FRCTests.swift

import XCTest

@testable import NewApp

class FRCTests: CoreDataTestCase, NSFetchedResultsControllerDelegate {
    
    var expectedProperties: [String:AnyObject]? = nil
    var changeExpectation: XCTestExpectation?
    var deleteExpectation: XCTestExpectation?
    var insertExpectation: XCTestExpectation?
    var fetchedResultsController: NSFetchedResultsController!
    
    func updateAndWait(object: NSManagedObject, changes: [String:AnyObject]) {
        object.setValuesForKeysWithDictionary(changes)
        self.expectedProperties = changes
        self.changeExpectation = expectationWithDescription("properties are correct")
        NSLog("-- waiting for update to '\(changes)' --")
        waitForExpectationsWithTimeout(1, handler: nil)
    }

    override func setUp() {
        super.setUp()
        let request = Address.fetch(predicate: nil, sortAttribute: "messageCount", ascending: true)
        fetchedResultsController = NSFetchedResultsController(fetchRequest: request, managedObjectContext: mainContext, sectionNameKeyPath: nil, cacheName: nil)
        fetchedResultsController.delegate = self
        try! fetchedResultsController.performFetch()
    }
    
    var itemCount: Int { return self.fetchedResultsController.sections![0].numberOfObjects }
    
    func testFetchedResultsController() {

        // check counts
        XCTAssertEqual(itemCount, 0)

        // insert
        let address = Address.createEntity(inContext: mainContext) as! Address
        address.mailbox = "[email protected]"
        address.messageCount = 0
        insertExpectation = expectationWithDescription("item is inserted")
        try! mainContext.save()
        waitForExpectationsWithTimeout(1, handler: nil)
        XCTAssertEqual(itemCount, 1)
        
        // updates
        updateAndWait(address, changes: ["messageCount" : 10])
        updateAndWait(address, changes: ["messageCount" : 12])
        updateAndWait(address, changes: ["isContact" : true])
        updateAndWait(address, changes: ["messageCount" : 119])
        updateAndWait(address, changes: ["messageCount" : 103])
        updateAndWait(address, changes: ["mailbox" : "[email protected]", "isContact" : false])
        
        // delete
        deleteExpectation = expectationWithDescription("item is deleted")
        mainContext.deleteObject(address)
        waitForExpectationsWithTimeout(1, handler: nil)
        
        // check counts
        XCTAssertEqual(itemCount, 0)
    }


    func controller(controller: NSFetchedResultsController, didChangeObject anObject: AnyObject, atIndexPath indexPath: NSIndexPath?, forChangeType type: NSFetchedResultsChangeType, newIndexPath: NSIndexPath?) {
        
        switch type {
        case .Insert:
            NSLog("inserted \(anObject.objectID) at \(newIndexPath!)")
            insertExpectation?.fulfill()
            insertExpectation = nil
        case .Update, .Move:
            let expectedKeys = Array(expectedProperties!.keys)
            let actualValues = (anObject as! NSManagedObject).dictionaryWithValuesForKeys(expectedKeys) as NSDictionary
            if actualValues.isEqualToDictionary(expectedProperties!) {
                NSLog("got change: \(actualValues)")
                changeExpectation?.fulfill()
            }
        case .Delete:
            NSLog("deleted \(anObject.objectID) at \(indexPath!)")
            deleteExpectation?.fulfill()
            deleteExpectation = nil
        }
    }
    
}