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 complex objects. Objects having functions or the File class (from input type file), it just can't. How to overcome this?

Answer 1

Try the Underscore _.isEqual() function:

expect(_.isEqual(obj1, obj2)).toEqual(true);

If that works, you could create a custom matcher:

this.addMatchers({
    toDeepEqual: function(expected) {
        return _.isEqual(this.actual, expected);
    };
});

You can then write specs like the following:

expect(some_obj).toDeepEqual(expected_obj);

Answer 2

As Vlad Magdalin pointed out in the comments, making the object to a JSON string, it can be as deep as it is, and functions and File/FileList class. Of course, instead of toString() on the function, it could just be called 'Function'

function replacer(k, v) {
    if (typeof v === 'function') {
        v = v.toString();
    } else if (window['File'] && v instanceof File) {
        v = '[File]';
    } else if (window['FileList'] && v instanceof FileList) {
        v = '[FileList]';
    }
    return v;
}

beforeEach(function(){
    this.addMatchers({
        toBeJsonEqual: function(expected){
            var one = JSON.stringify(this.actual, replacer).replace(/(\\t|\\n)/g,''),
                two = JSON.stringify(expected, replacer).replace(/(\\t|\\n)/g,'');

                return one === two;
            }
    });
});

expect(obj).toBeJsonEqual(obj2);