Jasmine toEqual for complex objects (mixed with functions)

Question

Currently, I have a function that sometimes return an object with some functions inside. When using expect(...).toEqual({...}) it doesn\'t seem to match those c

Answer 1

here's how I did it using the Jasmine 2 syntax.

I created a customMatchers module in ../support/customMatchers.js (I like making modules).

"use strict";

/**
 *  Custom Jasmine matchers to make unit testing easier.
 */
module.exports = {
  // compare two functions.
  toBeTheSameFunctionAs: function(util, customEqualityTesters) {
    let preProcess = function(func) {
      return JSON.stringify(func.toString()).replace(/(\\t|\\n)/g,'');
    };

    return {
      compare: function(actual, expected) {
        return {
          pass: (preProcess(actual) === preProcess(expected)),
          message: 'The functions were not the same'
        };
      }
    };
  }
}

Which is then used in my test as follows:

"use strict";

let someExternalFunction = require('../../lib/someExternalFunction');
let thingBeingTested = require('../../lib/thingBeingTested');

let customMatchers = require('../support/customMatchers');

describe('myTests', function() {

  beforeEach(function() {
    jasmine.addMatchers(customMatchers);

    let app = {
      use: function() {}
    };

    spyOn(app, 'use');
    thingBeingTested(app);
  });

  it('calls app.use with the correct function', function() {
    expect(app.use.calls.count()).toBe(1);
    expect(app.use.calls.argsFor(0)).toBeTheSameFunctionAs(someExternalFunction);
  });

});