Added userrepositorytest

Added some tests for user repository

src/test/java/NTNU/IDATT1002/repository/UserRepositoryTest.java

+package NTNU.IDATT1002.repository;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+import NTNU.IDATT1002.models.User;
+import NTNU.IDATT1002.service.UserService;
+import java.util.List;
+import java.util.Optional;
+import javax.persistence.EntityManager;
+import javax.persistence.EntityManagerFactory;
+import javax.persistence.Persistence;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+/**
+ * Test for {@link UserRepository}
+ */
+class UserRepositoryTest {
+
+  private UserRepository userRepository;
+  private String testUsername;
+  private User testUser;
+
+
+  /**
+   * Sets up necessary testdata for testin
+   */
+  @BeforeEach
+  void setUp() {
+    EntityManagerFactory entityManagerFactory = Persistence.createEntityManagerFactory("ImageApplicationTest");
+    EntityManager entityManager = entityManagerFactory.createEntityManager();
+    userRepository = new UserRepository(entityManager);
+
+    testUser = new User();
+    testUsername = "Test123";
+    testUser.setUsername(testUsername);
+  }
+
+  /**
+   * Test that save a user and makes sure the user was saved
+   */
+  @Test
+  void testSaveReturnsInstance() {
+    Optional<User> savedUser = userRepository.save(testUser);
+
+    assertTrue(savedUser.isPresent());
+    assertEquals(testUsername, savedUser.get().getUsername());
+  }
+
+  /**
+   * Test that tries to save user with invalid entity and make sure an empty optional is returned
+   */
+  @Test
+  void testSaveInvalidEntityRetrunsEmptyOptional() {
+    Optional<User> savedUser = userRepository.save(null);
+
+    assertTrue(savedUser.isEmpty());
+  }
+
+  /**
+   * Test that saves two users and makes sure both are saved
+   */
+  @Test
+  void testFindAllReturnsAllSavedEntities() {
+    User testUser2 = new User();
+    String testUsername2 = "Test321";
+    testUser2.setUsername(testUsername2);
+
+    userRepository.save(testUser);
+    userRepository.save(testUser2);
+
+    List<?> foundUsers = userRepository.findAll();
+
+    assertEquals(2, foundUsers.size());
+  }
+
+  /**
+   * Test that saves a user and makes sure correct user is returned when searching by id
+   */
+  @Test
+  void testFindByIdReturnsOptionalWithCorrectEntity() {
+    userRepository.save(testUser);
+    Optional<User> foundUSer = userRepository.findById(testUsername);
+
+    assertTrue(foundUSer.isPresent());
+    assertEquals(testUsername, foundUSer.get().getUsername());
+  }
+
+  /**
+   * Test that deletes a saved user by id and makes sure it is deleted
+   */
+  @Test
+  void testDeleteByIdRemovesEntitiy() {
+    userRepository.save(testUser);
+    Optional<User> foundUser = userRepository.findById(testUsername);
+
+    foundUser.ifPresent(user -> userRepository.deleteById(testUsername));
+    Optional<User> deletedUser = userRepository.findById(testUsername);
+
+    assertTrue(deletedUser.isEmpty());
+  }
+
+  /**
+   * Test that deletes a saved user object and makes sure it is deleted
+   */
+  @Test
+  void testDeleteRemovesEntity() {
+    userRepository.save(testUser);
+    Optional<User> foundUser = userRepository.findById(testUsername);
+
+    foundUser.ifPresent(userRepository::delete);
+    Optional<User> deletedUser = userRepository.findById(testUsername);
+
+    assertTrue(deletedUser.isEmpty());
+  }
+}
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