I have a small problem. I'm trying to run the code snipper provided in the TrailHead for apex testing on "Creating TEst Data for Apex Tests" and my test code fails two test cases out 4. Here what my test runs results.



Here what the code looks like:

@isTest
private class TestAccountDeletion {

    @isTest static void TestDeleteAccountWithOneOpportunity() {
        // Test data setup
        // Create one account with one opportunity by calling a utility method
        Account[] accts = TestDataFactory.createAccountsWithOpps(1,1);
        
        // Perform test
        Test.startTest();
        Database.DeleteResult result = Database.delete(accts[0], false);
        Test.stopTest();

        // Verify that the deletion should have been stopped by the trigger,
        // so check that we got back an error.
        System.assert(!result.isSuccess());
        System.assert(result.getErrors().size() > 0);
        System.assertEquals('Cannot delete account with related opportunities.',
                             result.getErrors()[0].getMessage());
    }
    
    @isTest static void TestDeleteAccountWithNoOpportunities() {
        // Test data setup
        // Create one account with no opportunities by calling a utility method
        Account[] accts = TestDataFactory.createAccountsWithOpps(1,0);
        
        // Perform test
        Test.startTest();
        Database.DeleteResult result = Database.delete(accts[0], false);
        Test.stopTest();

        // Verify that the deletion was successful
        System.assert(result.isSuccess());
    }
    
    @isTest static void TestDeleteBulkAccountsWithOneOpportunity() {
        // Test data setup
        // Create accounts with one opportunity each by calling a utility method
        Account[] accts = TestDataFactory.createAccountsWithOpps(200,1);
        
        // Perform test
        Test.startTest();
        Database.DeleteResult[] results = Database.delete(accts, false);
        Test.stopTest();

        // Verify for each record.
        // In this case the deletion should have been stopped by the trigger,
        // so check that we got back an error.
        for(Database.DeleteResult dr : results) {
            System.assert(!dr.isSuccess());
            System.assert(dr.getErrors().size() > 0);
            System.assertEquals('Cannot delete account with related opportunities.',
                                 dr.getErrors()[0].getMessage());
        }
    }
    
    @isTest static void TestDeleteBulkAccountsWithNoOpportunities() {
        // Test data setup
        // Create accounts with no opportunities by calling a utility method
        Account[] accts = TestDataFactory.createAccountsWithOpps(200,0);
        
        // Perform test
        Test.startTest();
        Database.DeleteResult[] results = Database.delete(accts, false);
        Test.stopTest();

        // For each record, verify that the deletion was successful
        for(Database.DeleteResult dr : results) {
            System.assert(dr.isSuccess());
        }
    }
}

Any help much appreciated.