rambdax/_ts-toolbelt/src/Object/Compulsory.ts

Extended version of Rambda - a lightweight, faster alternative to Ramda

import {_Pick} from './Pick'
import {Depth} from './_Internal'
import {Key} from '../Any/Key'
import {NonNullable} from '../Union/NonNullable'
import {_PatchFlat} from './Patch'
import {BuiltInObject} from '../Misc/BuiltInObject'

/**
@hidden
*/
export type CompulsoryFlat<O> = {
    [K in keyof O]-?: NonNullable<O[K]>
} & {}

/**
@hidden
*/
export type CompulsoryDeep<O> = {
    [K in keyof O]-?: O[K] extends BuiltInObject
                      ? O[K]
                      : CompulsoryDeep<NonNullable<O[K]>>
}

/**
@hidden
*/
export type CompulsoryPart<O extends object, depth extends Depth> = {
    'flat': CompulsoryFlat<O>,
    'deep': CompulsoryDeep<O>,
}[depth]

/**
 * @hidden
 */
export type _Compulsory<O extends object, K extends Key, depth extends Depth> =
    _PatchFlat<CompulsoryPart<_Pick<O, K>, depth>, O, 2>

/**
Make that `O`'s fields cannot be [[Nullable]] or [[Optional]] (it's like
[[Required]] & [[NonNullable]] at once).
@param O to make compulsory
@param K (?=`Key`) to choose fields
@param depth (?=`'flat'`) to do it deeply
@returns [[Object]]
@example
```ts
```
*/
export type Compulsory<O extends object, K extends Key = Key, depth extends Depth = 'flat'> =
    O extends unknown
    ? _Compulsory<O, K, depth>
    : never