Jasmine toEqual for complex objects (mixed with functions)
If anyone is using node.js like myself, the following method is what I use in my Jasmine tests when I am only concerned with comparing the simple properties while ignoring all functions. This method requires json-stable-stringify which is used to sort the object properties prior to serializing.
Usage:
var stringify = require('json-stable-stringify');
var obj1 = {
func: function() {
},
str1: 'str1 value',
str2: 'str2 value',
nest1: {
nest2: {
val1:'value 1',
val2:'value 2',
someOtherFunc: function() {
}
}
}
};
var obj2 = {
str2: 'str2 value',
str1: 'str1 value',
func: function() {
},
nest1: {
nest2: {
otherFunc: function() {
},
val2:'value 2',
val1:'value 1'
}
}
};
it('should compare object properties', function () {
expect(stringify(obj1)).toEqual(stringify(obj2));
});
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);
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);
Extending @Vlad Magdalin's answer, this worked in Jasmine 2:
http://jasmine.github.io/2.0/custom_matcher.html
beforeEach(function() {
jasmine.addMatchers({
toDeepEqual: function(util, customEqualityTesters) {
return {
compare: function(actual, expected) {
var result = {};
result.pass = _.isEqual(actual, expected);
return result;
}
}
}
});
});
If you're using Karma, put that in the startup callback:
callback: function() {
// Add custom Jasmine matchers.
beforeEach(function() {
jasmine.addMatchers({
toDeepEqual: function(util, customEqualityTesters) {
return {
compare: function(actual, expected) {
var result = {};
result.pass = _.isEqual(actual, expected);
return result;
}
}
}
});
});
window.__karma__.start();
});