` (A string that can only be getting from the API).
 */
export type Brand<Type, Key extends string> = Type & {
    readonly [BRAND]: Key;
};
/**
 * Returns `true`, if T is brand type, and `false` otherwise.
 * `IsBrand<3>` = `false`.
 * `IsBrand<Brand<3, 'foo'>` = `true`.
 */
export type IsBrand<Type> = [Type] extends [{
    [BRAND]: unknown;
}] ? true : false;
export {};