[Backport 2.12] [Backport 2.x] 12073 and 12267

server/src/internalClusterTest/java/org/opensearch/search/aggregations/bucket/DateHistogramIT.java

@@ -177,9 +177,9 @@ public void setupSuiteScopeCluster() throws Exception {
                 indexDoc(2, 15, 3), // date: Feb 15, dates: Feb 15, Mar 16
                 indexDoc(3, 2, 4),  // date: Mar 2, dates: Mar 2, Apr 3
                 indexDoc(3, 15, 5), // date: Mar 15, dates: Mar 15, Apr 16
-                indexDoc(3, 23, 6)
+                indexDoc(3, 23, 6)  // date: Mar 23, dates: Mar 23, Apr 24
             )
-        ); // date: Mar 23, dates: Mar 23, Apr 24
+        );
         indexRandom(true, builders);
         ensureSearchable();
     }

server/src/internalClusterTest/java/org/opensearch/search/aggregations/bucket/FilterRewriteIT.java

@@ -0,0 +1,107 @@
+/*
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * The OpenSearch Contributors require contributions made to
+ * this file be licensed under the Apache-2.0 license or a
+ * compatible open source license.
+ */
+
+package org.opensearch.search.aggregations.bucket;
+
+import com.carrotsearch.randomizedtesting.annotations.ParametersFactory;
+
+import org.opensearch.action.index.IndexRequestBuilder;
+import org.opensearch.action.search.SearchResponse;
+import org.opensearch.common.settings.Settings;
+import org.opensearch.common.time.DateFormatter;
+import org.opensearch.index.query.QueryBuilder;
+import org.opensearch.index.query.QueryBuilders;
+import org.opensearch.search.aggregations.bucket.histogram.DateHistogramInterval;
+import org.opensearch.search.aggregations.bucket.histogram.Histogram;
+import org.opensearch.test.OpenSearchIntegTestCase;
+import org.opensearch.test.ParameterizedDynamicSettingsOpenSearchIntegTestCase;
+
+import java.time.ZoneOffset;
+import java.time.ZonedDateTime;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+import static org.opensearch.common.xcontent.XContentFactory.jsonBuilder;
+import static org.opensearch.search.SearchService.CLUSTER_CONCURRENT_SEGMENT_SEARCH_SETTING;
+import static org.opensearch.search.aggregations.AggregationBuilders.dateHistogram;
+import static org.opensearch.test.hamcrest.OpenSearchAssertions.assertAcked;
+
+@OpenSearchIntegTestCase.SuiteScopeTestCase
+public class FilterRewriteIT extends ParameterizedDynamicSettingsOpenSearchIntegTestCase {
+
+    // simulate segment level match all
+    private static final QueryBuilder QUERY = QueryBuilders.termQuery("match", true);
+    private static final Map<String, Long> expected = new HashMap<>();
+
+    public FilterRewriteIT(Settings dynamicSettings) {
+        super(dynamicSettings);
+    }
+
+    @ParametersFactory
+    public static Collection<Object[]> parameters() {
+        return Arrays.asList(
+            new Object[] { Settings.builder().put(CLUSTER_CONCURRENT_SEGMENT_SEARCH_SETTING.getKey(), false).build() },
+            new Object[] { Settings.builder().put(CLUSTER_CONCURRENT_SEGMENT_SEARCH_SETTING.getKey(), true).build() }
+        );
+    }
+
+    @Override
+    protected void setupSuiteScopeCluster() throws Exception {
+        assertAcked(client().admin().indices().prepareCreate("idx").get());
+
+        final int segmentCount = randomIntBetween(2, 10);
+        final Set<Long> longTerms = new HashSet();
+
+        final Map<String, Integer> dateTerms = new HashMap<>();
+        for (int i = 0; i < segmentCount; i++) {
+            final List<IndexRequestBuilder> indexRequests = new ArrayList<>();
+
+            long longTerm;
+            do {
+                longTerm = randomInt(segmentCount * 2);
+            } while (!longTerms.add(longTerm));
+            ZonedDateTime time = ZonedDateTime.of(2024, 1, ((int) longTerm % 20) + 1, 0, 0, 0, 0, ZoneOffset.UTC);
+            String dateTerm = DateFormatter.forPattern("yyyy-MM-dd").format(time);
+
+            final int frequency = randomBoolean() ? 1 : randomIntBetween(2, 20);
+            for (int j = 0; j < frequency; j++) {
+                indexRequests.add(
+                    client().prepareIndex("idx")
+                        .setSource(jsonBuilder().startObject().field("date", dateTerm).field("match", true).endObject())
+                );
+            }
+            expected.put(dateTerm + "T00:00:00.000Z", (long) frequency);
+
+            indexRandom(true, false, indexRequests);
+        }
+
+        ensureSearchable();
+    }
+
+    public void testMinDocCountOnDateHistogram() throws Exception {
+        final SearchResponse allResponse = client().prepareSearch("idx")
+            .setSize(0)
+            .setQuery(QUERY)
+            .addAggregation(dateHistogram("histo").field("date").dateHistogramInterval(DateHistogramInterval.DAY).minDocCount(0))
+            .get();
+
+        final Histogram allHisto = allResponse.getAggregations().get("histo");
+        Map<String, Long> results = new HashMap<>();
+        allHisto.getBuckets().forEach(bucket -> results.put(bucket.getKeyAsString(), bucket.getDocCount()));
+
+        for (Map.Entry<String, Long> entry : expected.entrySet()) {
+            assertEquals(entry.getValue(), results.get(entry.getKey()));
+        }
+    }
+}