add suffix to every key in object recursively-CodePudding

Function is minimized. It should add "blabla" to every single object key as suffix (recursively).

Error

Type 'any[]' is not assignable to type 'T'.
  'T' could be instantiated with an arbitrary type which could be
    unrelated to 'any[]'.
(2322)

Input

addBlabla([{ a: [{ b: 1 }] }])

Output

{
  ablabla: {
    b: number; // not a "bblabla"
  }[];
}[]

TS playground link

CodePudding user response：

TS playground: https://tsplay.dev/wQKyVm

I removed Array.isArray part because Array is also object (typeof).

CodePudding user response：

You have two errors in the type declaration and the implementation.

In the type, you map every object to the type of himself instead of AddBlabla.

type AddBlaBla<T> = T extends readonly any[]
  ? { [K in keyof T]: AddBlaBla<T[K]> }
  : T extends object
  // ? { [K in keyof T as `${Exclude<K, symbol>}blabla`]: T[K] } // replace this
  ? { [K in keyof T as `${Exclude<K, symbol>}blabla`]: AddBlaBla<T[K]> } // with this
  : T;

The implementation is here.