Jasmine: Testing complex types for equality

Jasmine comes with two matchers that test for equality. The first is toBe:

Copyexpect(first).toBe(second)

toBe passes when first === second. Unfortunately this is useless for non-primitive values because JavaScript is a horrible language Show archive.org snapshot .

However, Jasmine comes with another matcher toEqual:

Copyexpect(first).toEqual(second)

This matcher behaves as a human would expect for types like the following:

• Arrays
• Objects
• Nested array/object constructs
• Regular expressions
• Date objects
• NaN
• Exceptions

Custom equality matchers

You can also teach toEqual additional notions of equality Show archive.org snapshot . E.g. the following code will teach toEqual to test two jQuery collections for equality:

CopybeforeEach ->
  jasmine.addCustomEqualityTester (first, second) ->
    if first instanceof jQuery && second instanceof jQuery
      first.is(second)

Using Jasmine's equality logic in your own matchers

You can use Jasmine's built-in equality logic (plus the logic added by custom equality matchers) like this:

CopybeforeEach ->
  jasmine.addMatchers
    toEqual123Array: (util, customEqualityTesters) ->
      compare: (actual)
        pass: util.equals(actual, [1, 2, 3], customEqualityTesters)

Note how the compare method is passed two arguments util and customEqualityTesters, which are both needed to access Jasmine's equality logic.