AliasUtilTest.testThatAliasCannotBeReparented()

/*
 * See what happens when you attempt to reparent a child record through a
 * Master-Detail field that is <em>not</em> configured to allow such
 * reparenting.
 *
 * This code was last run in a Winter '14 org.
 *
 * @version 0.1
 * @author  Marty Chang (Slalom Consulting)
 */
@isTest
private class AliasUtilTest {

    /*
     * Attempt to reparent an alias. You will see that this is silently futile,
     * if child records are not allowed to be reparented.
     */
    public static testMethod void testThatAliasCannotBeReparented() {

        // Set up the test records

        Account acme = new Account(Name = 'Acme ApexTest Corporation');
        Account zenith = new Account(Name = 'Zenith ApexTest Corporation');

        insert new List<Account> { acme, zenith };

        Alias__c zen = new Alias__c(Name = 'Zen', Account__c = zenith.Id);

        insert zen;

        // Start the test

        Test.startTest();

        // Attempt to reparent the alias

        update new Alias__c(Id = zen.Id, Account__c = acme.Id);

        // Stop the test

        Test.stopTest();

        // Retrieve the alias as it now exists in the database.
        // What will the Account value be?

        List<Alias__c> matchedAliases = [
            SELECT Id, Account__c
            FROM Alias__c
            WHERE Id = :zen.Id
        ];

        System.assertEquals(zenith.Id, matchedAliases.get(0).Account__c,
            'The Account value should not have changed, ' +
                'if the Account field cannot be reparented');
    }
}