XCTAssertEquals with two dicts in Swift

Question

I am doing the exercism.io programming exercises and the tests I have to perform on my code has the goal to compare to dicts with each other. The sourcecode of the exercise can be found here https://github.com/exercism/xswift/tree/master/word-count

As of what I have understood bridgeToObjectiveC is apples internal methods for doing things and therefore they have been removed. With them i get '[S : T]' does not have a member named 'bridgeToObjectiveC' which is very understandable if they have removed it.

Without the method using only the params in the AssertEquals call i get '[S : T]' does not conform to protocol 'Equatable'. Is two dicts not comparable in Swift? How would I do to get them comparable?

Answer 1

No, Swift dictionaries are not directly comparable. For the purposes of unit-testing, you can either do manual comparisons of their sizes and pair-wise element comparisons, or you can do the easy thing and create NSDictionarys out of them and compare them that way.

Answer 2

Try

XCTAssertEqual(swiftDict as NSObject, objCDict as NSObject)

Forces the compiler to just chill out and call the isEqual: method on both.

Answer 3

You can check equality of dictionaries as long as the values are Equatable. Modify XCTAssertEqualDictionaries to include a generic constraint:

func XCTAssertEqualDictionaries<S, T: Equatable>(first: [S:T], _ second: [S:T]) {
    XCTAssert(first == second)
}