@Test protected void getSpanNames(TestInfo testInfo) throws Exception {
    String testSuffix = testSuffix(testInfo);
    Span span = spanBuilder(testSuffix).build();

    assertThat(names().getSpanNames(span.localServiceName()).execute())
      .isEmpty();

    accept(span);

    assertThat(names().getSpanNames(span.localServiceName() + 1).execute())
      .isEmpty();

    assertThat(names().getSpanNames(span.localServiceName()).execute())
      .contains(span.name());
  }
Ensures the service name index returns distinct results
zipkin-tests/src/main/java/zipkin2/storage/ITServiceAndSpanNames.java