better-auth/dist/types/helper.d.mts

The most comprehensive authentication framework for TypeScript.

//#region src/types/helper.d.ts
type IsAny<T> = 0 extends 1 & T ? true : false;
type Prettify<T> = Omit<T, never>;
type PrettifyDeep<T> = { [K in keyof T]: T[K] extends ((...args: any[]) => any) ? T[K] : T[K] extends object ? T[K] extends Array<any> ? T[K] : T[K] extends Date ? T[K] : PrettifyDeep<T[K]> : T[K] } & {};
type UnionToIntersection<U> = (U extends any ? (k: U) => void : never) extends ((k: infer I) => void) ? I : never;
type RequiredKeysOf<BaseType extends object> = Exclude<{ [Key in keyof BaseType]: BaseType extends Record<Key, BaseType[Key]> ? Key : never }[keyof BaseType], undefined>;
type HasRequiredKeys<BaseType> = IsAny<BaseType> extends true ? false : [BaseType] extends [object] ? RequiredKeysOf<BaseType & object> extends never ? false : true : false;
type StripEmptyObjects<T extends object> = { [K in keyof T]: T[K] };
/**
 * Object merge replacing `Base`'s keys with `Override`'s.
 * The naive `Omit<Base, keyof Override> & Override` form breaks under generics.
 *
 * @see https://github.com/microsoft/TypeScript/issues/57466#issuecomment-1957988380
 */
type OverrideMerge<Base, Override> = Base extends unknown ? Override extends unknown ? Prettify<{ [K in keyof Base as K extends keyof Override ? never : K]: Base[K] } & Override> : never : never;
/**
 * Extracts a Record-typed field from a plugin, guarding against `any`.
 */
type ExtractPluginField<T, Field extends string> = IsAny<T> extends true ? {} : T extends { [K in Field]?: Record<string, any> } ? T[Field] extends Record<string, any> ? T[Field] : {} : {};
/**
 * Walks a plugin tuple with tail-recursive accumulator (TS 4.5+),
 * extracting and intersecting the given field from each element.
 */
type InferPluginFieldFromTuple<T extends readonly unknown[], Field extends string, Acc = {}> = T extends readonly [infer Head, ...infer Tail] ? InferPluginFieldFromTuple<Tail, Field, Acc & ExtractPluginField<Head, Field>> : Acc;
//#endregion
export { ExtractPluginField, HasRequiredKeys, InferPluginFieldFromTuple, IsAny, OverrideMerge, Prettify, PrettifyDeep, RequiredKeysOf, StripEmptyObjects, UnionToIntersection };