@Test protected void getSpanNames_allReturned(TestInfo testInfo) throws Exception {
    String testSuffix = testSuffix(testInfo);
    // Assure a default store limit isn't hit by assuming if 50 are returned, all are returned
    List<Span> spans = IntStream.rangeClosed(0, 50)
      .mapToObj(i -> {
        String suffix = i < 10 ? "0" + i : String.valueOf(i);
        return spanBuilder(testSuffix).name("yak" + suffix).build();
      })
      .collect(Collectors.toList());
    accept(spans);

    assertThat(names().getSpanNames(spans.get(0).localServiceName()).execute())
      .containsExactlyInAnyOrderElementsOf(spans.stream().map(Span::name)::iterator);
  }
Ensures the service name index returns distinct results
zipkin-tests/src/main/java/zipkin2/storage/ITServiceAndSpanNames.java