     }
     let context = stack.mainContext
     context.performAndWait {
-      insertSampleData(in: context)
+      context.fillWithSampleData()
       try! context.save()
     }
     

    let context = stack.mainContext
    
    context.performAndWait {
      insertSampleData(in: context)
      try! context.save()
    }
    


class NSFetchRequestResultUtilsTests: XCTestCase {
  
  func testBatchFaulting() {
    // Given
    let stack = CoreDataStack()!
    let context = stack.mainContext
    
    context.performAndWait {
      context.fillWithSampleData()
      try! context.save()
    }
    
