class AuthorTests extends grails.test.GrailsUnitTestCase {
 
    Author author
 
    void setUp() {
        super.setUp()
 
        // in testing-plugin 0.4 you can just do "mockForConstraintsTests(Book)" instead of these two lines
        registerMetaClass(Author)
        grails.test.MockUtils.prepareForConstraintsTests(Author)
 
        author = new Author(firstName: 'Michael', lastName: 'Scott')
        assertTrue author.validate()
    }
 
    void testFirsNameConstraint() {
        author.firstName = null
        assertTrue author.validate()
    }
 
    void testLastNameConstraint() {
        author.lastName = ''
        assertFalse author.validate()
        assertEquals "blank", author.errors["lastName"]
    }
 
}