Fix hash code for AliasFilter

This commit fixes the hash code for AliasFilter as the previous
implementation was neglecting to take into consideration the fact that
the aliases field is an array and thus a deep hash code of it should be
computed rather than a shallow hash code on the reference.

Relates #24286

core/src/main/java/org/elasticsearch/search/internal/AliasFilter.java

@@ -126,7 +126,7 @@ public final class AliasFilter implements Writeable {
 
     @Override
     public int hashCode() {
-        return Objects.hash(aliases, filter, reparseAliases);
+        return Objects.hash(reparseAliases, Arrays.hashCode(aliases), filter);
     }
 
     @Override

core/src/test/java/org/elasticsearch/search/internal/AliasFilterTests.java

@@ -0,0 +1,62 @@
+/*
+ * Licensed to Elasticsearch under one or more contributor
+ * license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright
+ * ownership. Elasticsearch licenses this file to you under
+ * the Apache License, Version 2.0 (the "License"); you may
+ * not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+package org.elasticsearch.search.internal;
+
+import org.elasticsearch.common.io.stream.BytesStreamOutput;
+import org.elasticsearch.index.query.QueryBuilder;
+import org.elasticsearch.index.query.QueryBuilders;
+import org.elasticsearch.index.query.TermQueryBuilder;
+import org.elasticsearch.test.ESTestCase;
+import org.elasticsearch.test.EqualsHashCodeTestUtils;
+
+import java.util.Arrays;
+
+import static org.hamcrest.Matchers.greaterThan;
+import static org.hamcrest.Matchers.instanceOf;
+
+public class AliasFilterTests extends ESTestCase {
+
+    public void testEqualsAndHashCode() {
+        final QueryBuilder filter = QueryBuilders.termQuery("field", "value");
+        final String[] aliases = new String[] { "alias_0", "alias_1" };
+        final AliasFilter aliasFilter = new AliasFilter(filter, aliases);
+        final EqualsHashCodeTestUtils.CopyFunction<AliasFilter> aliasFilterCopyFunction = x -> {
+            assertThat(x.getQueryBuilder(), instanceOf(TermQueryBuilder.class));
+            final BytesStreamOutput out = new BytesStreamOutput();
+            x.getQueryBuilder().writeTo(out);
+            final QueryBuilder otherFilter = new TermQueryBuilder(out.bytes().streamInput());
+            final String[] otherAliases = Arrays.copyOf(x.getAliases(), x.getAliases().length);
+            return new AliasFilter(otherFilter, otherAliases);
+        };
+
+        final EqualsHashCodeTestUtils.MutateFunction<AliasFilter> aliasFilterMutationFunction = x -> {
+            assertThat(x.getQueryBuilder(), instanceOf(TermQueryBuilder.class));
+            final BytesStreamOutput out = new BytesStreamOutput();
+            x.getQueryBuilder().writeTo(out);
+            final QueryBuilder otherFilter = new TermQueryBuilder(out.bytes().streamInput());
+            assertThat(x.getAliases().length, greaterThan(0));
+            final String[] otherAliases = Arrays.copyOf(x.getAliases(), x.getAliases().length - 1);
+            return new AliasFilter(otherFilter, otherAliases);
+        };
+
+        EqualsHashCodeTestUtils.checkEqualsAndHashCode(aliasFilter, aliasFilterCopyFunction, aliasFilterMutationFunction);
+    }
+
+}