Sample iOS Unit Tests: Confirming that a NSManagedObject subclass Category properly seeds CoreData

Sample iOS Unit Tests: Confirming that a NSManagedObject subclass Category properly seeds CoreData

#import <UIKit/UIKit.h>
#import <XCTest/XCTest.h>
#import "AppDelegate.h"
#import "Item.h"
#import "Item+CoreData.h" //note: Item+CoreData is a category for the Item entity (i.e. NSManagedObject subclass)

@interface Item_CoreDataTest : XCTestCase

//for accessing CoreData NSManagedObjectContext in assertions
@property (nonatomic, strong) AppDelegate *appDelegate;
@property (nonatomic, strong) NSManagedObjectContext *managedObjectContext;

@end

@implementation Item_CoreDataTest

- (void)setUp {
    
    [super setUp];
    
    //for accessing CoreData NSManagedObjectContext
    self.appDelegate = [[UIApplication sharedApplication] delegate];
    self.managedObjectContext = [self.appDelegate managedObjectContext];
    
    //execute class method for seeding CoreData with Item entities (i.e. NSManagedObject subclass instances)
    [Item insertItemDataFromPlist:@"ItemSeed" inManagedObjectContext:self.managedObjectContext];
}

- (void)tearDown {
    
    self.managedObjectContext = nil;
    
    self.appDelegate = nil;
    
    [super tearDown];
}

- (void)testEntityCategorySeededCoreData {
    
    NSArray *itemsInCoreData = [Item fetchItemsInManagedObjectContext:self.managedObjectContext];
    
    XCTAssertNotNil(itemsInCoreData, @"Model category under test fails to seed CoreData with Item entities");
    
    XCTAssert([itemsInCoreData count] > 0, @"Model category under test fails to seed CoreData with Item entities");
}

- (void)testEntityCategorySeededCoreDataWithItemsProperlyAttributed {
    
    NSArray *itemsInCoreData = [Item fetchItemsInManagedObjectContext:self.managedObjectContext];
    
    Item *sampleItem = [itemsInCoreData lastObject];
    
    XCTAssert([sampleItem isKindOfClass:[Item class]], @"Model category under test seeded CoreData, but entity is not of type Item");
    
    XCTAssert([sampleItem.name length] > 0, @"Model category under test seeded CoreData, but entity does not have a name property assigned");
}

@end