chai/lib/chai/utils/transferFlags.js

BDD/TDD assertion library for node.js and the browser. Test framework agnostic.

/*!
 * Chai - transferFlags utility
 * Copyright(c) 2012-2014 Jake Luer <jake@alogicalparadox.com>
 * MIT Licensed
 */

/**
 * ### .transferFlags(assertion, object, includeAll = true)
 *
 * Transfer all the flags for `assertion` to `object`. If
 * `includeAll` is set to `false`, then the base Chai
 * assertion flags (namely `object`, `ssfi`, `lockSsfi`,
 * and `message`) will not be transferred.
 *
 *     var newAssertion = new Assertion();
 *     utils.transferFlags(assertion, newAssertion);
 *
 *     var anotherAssertion = new Assertion(myObj);
 *     utils.transferFlags(assertion, anotherAssertion, false);
 *
 * @param {import('../assertion.js').Assertion} assertion the assertion to transfer the flags from
 * @param {object} object the object to transfer the flags to; usually a new assertion
 * @param {boolean} includeAll
 * @namespace Utils
 * @name transferFlags
 * @private
 */
export function transferFlags(assertion, object, includeAll) {
  let flags = assertion.__flags || (assertion.__flags = Object.create(null));

  if (!object.__flags) {
    object.__flags = Object.create(null);
  }

  includeAll = arguments.length === 3 ? includeAll : true;

  for (let flag in flags) {
    if (
      includeAll ||
      (flag !== 'object' &&
        flag !== 'ssfi' &&
        flag !== 'lockSsfi' &&
        flag != 'message')
    ) {
      object.__flags[flag] = flags[flag];
    }
  }
}