Spring JpaRepository using EntityGraph returns null instead of Optional - spring

Question

Calling this method:
#EntityGraph(attributePaths = "permissionGroups")
Optional<User> findOneWithPermissionGroupsByLogin(String login);
With non-exsisting user login returns null instead of Optional.of(null).
I would like to figure out what should I add in order to get an Optional resault?
more complete code:
Repository
public interface UserRepository extends JpaRepository<User, Long>
{
Optional<User> findOneByLogin(String login);
#EntityGraph(attributePaths = "permissionGroups")
Optional<User> findOneWithPermissionGroupsByLogin(String login);
}
User Entity
this is relevant user entity code
#Entity
#Table(name = "jhi_user")
#Cache(usage = CacheConcurrencyStrategy.NONSTRICT_READ_WRITE)
public class User extends AbstractAuditingEntity implements Serializable {
private static final long serialVersionUID = 1L;
#Id
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "sequenceGenerator")
#SequenceGenerator(name = "sequenceGenerator")
private Long id;
#NotNull
#Pattern(regexp = Constants.LOGIN_REGEX)
#Size(min = 1, max = 50)
#Column(length = 50, unique = true, nullable = false)
private String login;
#JsonIgnore
#ManyToMany
#JoinTable(
name = "jhi_user_authority",
joinColumns = {#JoinColumn(name = "user_id", referencedColumnName = "id")},
inverseJoinColumns = {#JoinColumn(name = "authority_name", referencedColumnName = "name")})
#Cache(usage = CacheConcurrencyStrategy.NONSTRICT_READ_WRITE)
#BatchSize(size = 20)
private Set<Authority> authorities = new HashSet<>();
#ManyToMany
#Cache(usage = CacheConcurrencyStrategy.NONSTRICT_READ_WRITE)
#JoinTable(name = "euser_permission_group",
joinColumns = #JoinColumn(name="eusers_id", referencedColumnName="id"),
inverseJoinColumns = #JoinColumn(name="permission_groups_id", referencedColumnName="id"))
private Set<PermissionGroup> permissionGroups = new HashSet<>();
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getLogin() {
return login;
}
//Lowercase the login before saving it in database
public void setLogin(String login) {
this.login = login.toLowerCase(Locale.ENGLISH);
}
public Set<Authority> getAuthorities() {
return authorities;
}
#Override
public boolean equals(Object o) {
if (this == o) {
return true;
}
if (o == null || getClass() != o.getClass()) {
return false;
}
User user = (User) o;
return login.equals(user.login);
}
#Override
public int hashCode() {
return login.hashCode();
}