Swift Unit Testing: Checking for equality of two objects of the same class

Question

How would you create a test function to compare the contents of two objects of the same class?

Background: I have a function which extracts data from a CSV file and uses that data to create an object. I want to know if this function is generating the correct output.

score 3 · Accepted Answer · answered Feb 20 '19 at 03:55

3

Look at Equatable protocol. E.g.

extension MyClass: Equatable
{
  static func ==(lhs: MyClass, rhs: MyClass) -> Bool
  {
    return (lhs.property1 == rhs.property1) && (lhs.allData == rhs.allData)
  }
}

answered Feb 20 '19 at 03:55

Chris Shaw

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Oh, I see. So I would need to create a logical check to compare each member variable? – infinite369 Feb 20 '19 at 04:31
Yes. Depending on your class definition, this may need to compare contents of members as well as the value of members (look-up deep compare, or deep equality). E.g. if allData in my example is another class, you may need to implement further Equatable implementations. – Chris Shaw Feb 20 '19 at 04:38
Thank you, I will look into the topics you mentioned. – infinite369 Feb 20 '19 at 05:13

Jay · Answer 2 · 2019-02-20T22:19:41.800

-1

Did you just wanted to check for class kind, like below? similar to [custom isKindOfClass: MyClass]

guard customClass is MyClass else {
        XCTFail("FAILURE ")
        return 
    }

Edit:

Compare contents of two custom objects, check this. After implementing the custom equatable method, use the below statement to check the unit test.

XCTAssert(object1 == object2)

edited Feb 20 '19 at 22:19

answered Feb 20 '19 at 04:11

Jay

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OP asked for `compare the contents of two objects of the same class`. – Ratul Sharker Feb 20 '19 at 04:17
1

`===` operator checks for reference of the object instead of the contents. – Ratul Sharker Feb 20 '19 at 04:44
i mean, you need to compare the contents using the link provided(`static func ==(lhs:rhs)-> Bool`) and then compare using the `==` in your unit tests. – Jay Feb 20 '19 at 22:16

Swift Unit Testing: Checking for equality of two objects of the same class

2 Answers2