@Test
    public void testSegmentProximity() {
        assertMetrics("segmentProximity:1",  "a","a");
        assertMetrics("segmentProximity:0",  "a","x");
        assertMetrics("segmentProximity:1",  "a","a x");
        assertMetrics("segmentProximity:0",  "a b","a x x x x x x x x x x x x x x x x x x x x x x x b");
        assertMetrics("segmentProximity:0.4","a b","a x x x x x x x x x x x x x x x x x x x x x x b x x x x x x x x x x x x x x x x");
        assertMetrics("segmentProximity:0",  "a b c","a b x x x x x x x x x x x x x x x x x x x x x c");
        assertMetrics("segmentProximity:0.4","a b c","a b x x x x x x x x x x x x x x x x x x x x x c x x x x x x x x x x x x x x x x");
        assertMetrics("segmentProximity:0.4","a b c","b c x x x x x x x x x x x x x x x x x x x x x a x x x x x x x x x x x x x x x x");
    }
Tests exactness (using field exactness only - nothing additional of interest to test with query exactness
as that is just another number multiplied with the term exactness)
searchlib/src/test/java/com/yahoo/searchlib/ranking/features/fieldmatch/test/FieldMatchMetricsTestCase.java