A Canonical Repository Test

There are only so many ways to test that your persistence layer is implemented correctly or that you’re using an ORM correctly. Here’s my canonical tests for a repository (Java-version):

import static org.fest.assertions.api.Assertions.*;
 
public class PersonRepositoryTest {
    private PersonRepository repository; // TODO < == you must initialize this
 
    @Test
    public void shouldSaveAllProperties() {
        Person person = randomPerson();
        repository.save(person); // TODO: Make sure your repository flushes!
        assertThat(repository.find(person.getId())
            .isNotSameAs(person)
            .isEqualTo(person)
            .isEqualsToByComparingFields(person);
    }
 
    @Test
    public void shouldFindBName() {
        Person matching = randomPerson();
        Person nonMatching = randomPerson();
        matching.setName("A. Matching Person");
        nonMatching.setName("A. Random Person");
        repository.save(matching);
        repository.save(nonMatching);
        assertThat(repository.findByNameLike("MATCH"))
            .contains(matching)
            .doesNotContain(nonMatching);
    }
}

Very simple. The randomPerson test helper generates actually random people:

public class PersonTest {
    // ....
    public static Person randomPerson() {
        Person person = new Pesron();
        person.setName(randomName());
        // TODO Initialize all properties
        return person;
    }
 
    public static String randomName() {
        return RandomData.randomWord() + " " + RandomData.randomWord() + "son";
    }
}
 
 
public class RandomData {
    public static String randomString() {
        return random("foo", "bar", "baz", "qux", "quux"); // TODO: Add more!
    }
 
    public static <T> T random(T... options) {
        return options[random(options.length)];
    }
 
    public static int random(int max) {
        return random.nextInt(max);
    }
 
    private static Random random = new Random();
}

If your data has relationships with other entities, you may want to include those as well:

public class OrderRepositoryTest {
    private OrderRepository repository; // TODO < == you must initialize this
    private PersonRepository personRepository; // TODO <== you must initialize this
 
    private Person person = PersonTest.randomPerson();
 
    @Before
    public void insertData() {
        personRepository.save(person);
    }
 
    @Test
    public void shouldSaveAllProperties() {
        Order order = randomOrder(person);
        repository.save(order); // TODO: Make sure your repository flushes!
        assertThat(repository.find(order.getId())
            .isNotSameAs(order)
            .isEqualTo(order)
            .isEqualsToByComparingFields(order);
    }

A simple and easy way to simplify your Repository testing.

(The tests use FEST assert 2 for the syntax. Look at FluentAssertions for a similar API in .NET)