Function fill

deps/undici/src/lib/web/fetch/headers.js:45–80

* @param {Headers} headers * @param {Array|Object} object

(headers, object)

 * @param {Array|Object} object
 */
function fill (headers, object) {
  // To fill a Headers object headers with a given object object, run these steps:

  // 1. If object is a sequence, then for each header in object:
  // Note: webidl conversion to array has already been done.
  if (Array.isArray(object)) {
    for (let i = 0; i < object.length; ++i) {
      const header = object[i]
      // 1. If header does not contain exactly two items, then throw a TypeError.
      if (header.length !== 2) {
        throw webidl.errors.exception({
          header: 'Headers constructor',
          message: `expected name/value pair to be length 2, found ${header.length}.`
        })
      }

      // 2. Append (header’s first item, header’s second item) to headers.
      appendHeader(headers, header[0], header[1])
    }
  } else if (typeof object === 'object' && object !== null) {
    // Note: null should throw

    // 2. Otherwise, object is a record, then for each key → value in object,
    //    append (key, value) to headers
    const keys = Object.keys(object)
    for (let i = 0; i < keys.length; ++i) {
      appendHeader(headers, keys[i], object[keys[i]])
    }
  } else {
    throw webidl.errors.conversionFailed({
      prefix: 'Headers constructor',
      argument: 'Argument 1',
      types: ['sequence<sequence<ByteString>>', 'record<ByteString, ByteString>']
    })
  }
}

/**
 * @see https://fetch.spec.whatwg.org/#concept-headers-append