@cuppachino/type-space/dist/strings/string-includes.d.ts

A collection of type utilities for TypeScript.

import type { Assert } from '../assert';
import type { Chars } from './chars';
import type { IndexOf } from '../index-of';
import type { NumberLike } from '../number-like';
import type { SplitAt } from './split-at';
/**
 * Check if a string literal includes another string literal, inclusive (⊆).
 *
 * @example
 * ```
 * type _StringIncludes_Cases = [
 * 	ExpectTrue<StringIncludes<'abc', 'a'>>,
 * 	ExpectTrue<StringIncludes<'abc', 'bc'>>,
 * 	ExpectTrue<StringIncludes<'abc', 'abc'>>,
 * 	ExpectFalse<StringIncludes<'NOT', 'NOT-INCLUDE'>>,
 * 	//
 * 	ExpectTrue<StringIncludes<'abc', '', 0>>,
 * 	ExpectTrue<StringIncludes<'abc', '', '0'>>,
 * 	ExpectTrue<StringIncludes<'abc', 'a', '0'>>,
 * 	ExpectTrue<StringIncludes<'abc', 'abc', '0'>>,
 * 	ExpectFalse<StringIncludes<'NOT', 'NOT-INCLUDE', '0'>>,
 * 	//
 * 	ExpectTrue<StringIncludes<'abc', 'b', 1>>,
 * 	ExpectTrue<StringIncludes<'abc', 'bc', '1'>>,
 * 	ExpectFalse<StringIncludes<'abc', 'a', '1'>>,
 * 	ExpectFalse<StringIncludes<'abc', 'ab', '1'>>,
 * 	ExpectFalse<StringIncludes<'NOT', 'NOT-INCLUDE', '1'>>,
 * 	//
 * 	ExpectTrue<StringIncludes<'abc', 'c', 2>>,
 * 	ExpectTrue<StringIncludes<'abc', 'c', '2'>>,
 * 	ExpectFalse<StringIncludes<'abc', 'a', '2'>>,
 * 	ExpectFalse<StringIncludes<'abc', 'ab', '2'>>,
 * 	ExpectFalse<StringIncludes<'abc', 'abc', '2'>>,
 * 	ExpectFalse<StringIncludes<'NOT', 'NOT-INCLUDE', '2'>>
 * ]
 * ```
 */
export type StringIncludes<S extends string, Search extends string, I extends NumberLike<IndexOf<Chars<S>>> = Assert<0, NumberLike<IndexOf<Chars<S>>>>> = SplitAt<S, I> extends [infer _A, infer B] ? B extends `${infer _A}${Search}${infer _B}` ? true : false : never;