Added intermediateStateDesc to suppliers

Author: ivancea

x-pack/plugin/esql/compute/gen/src/main/java/org/elasticsearch/compute/gen/AggregatorFunctionSupplierImplementer.java

@@ -31,6 +31,7 @@
 
 import static org.elasticsearch.compute.gen.Types.AGGREGATOR_FUNCTION_SUPPLIER;
 import static org.elasticsearch.compute.gen.Types.DRIVER_CONTEXT;
+import static org.elasticsearch.compute.gen.Types.LIST_AGG_FUNC_DESC;
 import static org.elasticsearch.compute.gen.Types.LIST_INTEGER;
 import static org.elasticsearch.compute.gen.Types.STRING;
 import static org.elasticsearch.compute.gen.Types.WARNINGS;
@@ -99,11 +100,9 @@ private TypeSpec type() {
         }
         createParameters.stream().forEach(p -> p.declareField(builder));
         builder.addMethod(ctor());
-        if (aggregatorImplementer != null) {
-            builder.addMethod(aggregator());
-        } else {
-            builder.addMethod(unsupportedNonGroupingAggregator());
-        }
+        builder.addMethod(nonGroupingIntermediateStateDesc());
+        builder.addMethod(groupingIntermediateStateDesc());
+        builder.addMethod(aggregator());
         builder.addMethod(groupingAggregator());
         builder.addMethod(describe());
         return builder.build();
@@ -123,19 +122,48 @@ private MethodSpec ctor() {
         return builder.build();
     }
 
-    private MethodSpec unsupportedNonGroupingAggregator() {
-        MethodSpec.Builder builder = MethodSpec.methodBuilder("aggregator")
-            .addParameter(DRIVER_CONTEXT, "driverContext")
-            .returns(Types.AGGREGATOR_FUNCTION);
+    private MethodSpec nonGroupingIntermediateStateDesc() {
+        MethodSpec.Builder builder = MethodSpec.methodBuilder("nonGroupingIntermediateStateDesc");
+        builder.addAnnotation(Override.class).addModifiers(Modifier.PUBLIC);
+        builder.returns(LIST_AGG_FUNC_DESC);
+
+        if (aggregatorImplementer == null) {
+            builder.addStatement("throw new UnsupportedOperationException($S)", "non-grouping aggregator is not supported");
+            return builder.build();
+        }
+
+        builder.addStatement(
+            "return $T.intermediateStateDesc()",
+            aggregatorImplementer.implementation()
+        );
+
+        return builder.build();
+    }
+
+    private MethodSpec groupingIntermediateStateDesc() {
+        MethodSpec.Builder builder = MethodSpec.methodBuilder("groupingIntermediateStateDesc");
         builder.addAnnotation(Override.class).addModifiers(Modifier.PUBLIC);
-        builder.addStatement("throw new UnsupportedOperationException($S)", "non-grouping aggregator is not supported");
+        builder.returns(LIST_AGG_FUNC_DESC);
+
+        builder.addStatement(
+            "return $T.intermediateStateDesc()",
+            groupingAggregatorImplementer.implementation()
+        );
+
         return builder.build();
     }
 
     private MethodSpec aggregator() {
         MethodSpec.Builder builder = MethodSpec.methodBuilder("aggregator");
         builder.addAnnotation(Override.class).addModifiers(Modifier.PUBLIC);
         builder.addParameter(DRIVER_CONTEXT, "driverContext");
+
+        if (aggregatorImplementer == null) {
+            builder.returns(Types.AGGREGATOR_FUNCTION);
+            builder.addStatement("throw new UnsupportedOperationException($S)", "non-grouping aggregator is not supported");
+            return builder.build();
+        }
+
         builder.returns(aggregatorImplementer.implementation());
 
         if (hasWarnings) {
@@ -155,6 +183,7 @@ private MethodSpec aggregator() {
             ).collect(Collectors.joining(", "))
         );
 
+
         return builder.build();
     }