119-replaceall.ts

/**
 * 119 - ReplaceAll
 *
 * Implement `ReplaceAll<S, From, To>` which replace the all the substring `From` with `To` in the given string `S`
 *
 * For example
 *
 * ```ts
 * type replaced = ReplaceAll<'t y p e s', ' ', ''> // expected to be 'types'
 * ```
 */

/* _____________ Your Code Here _____________ */

type ReplaceAll<
  S extends string,
  From extends string,
  To extends string
> = From extends ''
  ? S
  : S extends `${infer A}${From}${infer B}`
    ? `${A}${To}${ReplaceAll<B, From, To>}`
    : S;

/* _____________ Test Cases _____________ */
import type { Equal, Expect } from '@type-challenges/utils'

type cases = [
  Expect<Equal<ReplaceAll<'foobar', 'bar', 'foo'>, 'foofoo'>>,
  Expect<Equal<ReplaceAll<'foobar', 'bag', 'foo'>, 'foobar'>>,
  Expect<Equal<ReplaceAll<'foobarbar', 'bar', 'foo'>, 'foofoofoo'>>,
  Expect<Equal<ReplaceAll<'t y p e s', ' ', ''>, 'types'>>,
  Expect<Equal<ReplaceAll<'foobarbar', '', 'foo'>, 'foobarbar'>>,
  Expect<Equal<ReplaceAll<'barfoo', 'bar', 'foo'>, 'foofoo'>>,
  Expect<Equal<ReplaceAll<'foobarfoobar', 'ob', 'b'>, 'fobarfobar'>>,
  Expect<Equal<ReplaceAll<'foboorfoboar', 'bo', 'b'>, 'foborfobar'>>,
  Expect<Equal<ReplaceAll<'', '', ''>, ''>>,
]