Add wrapIfNested

Author: luigidellaquila

x-pack/plugin/ql/src/main/java/org/elasticsearch/xpack/ql/planner/ExpressionTranslators.java

@@ -369,7 +369,8 @@ public static Query doTranslate(Range r, TranslatorHandler handler) {
                 return handler.wrapFunctionQuery(r, r.value(), () -> translate(r, handler));
             }
             // Fall back to script query for non-foldable bounds (e.g., DATE_ADD with field reference)
-            return new ScriptQuery(r.source(), r.asScript());
+            Query q = new ScriptQuery(r.source(), r.asScript());
+            return wrapIfNested(q, r.value());
         }
 
         private static RangeQuery translate(Range r, TranslatorHandler handler) {

x-pack/plugin/ql/src/test/java/org/elasticsearch/xpack/ql/planner/ExpressionTranslatorsTests.java

@@ -0,0 +1,73 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License
+ * 2.0; you may not use this file except in compliance with the Elastic License
+ * 2.0.
+ */
+package org.elasticsearch.xpack.ql.planner;
+
+import org.elasticsearch.test.ESTestCase;
+import org.elasticsearch.xpack.ql.expression.Expression;
+import org.elasticsearch.xpack.ql.expression.FieldAttribute;
+import org.elasticsearch.xpack.ql.expression.Literal;
+import org.elasticsearch.xpack.ql.expression.predicate.Range;
+import org.elasticsearch.xpack.ql.querydsl.query.NestedQuery;
+import org.elasticsearch.xpack.ql.querydsl.query.Query;
+import org.elasticsearch.xpack.ql.querydsl.query.ScriptQuery;
+import org.elasticsearch.xpack.ql.tree.Source;
+import org.elasticsearch.xpack.ql.type.DataTypes;
+import org.elasticsearch.xpack.ql.type.EsField;
+
+import java.time.ZoneOffset;
+import java.time.ZonedDateTime;
+import java.util.Collections;
+
+import static org.hamcrest.Matchers.containsString;
+import static org.hamcrest.Matchers.instanceOf;
+
+public class ExpressionTranslatorsTests extends ESTestCase {
+
+    private static final Source SOURCE = Source.EMPTY;
+
+    public void testRangeWithNonFoldableBoundsOnNestedFieldReturnsNestedQuery() {
+        EsField nestedEsField = new EsField("nested", DataTypes.NESTED, Collections.emptyMap(), false);
+        FieldAttribute nestedParent = new FieldAttribute(SOURCE, "nested", nestedEsField);
+
+        EsField dateEsField = new EsField("date", DataTypes.DATETIME, Collections.emptyMap(), true);
+        FieldAttribute nestedDateField = new FieldAttribute(SOURCE, nestedParent, "nested.date", dateEsField);
+
+        assertTrue(nestedDateField.isNested());
+        assertEquals("nested", nestedDateField.nestedParent().name());
+
+        // Use the field itself as lower bound to make it non-foldable
+        Expression nonFoldableLower = nestedDateField;
+        Expression foldableUpper = new Literal(SOURCE, ZonedDateTime.now(ZoneOffset.UTC), DataTypes.DATETIME);
+
+        Range range = new Range(SOURCE, nestedDateField, nonFoldableLower, true, foldableUpper, true, ZoneOffset.UTC);
+        assertFalse(range.lower().foldable());
+        assertTrue(range.upper().foldable());
+
+        Query result = ExpressionTranslators.Ranges.doTranslate(range, new QlTranslatorHandler());
+
+        assertThat(result, instanceOf(NestedQuery.class));
+        String queryString = result.asBuilder().toString();
+        assertThat(queryString, containsString("\"nested\""));
+        assertThat(queryString, containsString("\"script\""));
+    }
+
+    public void testRangeWithNonFoldableBoundsOnNonNestedFieldReturnsScriptQuery() {
+        EsField dateEsField = new EsField("date", DataTypes.DATETIME, Collections.emptyMap(), true);
+        FieldAttribute dateField = new FieldAttribute(SOURCE, "date", dateEsField);
+
+        assertFalse(dateField.isNested());
+
+        Expression nonFoldableLower = dateField;
+        Expression foldableUpper = new Literal(SOURCE, ZonedDateTime.now(ZoneOffset.UTC), DataTypes.DATETIME);
+
+        Range range = new Range(SOURCE, dateField, nonFoldableLower, true, foldableUpper, true, ZoneOffset.UTC);
+
+        Query result = ExpressionTranslators.Ranges.doTranslate(range, new QlTranslatorHandler());
+
+        assertThat(result, instanceOf(ScriptQuery.class));
+    }
+}