string-case-conversions.ts

/**
 * Converts a label or variable name into kebab-case
 *
 * i.e
 * ```
 *  "Sentence case rekt"                  ->   "sentence-case-rekt"
 *  "Title Case Rekt"                     ->   "title-case-rekt"
 *  "camelCaseRekt"                       ->   "camel-case-rekt"
 *  "PascalCaseRekt"                      ->   "pascal-case-rekt"
 *  "snake_case_rekt"                     ->   "snake-case-rekt"
 *  "kebab-case-unchanged"                ->   "kebab-case-unchanged"
 *  "numbers2Easy4Me255Colors12thStreet"  ->   "numbers-2-easy-4-me-255-colors-12th-street"
 *  "acronymnsLikeAPIAndUIAreSeparated"   ->   "acronymns-like-api-and-ui-are-separated"
 * ```
 */
export function convertToKebabCase(name: string) {
  return name
    .replace(/\W+/g, '-') //                     guarantee any spaces are kebab'd
    .replace(/([a-z])([^-a-z])/g, '$1-$2') //    guarantee words suffixed with -
    .replace(/[-]*([A-Z])([a-z])/g, '-$1$2') //  guarantee words prefixed with -
    .replace(/^-|[_]/g, '') //                   remove duplicates / other delimiters
    .toLowerCase()
}

/**
 * Converts a label or variable name to Title Case
 *
 * i.e
 * ```
 *  "Sentence case rekt"                  ->   "Sentence Case Rekt"
 *  "Title Case Unchanged"                ->   "Title Case Unchanged"
 *  "camelCaseRekt"                       ->   "Camel Case Rekt"
 *  "PascalCaseRekt"                      ->   "Pascal Case Rekt"
 *  "snake_case_rekt"                     ->   "Snake Case Rekt"
 *  "kebab-case-unchanged"                ->   "Kebab Case Unchanged"
 *  "numbers2Easy4Me255Colors12thStreet"  ->   "Numbers 2 Easy 4 Me 255 Colors 12th Street"
 *  "acronymnsLikeAPIAndUIAreSeparated"   ->   "Acronymns Like API And UI Are Separated"
 * ```
 */
export function convertToTitleCase(name: string) {
  return name
    .replace(/([a-z])([^a-z])/g, '$1 $2') //  guarantee words are suffixed with a space
    .replace(/([A-Z])([^A-Z])/g, ' $1$2') //  guarantee words are prefixed with a space
    .trim() //                                trim excess spacing on ends
    .replace(/[\s-_]+/g, ' ') //              replace all spacing / delimiters with a single space
    .split(' ') //                            split into words
    .map((token) => token.split('')) //       split each word into letters
    .map(
      ([first, ...rest]) =>
        [
          first.toUpperCase(), //   capitalize first letter
          ...rest, //               spread remaining letters
        ].join(''), //              merge letters back into words
    )
    .join(' ') //                   merge words into sentence
}