fix(core): Improve handling of invalid objects in cleanupParameterData (no-chanhelog) (#8910)

packages/core/test/NodeExecuteFunctions.test.ts

@@ -1,4 +1,5 @@
 import {
+	cleanupParameterData,
 	copyInputItems,
 	getBinaryDataBuffer,
 	parseIncomingMessage,
@@ -7,6 +8,7 @@ import {
 	removeEmptyBody,
 	setBinaryDataBuffer,
 } from '@/NodeExecuteFunctions';
+import { DateTime } from 'luxon';
 import { mkdtempSync, readFileSync } from 'fs';
 import type { IncomingMessage } from 'http';
 import { mock } from 'jest-mock-extended';
@@ -18,6 +20,7 @@ import type {
 	IRequestOptions,
 	ITaskDataConnections,
 	IWorkflowExecuteAdditionalData,
+	NodeParameterValue,
 	Workflow,
 	WorkflowHooks,
 } from 'n8n-workflow';
@@ -414,6 +417,29 @@ describe('NodeExecuteFunctions', () => {
 		});
 	});
 
+	describe('cleanupParameterData', () => {
+		it('should stringify Luxon dates in-place', () => {
+			const input = { x: 1, y: DateTime.now() as unknown as NodeParameterValue };
+			expect(typeof input.y).toBe('object');
+			cleanupParameterData(input);
+			expect(typeof input.y).toBe('string');
+		});
+
+		it('should handle objects with nameless constructors', () => {
+			const input = { x: 1, y: { constructor: {} } as NodeParameterValue };
+			expect(typeof input.y).toBe('object');
+			cleanupParameterData(input);
+			expect(typeof input.y).toBe('object');
+		});
+
+		it('should handle objects without a constructor', () => {
+			const input = { x: 1, y: { constructor: undefined } as unknown as NodeParameterValue };
+			expect(typeof input.y).toBe('object');
+			cleanupParameterData(input);
+			expect(typeof input.y).toBe('object');
+		});
+	});
+
 	describe('copyInputItems', () => {
 		it('should pick only selected properties', () => {
 			const output = copyInputItems(