Function createEnumConverter

lib/internal/webidl.js:629–646

* Creates a converter for a Web IDL enum type. * @see https://webidl.spec.whatwg.org/#es-enumeration * @param {string} name Enum identifier. * @param {string[]} values Enum values. * @returns {Converter}

(name, values)

 * @returns {Converter}
 */
function createEnumConverter(name, values) {
  const E = new SafeSet(new SafeArrayIterator(values));

  return function(V, options = kEmptyObject) {
    // Web IDL enumeration step 1: convert V with ToString.
    const S = toString(V, options);

    // Step 2: throw unless S is one of the enumeration values.
    if (!E.has(S)) {
      throw makeException(
        `'${S}' is not a valid enum value of type ${name}.`,
        makeOptions(options, options.context, 'ERR_INVALID_ARG_VALUE'));
    }

    // Step 3: return the matching enumeration value.
    return S;
  };
}

/**
 * Returns the context used when converting a dictionary member.