Apply fix from Carlos

Author: svilen-mihaylov-elastic

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/EsqlFunctionRegistry.java

@@ -12,6 +12,7 @@
 import org.elasticsearch.common.util.FeatureFlag;
 import org.elasticsearch.xpack.esql.core.QlIllegalArgumentException;
 import org.elasticsearch.xpack.esql.core.expression.Expression;
+import org.elasticsearch.xpack.esql.core.expression.MapExpression;
 import org.elasticsearch.xpack.esql.core.expression.function.Function;
 import org.elasticsearch.xpack.esql.core.tree.Source;
 import org.elasticsearch.xpack.esql.core.type.DataType;
@@ -1025,7 +1026,12 @@ protected static <T extends Function> FunctionDefinition def(
             } else if (hasMinimumOne == false && children.size() < 2) {
                 throw new QlIllegalArgumentException("expects at least two arguments");
             }
-            return ctorRef.build(source, children.get(0), children.subList(1, children.size() - 1), children.getLast());
+            Expression options = children.getLast();
+            if (options instanceof MapExpression) {
+                return ctorRef.build(source, children.get(0), children.subList(1, children.size() - 1), options);
+            }
+
+            return ctorRef.build(source, children.get(0), children.subList(1, children.size()), null);
         };
         return def(function, builder, names);
     }

x-pack/plugin/esql/src/main/java/org/elasticsearch/xpack/esql/expression/function/fulltext/MultiMatch.java

@@ -307,13 +307,18 @@ public String getWriteableName() {
 
     @Override
     public Expression replaceChildren(List<Expression> newChildren) {
-        return new MultiMatch(
-            source(),
-            newChildren.getFirst(),
-            newChildren.subList(1, newChildren.size() - 1),
-            newChildren.getLast(),
-            queryBuilder()
-        );
+        if (newChildren.getLast() instanceof MapExpression) {
+            // if the last child is a MapExpression, it is the options map
+            return new MultiMatch(
+                source(),
+                newChildren.getFirst(),
+                newChildren.subList(1, newChildren.size() - 1),
+                newChildren.getLast(),
+                queryBuilder()
+            );
+        }
+
+        return new MultiMatch(source(), newChildren.getFirst(), newChildren.subList(1, newChildren.size()), null, queryBuilder());
     }
 
     @Override

x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/analysis/VerifierTests.java

@@ -2325,6 +2325,8 @@ public void testQueryStringOptions() {
 
     public void testMultiMatchOptions() {
         // Check positive cases
+        query("FROM test | WHERE MULTI_MATCH(\"Jean\", first_name)");
+        query("FROM test | WHERE MULTI_MATCH(\"Jean\", first_name, {\"analyzer\": \"standard\"})");
         query("FROM test | WHERE MULTI_MATCH(\"Jean\", first_name, last_name, {\"analyzer\": \"standard\"})");
         query("FROM test | WHERE MULTI_MATCH(\"Jean\", \"first_name\", last_name, {\"slop\": 10})");
         query("FROM test | WHERE MULTI_MATCH(\"Jean\", first_name, last_name, {\"auto_generate_synonyms_phrase_query\": true})");