backend/src/main/java/core/entities/User.java

@@ -103,11 +103,11 @@ public class User {
         if (this == o) return true;
         if (o == null || getClass() != o.getClass()) return false;
         User user = (User) o;
-        return Objects.equals(id, user.id) && Objects.equals(username, user.username) && Objects.equals(email, user.email) && Objects.equals(password, user.password) && Objects.equals(roles, user.roles);
+        return Objects.equals(username, user.username) && Objects.equals(email, user.email) && Objects.equals(password, user.password) && Objects.equals(roles, user.roles);
     }
 
     @Override
     public int hashCode() {
-        return Objects.hash(id, username, email, password, roles);
+        return Objects.hash(username, email, password, roles);
     }
 }

backend/src/test/java/core/users/UserRepositoryTests.java

@@ -12,6 +12,7 @@ import org.springframework.test.context.junit.jupiter.SpringExtension;
 
 import java.util.Optional;
 
+import static org.assertj.core.api.AssertionsForClassTypes.assertThat;
 import static org.junit.jupiter.api.Assertions.*;
 
 @DataJpaTest
@@ -27,11 +28,75 @@ public class UserRepositoryTests {
 
     @Test
     void test_findByUsername() {
+        //Situation 1: No user is present in the database, so no user should be found by a given username
         assertTrue(userRepository.findByUsername("FawKes100").isEmpty());
-        userRepository.save(new User(1L,"FawKes100", "mail@fawkes100.de", "123456"));
 
+        //persist a user to the database, so a user is present
+        testEntityManager.persist(new User("FawKes100", "mail@fawkes100.de", "123456"));
+
+        //Situation 2: User with name "FawKes100" is present
         Optional<User> findResult = userRepository.findByUsername("FawKes100");
         assertTrue(findResult.isPresent());
-        assertEquals(new User(1L, "FawKes100", "mail@fawkes100.de", "123456"),findResult.get());
+        assertEquals(new User("FawKes100", "mail@fawkes100.de", "123456"),findResult.get());
+
+        //Situation 3: No user with the required name is present
+        findResult = userRepository.findByUsername("fawkes1001");
+        assertFalse(findResult.isPresent());
     }
+
+    @Test
+    void test_existsByMail() {
+        //Situation 1: invalid email format should not matter
+        assertFalse(userRepository.existsByEmail("FawKes100"));
+
+        //Situation 2: No user exists with such a mail
+        assertFalse(userRepository.existsByEmail("mail@fawkes100.de"));
+
+        //persist a user to the database, so a user is present
+        testEntityManager.persist(new User("FawKes100", "mail@fawkes100.de", "123456"));
+
+        //Situation 3: User with this mail exists
+        assertTrue(userRepository.existsByEmail("mail@fawkes100.de"));
+
+        //Situation 4: No user exists with such a mail (non-empty db)
+        assertFalse(userRepository.existsByEmail("mail2@fawkes100.de"));
+    }
+
+    @Test
+    void test_existsByUsername() {
+        //Situation 1: Empty database
+        assertFalse(userRepository.existsByUsername("FawKes100"));
+
+        //persist a user to the database, so a user is present
+        testEntityManager.persist(new User("FawKes100", "mail@fawkes100.de", "123456"));
+
+        //Situation 3: User with this name exists
+        assertTrue(userRepository.existsByUsername("FawKes100"));
+
+        //Situation 4: No user exists with such a mail (non-empty db)
+        assertFalse(userRepository.existsByUsername("FawKes101"));
+    }
+
+    @Test
+    void test_deleteUserByName() {
+        //persist a user to the database, so a user is present
+        User user = testEntityManager.persist(new User("FawKes100", "mail@fawkes100.de", "123456"));
+        User user1 = testEntityManager.persist(new User("FawKes101", "mail@fawkes101.de", "123456"));
+
+        userRepository.deleteByUsername("FawKes100");
+
+        assertThat(testEntityManager.find(User.class, user.getId())).isNull();
+        assertThat(testEntityManager.find(User.class, user1.getId())).isNotNull();
+    }
+
+
+    @Test
+    void test_countUsers() {
+        assertEquals(0, userRepository.countUsers());
+
+        testEntityManager.persist(new User("FawKes100", "mail@fawkes100.de", "123456"));
+        assertEquals(1, userRepository.countUsers());
+
+    }
+
 }