@Test
    public void testFlatIntoOneProfileOneProfile() {
        val profile1 = new CommonProfile();
        profile1.setId("ONE");
        val profiles = List.of(profile1);
        assertEquals(profile1, ProfileHelper.flatIntoOneProfile(profiles).get());
    }
Tests {@link ProfileHelper}.

@author Jerome Leleu
@since 1.9.0
pac4j-core/src/test/java/org/pac4j/core/profile/ProfileHelperTests.java