@reduxjs/toolkit/src/query/tsHelpers.ts

The official, opinionated, batteries-included toolset for efficient Redux development

export type Id<T> = { [K in keyof T]: T[K] } & {}
export type WithRequiredProp<T, K extends keyof T> = Omit<T, K> &
  Required<Pick<T, K>>
export type Override<T1, T2> = T2 extends any ? Omit<T1, keyof T2> & T2 : never
export function assertCast<T>(v: any): asserts v is T {}

export function safeAssign<T extends object>(
  target: T,
  ...args: Array<Partial<NoInfer<T>>>
) {
  Object.assign(target, ...args)
}

/**
 * Convert a Union type `(A|B)` to an intersection type `(A&B)`
 */
export type UnionToIntersection<U> = (
  U extends any ? (k: U) => void : never
) extends (k: infer I) => void
  ? I
  : never

export type NonOptionalKeys<T> = {
  [K in keyof T]-?: undefined extends T[K] ? never : K
}[keyof T]

export type HasRequiredProps<T, True, False> = NonOptionalKeys<T> extends never
  ? False
  : True

export type OptionalIfAllPropsOptional<T> = HasRequiredProps<T, T, T | never>

export type NoInfer<T> = [T][T extends any ? 0 : never]

export type UnwrapPromise<T> = T extends PromiseLike<infer V> ? V : T

export type MaybePromise<T> = T | PromiseLike<T>

export type OmitFromUnion<T, K extends keyof T> = T extends any
  ? Omit<T, K>
  : never

export type IsAny<T, True, False = never> = true | false extends (
  T extends never ? true : false
)
  ? True
  : False

export type CastAny<T, CastTo> = IsAny<T, CastTo, T>