相关疑难解决方法(0)

好的,这是我的测试类中的代码:

 - (NSManagedObjectContext*)managedObjectContextWithConcurrencyType:(NSManagedObjectContextConcurrencyType)concurrencyType {
    NSManagedObjectModel *mom = [NSManagedObjectModel mergedModelFromBundles:nil];
    STAssertNotNil(mom, @"Can not create MOM from main bundle");

    NSPersistentStoreCoordinator *psc = [[NSPersistentStoreCoordinator alloc] initWithManagedObjectModel:mom];
    STAssertNotNil(psc, @"Can not create persistent store coordinator");
    NSPersistentStore *store = [psc addPersistentStoreWithType:NSInMemoryStoreType configuration:nil URL:nil options:nil error:0];
    STAssertNotNil(store, @"Can not create In-Memory persistent store");

    NSManagedObjectContext *moc = [[NSManagedObjectContext alloc] initWithConcurrencyType:concurrencyType];
    moc.persistentStoreCoordinator = psc;

    return moc;
}

这是尝试在测试方法中使用该方法时的失败消息:

Undefined symbols for architecture i386:
  "_NSInMemoryStoreType", referenced from:
      -[CrosswordItemTests managedObjectContextWithConcurrencyType:] in CrosswordItemTests.o
  "_OBJC_CLASS_$_NSEntityDescription", referenced from:
      objc-class-ref in CrosswordItemTests.o
      "_OBJC_CLASS_$_NSManagedObjectContext", referenced from: …