Sample on how you can easily test your memory management in Swift

TestingMemoryManagement.swift

class Cache<T> {
    private lazy var objects = [String : T]()
    
    func object(forKey key: String) -> T? {
        return objects[key]
    }
    
    func addObject(_ object: T, forKey key: String) {
        objects[key] = object
    }
    
    func removeObject(forKey key: String) {
        objects[key] = nil
    }
}


class CacheTests: XCTestCase {
    func testRemovedObjectsNotRetained() {
        class Object {}
        
        // Create two variables for our object, one strong and one weak
        var object: Object? = Object()
        weak var weakObject = object
        
        let cache = Cache<Object>()
        
        // Add object to cache, and make sure the cache contains it
        cache.addObject(object!, forKey: "key")
        XCTAssertTrue(cache.object(forKey: "key") === object)
        
        // Remove the object from the cache, since we have a local strong reference the weak reference should not be nil
        cache.removeObject(forKey: "key")
        XCTAssertNotNil(weakObject)
        
        // Finally, nil out the strong reference, which should release the object, making the weak reference become nil
        object = nil
        XCTAssertNil(weakObject)
    }
}

We are testing the memory mangagment of Object, right?

Just curious, what is the purpose of lines 26 > 34 ? Why not skip the caching step ?