Aggregations/HL Rest client fix: missing scores (#32774)

Significance score doubles were being parsed as long. Existing tests did not catch this because SignificantLongTermsTests and SignificantStringTermsTests did not set the score. Fixed these and also added integration test.

Thanks for the report/fix, Blakko

Closes #32770

client/rest-high-level/src/test/java/org/elasticsearch/client/SearchIT.java

@@ -59,6 +59,9 @@
 import org.elasticsearch.search.aggregations.BucketOrder;
 import org.elasticsearch.search.aggregations.bucket.range.Range;
 import org.elasticsearch.search.aggregations.bucket.range.RangeAggregationBuilder;
+import org.elasticsearch.search.aggregations.bucket.significant.SignificantTerms;
+import org.elasticsearch.search.aggregations.bucket.significant.SignificantTermsAggregationBuilder;
+import org.elasticsearch.search.aggregations.bucket.significant.heuristics.PercentageScore;
 import org.elasticsearch.search.aggregations.bucket.terms.Terms;
 import org.elasticsearch.search.aggregations.bucket.terms.TermsAggregationBuilder;
 import org.elasticsearch.search.aggregations.matrix.stats.MatrixStats;
@@ -269,6 +272,33 @@ public void testSearchWithTermsAgg() throws IOException {
         assertEquals(2, type2.getDocCount());
         assertEquals(0, type2.getAggregations().asList().size());
     }
+
+    public void testSearchWithSignificantTermsAgg() throws IOException {
+        SearchRequest searchRequest = new SearchRequest();
+        SearchSourceBuilder searchSourceBuilder = new SearchSourceBuilder();
+        searchSourceBuilder.query(new MatchQueryBuilder("num","50"));
+        searchSourceBuilder.aggregation(new SignificantTermsAggregationBuilder("agg1", ValueType.STRING)
+                .field("type.keyword")
+                .minDocCount(1)
+                .significanceHeuristic(new PercentageScore()));
+        searchSourceBuilder.size(0);
+        searchRequest.source(searchSourceBuilder);
+        SearchResponse searchResponse = execute(searchRequest, highLevelClient()::search, highLevelClient()::searchAsync);
+        assertSearchHeader(searchResponse);
+        assertNull(searchResponse.getSuggest());
+        assertEquals(Collections.emptyMap(), searchResponse.getProfileResults());
+        assertEquals(0, searchResponse.getHits().getHits().length);
+        assertEquals(0f, searchResponse.getHits().getMaxScore(), 0f);
+        SignificantTerms significantTermsAgg = searchResponse.getAggregations().get("agg1");
+        assertEquals("agg1", significantTermsAgg.getName());
+        assertEquals(1, significantTermsAgg.getBuckets().size());
+        SignificantTerms.Bucket type1 = significantTermsAgg.getBucketByKey("type1");
+        assertEquals(1, type1.getDocCount());
+        assertEquals(1, type1.getSubsetDf());
+        assertEquals(1, type1.getSubsetSize());
+        assertEquals(3, type1.getSupersetDf());
+        assertEquals(1d/3d, type1.getSignificanceScore(), 0d);
+    }    
 
     public void testSearchWithRangeAgg() throws IOException {
         {

server/src/main/java/org/elasticsearch/search/aggregations/bucket/significant/ParsedSignificantTerms.java

@@ -175,7 +175,7 @@ static <B extends ParsedBucket> B parseSignificantTermsBucketXContent(final XCon
                         bucket.subsetDf = value;
                         bucket.setDocCount(value);
                     } else if (InternalSignificantTerms.SCORE.equals(currentFieldName)) {
-                        bucket.score = parser.longValue();
+                        bucket.score = parser.doubleValue();
                     } else if (InternalSignificantTerms.BG_COUNT.equals(currentFieldName)) {
                         bucket.supersetDf = parser.longValue();
                     }

server/src/test/java/org/elasticsearch/search/aggregations/bucket/significant/SignificantLongTermsTests.java

@@ -57,7 +57,10 @@ protected InternalSignificantTerms createTestInstance(String name,
         Set<Long> terms = new HashSet<>();
         for (int i = 0; i < numBuckets; ++i) {
             long term = randomValueOtherThanMany(l -> terms.add(l) == false, random()::nextLong);
-            buckets.add(new SignificantLongTerms.Bucket(subsetDfs[i], subsetSize, supersetDfs[i], supersetSize, term, aggs, format));
+            SignificantLongTerms.Bucket bucket = new SignificantLongTerms.Bucket(subsetDfs[i], subsetSize, 
+                    supersetDfs[i], supersetSize, term, aggs, format);
+            bucket.updateScore(significanceHeuristic);
+            buckets.add(bucket);
         }
         return new SignificantLongTerms(name, requiredSize, 1L, pipelineAggregators, metaData, format, subsetSize,
                 supersetSize, significanceHeuristic, buckets);

server/src/test/java/org/elasticsearch/search/aggregations/bucket/significant/SignificantStringTermsTests.java

@@ -50,7 +50,10 @@ protected InternalSignificantTerms createTestInstance(String name,
         Set<BytesRef> terms = new HashSet<>();
         for (int i = 0; i < numBuckets; ++i) {
             BytesRef term = randomValueOtherThanMany(b -> terms.add(b) == false, () -> new BytesRef(randomAlphaOfLength(10)));
-            buckets.add(new SignificantStringTerms.Bucket(term, subsetDfs[i], subsetSize, supersetDfs[i], supersetSize, aggs, format));
+            SignificantStringTerms.Bucket bucket = new SignificantStringTerms.Bucket(term, subsetDfs[i], subsetSize, 
+                    supersetDfs[i], supersetSize, aggs, format);
+            bucket.updateScore(significanceHeuristic);
+            buckets.add(bucket);
         }
         return new SignificantStringTerms(name, requiredSize, 1L, pipelineAggregators, metaData, format, subsetSize,
                 supersetSize, significanceHeuristic, buckets);