| /*! |
| * Chai - addMethod utility |
| * Copyright(c) 2012-2014 Jake Luer <jake@alogicalparadox.com> |
| * MIT Licensed |
| */ |
| |
| var addLengthGuard = require('./addLengthGuard'); |
| var chai = require('../../chai'); |
| var flag = require('./flag'); |
| var proxify = require('./proxify'); |
| var transferFlags = require('./transferFlags'); |
| |
| /** |
| * ### .addMethod(ctx, name, method) |
| * |
| * Adds a method to the prototype of an object. |
| * |
| * utils.addMethod(chai.Assertion.prototype, 'foo', function (str) { |
| * var obj = utils.flag(this, 'object'); |
| * new chai.Assertion(obj).to.be.equal(str); |
| * }); |
| * |
| * Can also be accessed directly from `chai.Assertion`. |
| * |
| * chai.Assertion.addMethod('foo', fn); |
| * |
| * Then can be used as any other assertion. |
| * |
| * expect(fooStr).to.be.foo('bar'); |
| * |
| * @param {Object} ctx object to which the method is added |
| * @param {String} name of method to add |
| * @param {Function} method function to be used for name |
| * @namespace Utils |
| * @name addMethod |
| * @api public |
| */ |
| |
| module.exports = function addMethod(ctx, name, method) { |
| var methodWrapper = function () { |
| // Setting the `ssfi` flag to `methodWrapper` causes this function to be the |
| // starting point for removing implementation frames from the stack trace of |
| // a failed assertion. |
| // |
| // However, we only want to use this function as the starting point if the |
| // `lockSsfi` flag isn't set. |
| // |
| // If the `lockSsfi` flag is set, then either this assertion has been |
| // overwritten by another assertion, or this assertion is being invoked from |
| // inside of another assertion. In the first case, the `ssfi` flag has |
| // already been set by the overwriting assertion. In the second case, the |
| // `ssfi` flag has already been set by the outer assertion. |
| if (!flag(this, 'lockSsfi')) { |
| flag(this, 'ssfi', methodWrapper); |
| } |
| |
| var result = method.apply(this, arguments); |
| if (result !== undefined) |
| return result; |
| |
| var newAssertion = new chai.Assertion(); |
| transferFlags(this, newAssertion); |
| return newAssertion; |
| }; |
| |
| addLengthGuard(methodWrapper, name, false); |
| ctx[name] = proxify(methodWrapper, name); |
| }; |