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A Canonical Repository Test

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A Canonical Repository Test

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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
    public void shouldSaveAllProperties() {
        Person person = randomPerson();
        repository.save(person); // TODO: Make sure your repository flushes!
    public void shouldFindBName() {
        Person matching = randomPerson();
        Person nonMatching = randomPerson();
        matching.setName("A. Matching Person");
        nonMatching.setName("A. Random Person");

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

public class PersonTest {
    // ....
    public static Person randomPerson() {
        Person person = new Pesron();
        // 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();
    public void insertData() {
    public void shouldSaveAllProperties() {
        Order order = randomOrder(person);
        repository.save(order); // TODO: Make sure your repository flushes!

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)

(Yes, this is what some people would call an integration test. Personally, I can't be bothered with this sort of classifications)


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Published at DZone with permission of Johannes Brodwall, DZone MVB. See the original article here.

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