support map_agg in ner

fe/fe-core/src/main/java/org/apache/doris/catalog/BuiltinAggregateFunctions.java

@@ -38,6 +38,7 @@
 import org.apache.doris.nereids.trees.expressions.functions.agg.HllUnion;
 import org.apache.doris.nereids.trees.expressions.functions.agg.HllUnionAgg;
 import org.apache.doris.nereids.trees.expressions.functions.agg.IntersectCount;
+import org.apache.doris.nereids.trees.expressions.functions.agg.MapAgg;
 import org.apache.doris.nereids.trees.expressions.functions.agg.Max;
 import org.apache.doris.nereids.trees.expressions.functions.agg.MaxBy;
 import org.apache.doris.nereids.trees.expressions.functions.agg.Min;
@@ -101,6 +102,7 @@ public class BuiltinAggregateFunctions implements FunctionHelper {
             agg(HllUnion.class, "hll_raw_agg", "hll_union"),
             agg(HllUnionAgg.class, "hll_union_agg"),
             agg(IntersectCount.class, "intersect_count"),
+            agg(MapAgg.class, "map_agg"),
             agg(Max.class, "max"),
             agg(MaxBy.class, "max_by"),
             agg(Min.class, "min"),

fe/fe-core/src/main/java/org/apache/doris/nereids/trees/expressions/functions/agg/MapAgg.java

@@ -0,0 +1,92 @@
+// Licensed to the Apache Software Foundation (ASF) under one
+// or more contributor license agreements.  See the NOTICE file
+// distributed with this work for additional information
+// regarding copyright ownership.  The ASF 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.apache.doris.nereids.trees.expressions.functions.agg;
+
+import org.apache.doris.catalog.FunctionSignature;
+import org.apache.doris.nereids.trees.expressions.Expression;
+import org.apache.doris.nereids.trees.expressions.functions.ExplicitlyCastableSignature;
+import org.apache.doris.nereids.trees.expressions.shape.BinaryExpression;
+import org.apache.doris.nereids.trees.expressions.visitor.ExpressionVisitor;
+import org.apache.doris.nereids.types.MapType;
+import org.apache.doris.nereids.types.coercion.AnyDataType;
+
+import com.google.common.base.Preconditions;
+import com.google.common.collect.ImmutableList;
+import org.apache.doris.nereids.types.coercion.FollowToAnyDataType;
+
+import java.util.List;
+
+/**
+ * AggregateFunction 'map_agg'. This class is generated by GenerateFunction.
+ */
+public class MapAgg extends NullableAggregateFunction
+    implements BinaryExpression, ExplicitlyCastableSignature {
+
+    public static final List<FunctionSignature> SIGNATURES = ImmutableList.of(
+        FunctionSignature.ret(MapType.of(new FollowToAnyDataType(0), new FollowToAnyDataType(1)))
+            .args(AnyDataType.INSTANCE_WITHOUT_INDEX, AnyDataType.INSTANCE_WITHOUT_INDEX)
+    );
+
+    /**
+     * constructor with 2 arguments.
+     */
+    public MapAgg(Expression arg0, Expression arg1) {
+        this(false, false, arg0, arg1);
+    }
+
+    /**
+     * constructor with 2 arguments.
+     */
+    public MapAgg(boolean distinct, Expression arg0, Expression arg1) {
+        this(distinct, false, arg0, arg1);
+    }
+
+    private MapAgg(boolean distinct, boolean alwaysNullable, Expression arg0, Expression arg1) {
+        super("map_agg", distinct, false, arg0, arg1);
+    }
+
+    @Override
+    public FunctionSignature computeSignature(FunctionSignature signature) {
+        signature = signature.withReturnType(MapType.of(getArgumentType(0), getArgumentType(1)));
+        return super.computeSignature(signature);
+    }
+
+    /**
+     * withDistinctAndChildren.
+     */
+    @Override
+    public MapAgg withDistinctAndChildren(boolean distinct, List<Expression> children) {
+        Preconditions.checkArgument(children.size() == 2);
+        return new MapAgg(distinct, alwaysNullable, children.get(0), children.get(1));
+    }
+
+    @Override
+    public MapAgg withAlwaysNullable(boolean alwaysNullable) {
+        return new MapAgg(distinct, alwaysNullable, children.get(0), children.get(1));
+    }
+
+    @Override
+    public <R, C> R accept(ExpressionVisitor<R, C> visitor, C context) {
+        return visitor.visitMapAgg(this, context);
+    }
+
+    @Override
+    public List<FunctionSignature> getSignatures() {
+        return SIGNATURES;
+    }
+}

fe/fe-core/src/main/java/org/apache/doris/nereids/trees/expressions/visitor/AggregateFunctionVisitor.java

@@ -39,6 +39,7 @@
 import org.apache.doris.nereids.trees.expressions.functions.agg.HllUnion;
 import org.apache.doris.nereids.trees.expressions.functions.agg.HllUnionAgg;
 import org.apache.doris.nereids.trees.expressions.functions.agg.IntersectCount;
+import org.apache.doris.nereids.trees.expressions.functions.agg.MapAgg;
 import org.apache.doris.nereids.trees.expressions.functions.agg.Max;
 import org.apache.doris.nereids.trees.expressions.functions.agg.MaxBy;
 import org.apache.doris.nereids.trees.expressions.functions.agg.Min;
@@ -283,4 +284,8 @@ default R visitUnionCombinator(UnionCombinator combinator, C context) {
     default R visitJavaUdaf(JavaUdaf javaUdaf, C context) {
         return visitAggregateFunction(javaUdaf, context);
     }
+
+    default R visitMapAgg(MapAgg mapAgg, C context) {
+        return visitNullableAggregateFunction(mapAgg, context);
+    }
 }