svoid test_uniqCI() {
  new Concepts cc;
  Concept a = cnew(cc, Concept);
  Concept b = uniqCI(cc, Concept, myRef := a);
  assertSameVerbose(cc, a._concepts());
  assertSameVerbose(cc, b._concepts());
  assertEqualsVerbose(a, cget(b, "myRef"));
  assertEqualsVerbose(1, l(b.refs));
  assertEqualsVerbose(1, l(a.backRefs));
  assertEquals(ll(b), findBackRefs(a));
}