fix(core): Allow index as top-level item key for Code node (#12469)

packages/@n8n/task-runner/src/js-task-runner/__tests__/result-validation.test.ts

@@ -28,6 +28,7 @@ describe('result validation', () => {
 			['binary', {}],
 			['pairedItem', {}],
 			['error', {}],
+			['index', {}], // temporarily allowed until refactored out
 		])(
 			'should not throw an error if the output item has %s key in addition to json',
 			(key, value) => {

packages/@n8n/task-runner/src/js-task-runner/result-validation.ts

@@ -4,7 +4,19 @@ import type { INodeExecutionData } from 'n8n-workflow';
 import { ValidationError } from './errors/validation-error';
 import { isObject } from './obj-utils';
 
-export const REQUIRED_N8N_ITEM_KEYS = new Set(['json', 'binary', 'pairedItem', 'error']);
+export const REQUIRED_N8N_ITEM_KEYS = new Set([
+	'json',
+	'binary',
+	'pairedItem',
+	'error',
+
+	/**
+	 * The `index` key was added accidentally to Function, FunctionItem, Gong,
+	 * Execute Workflow, and ToolWorkflowV2, so we need to allow it temporarily.
+	 * Once we stop using it in all nodes, we can stop allowing the `index` key.
+	 */
+	'index',
+]);
 
 function validateTopLevelKeys(item: INodeExecutionData, itemIndex: number) {
 	for (const key in item) {