Method alpha

src/modules/string/index.ts:173–247

* Generating a string consisting of letters in the English alphabet. * * @param options Either the length of the string to generate or the optional options object. * @param options.length The length of the string to generate either as a fixed length or as a length range. Defaults to `1`.

(
    options:
      | number
      | {
          /**
           * The length of the string to generate either as a fixed length or as a length range.
           *
           * @default 1
           */
          length?:
            | number
            | {
                /**
                 * The minimum length of the string to generate.
                 */
                min: number;
                /**
                 * The maximum length of the string to generate.
                 */
                max: number;
              };
          /**
           * The casing of the characters.
           *
           * @default 'mixed'
           */
          casing?: Casing;
          /**
           * An array with characters which should be excluded in the generated string.
           *
           * @default []
           */
          exclude?: ReadonlyArray<LiteralUnion<AlphaChar>> | string;
        } = {}
  )

   * @since 8.0.0
   */
  alpha(
    options:
      | number
      | {
          /**
           * The length of the string to generate either as a fixed length or as a length range.
           *
           * @default 1
           */
          length?:
            | number
            | {
                /**
                 * The minimum length of the string to generate.
                 */
                min: number;
                /**
                 * The maximum length of the string to generate.
                 */
                max: number;
              };
          /**
           * The casing of the characters.
           *
           * @default 'mixed'
           */
          casing?: Casing;
          /**
           * An array with characters which should be excluded in the generated string.
           *
           * @default []
           */
          exclude?: ReadonlyArray<LiteralUnion<AlphaChar>> | string;
        } = {}
  ): string {
    if (typeof options === 'number') {
      options = {
        length: options,
      };
    }

    const length = this.faker.helpers.rangeToNumber(options.length ?? 1);
    if (length <= 0) {
      return '';
    }

    const { casing = 'mixed' } = options;
    let { exclude = [] } = options;

    if (typeof exclude === 'string') {
      exclude = [...exclude];
    }

    let charsArray: string[];
    switch (casing) {
      case 'upper': {
        charsArray = [...UPPER_CHARS];
        break;