From 9bd72eaa139649811cb1114f3cf40f22d5dfe905 Mon Sep 17 00:00:00 2001
From: Michael Kret <88898367+michael-radency@users.noreply.github.com>
Date: Fri, 28 Mar 2025 17:41:26 +0200
Subject: [PATCH] fix(n8n Form Node): Hidden field fix (#14219)

---
 .../nodes-base/nodes/Form/test/utils.test.ts  | 75 ++++++++++++++++++
 packages/nodes-base/nodes/Form/utils.ts       | 77 +++++++++++--------
 2 files changed, 118 insertions(+), 34 deletions(-)

diff --git a/packages/nodes-base/nodes/Form/test/utils.test.ts b/packages/nodes-base/nodes/Form/test/utils.test.ts
index 66b584e2c7e..1dff199237a 100644
--- a/packages/nodes-base/nodes/Form/test/utils.test.ts
+++ b/packages/nodes-base/nodes/Form/test/utils.test.ts
@@ -2,7 +2,9 @@ import { mock } from 'jest-mock-extended';
 import { DateTime } from 'luxon';
 import type {
 	FormFieldsParameter,
+	IDataObject,
 	INode,
+	INodeExecutionData,
 	IWebhookFunctions,
 	MultiPartFormData,
 	NodeTypeAndVersion,
@@ -18,6 +20,7 @@ import {
 	sanitizeHtml,
 	validateResponseModeConfiguration,
 	prepareFormFields,
+	addFormResponseDataToReturnItem,
 } from '../utils';
 
 describe('FormTrigger, parseFormDescription', () => {
@@ -1032,3 +1035,75 @@ describe('validateResponseModeConfiguration', () => {
 		});
 	});
 });
+
+describe('addFormResponseDataToReturnItem', () => {
+	let returnItem: INodeExecutionData;
+
+	beforeEach(() => {
+		returnItem = { json: {} };
+	});
+
+	test('should use fieldName if fieldLabel is missing', () => {
+		const formFields: FormFieldsParameter = [
+			{ fieldName: 'Alternative Field', fieldType: 'hiddenField' },
+		] as FormFieldsParameter;
+		const bodyData: IDataObject = { 'field-0': 'Test Value' };
+
+		addFormResponseDataToReturnItem(returnItem, formFields, bodyData);
+		expect(returnItem.json['Alternative Field']).toBe('Test Value');
+	});
+
+	it('should handle null values', () => {
+		const formFields: FormFieldsParameter = [{ fieldLabel: 'Test Field', fieldType: 'text' }];
+		const bodyData: IDataObject = {};
+
+		addFormResponseDataToReturnItem(returnItem, formFields, bodyData);
+		expect(returnItem.json['Test Field']).toBeNull();
+	});
+
+	it('should process html fields and set elementName', () => {
+		const formFields: FormFieldsParameter = [
+			{ fieldLabel: 'HTML Field', elementName: 'htmlElement', fieldType: 'html' },
+		];
+		const bodyData: IDataObject = { 'field-0': '<p>HTML Content</p>' };
+
+		addFormResponseDataToReturnItem(returnItem, formFields, bodyData);
+		expect(returnItem.json.htmlElement).toBe('<p>HTML Content</p>');
+	});
+
+	it('should parse number fields correctly', () => {
+		const formFields: FormFieldsParameter = [{ fieldLabel: 'Number Field', fieldType: 'number' }];
+		const bodyData: IDataObject = { 'field-0': '42' };
+
+		addFormResponseDataToReturnItem(returnItem, formFields, bodyData);
+		expect(returnItem.json['Number Field']).toBe(42);
+	});
+
+	it('should trim text fields', () => {
+		const formFields: FormFieldsParameter = [{ fieldLabel: 'Text Field', fieldType: 'text' }];
+		const bodyData: IDataObject = { 'field-0': '   hello world   ' };
+
+		addFormResponseDataToReturnItem(returnItem, formFields, bodyData);
+		expect(returnItem.json['Text Field']).toBe('hello world');
+	});
+
+	it('should parse multiselect fields from JSON', () => {
+		const formFields: FormFieldsParameter = [
+			{ fieldLabel: 'Multi Field', fieldType: 'text', multiselect: true },
+		];
+		const bodyData: IDataObject = { 'field-0': '["option1", "option2"]' };
+
+		addFormResponseDataToReturnItem(returnItem, formFields, bodyData);
+		expect(returnItem.json['Multi Field']).toEqual(['option1', 'option2']);
+	});
+
+	it('should convert single file values to an array if multipleFiles is true', () => {
+		const formFields: FormFieldsParameter = [
+			{ fieldLabel: 'File Field', fieldType: 'file', multipleFiles: true },
+		];
+		const bodyData: IDataObject = { 'field-0': 'file1.pdf' };
+
+		addFormResponseDataToReturnItem(returnItem, formFields, bodyData);
+		expect(returnItem.json['File Field']).toEqual(['file1.pdf']);
+	});
+});
diff --git a/packages/nodes-base/nodes/Form/utils.ts b/packages/nodes-base/nodes/Form/utils.ts
index 054da42e83e..64b8cc02bea 100644
--- a/packages/nodes-base/nodes/Form/utils.ts
+++ b/packages/nodes-base/nodes/Form/utils.ts
@@ -269,6 +269,48 @@ export const validateResponseModeConfiguration = (context: IWebhookFunctions) =>
 	}
 };
 
+export function addFormResponseDataToReturnItem(
+	returnItem: INodeExecutionData,
+	formFields: FormFieldsParameter,
+	bodyData: IDataObject,
+) {
+	for (const [index, field] of formFields.entries()) {
+		const key = `field-${index}`;
+		const name = field.fieldLabel ?? field.fieldName;
+		let value = bodyData[key] ?? null;
+
+		if (value === null) {
+			returnItem.json[name] = null;
+			continue;
+		}
+
+		if (field.fieldType === 'html') {
+			if (field.elementName) {
+				returnItem.json[field.elementName] = value;
+			}
+			continue;
+		}
+
+		if (field.fieldType === 'number') {
+			value = Number(value);
+		}
+		if (field.fieldType === 'text') {
+			value = String(value).trim();
+		}
+		if (field.multiselect && typeof value === 'string') {
+			value = jsonParse(value);
+		}
+		if (field.fieldType === 'date' && value && field.formatDate !== '') {
+			value = DateTime.fromFormat(String(value), 'yyyy-mm-dd').toFormat(field.formatDate as string);
+		}
+		if (field.fieldType === 'file' && field.multipleFiles && !Array.isArray(value)) {
+			value = [value];
+		}
+
+		returnItem.json[name] = value;
+	}
+}
+
 export async function prepareFormReturnItem(
 	context: IWebhookFunctions,
 	formFields: FormFieldsParameter,
@@ -326,40 +368,7 @@ export async function prepareFormReturnItem(
 		}
 	}
 
-	for (const [index, field] of formFields.entries()) {
-		const key = `field-${index}`;
-		let value = bodyData[key] ?? null;
-
-		if (value === null) {
-			returnItem.json[field.fieldLabel] = null;
-			continue;
-		}
-
-		if (field.fieldType === 'html') {
-			if (field.elementName) {
-				returnItem.json[field.elementName] = value;
-			}
-			continue;
-		}
-
-		if (field.fieldType === 'number') {
-			value = Number(value);
-		}
-		if (field.fieldType === 'text') {
-			value = String(value).trim();
-		}
-		if (field.multiselect && typeof value === 'string') {
-			value = jsonParse(value);
-		}
-		if (field.fieldType === 'date' && value && field.formatDate !== '') {
-			value = DateTime.fromFormat(String(value), 'yyyy-mm-dd').toFormat(field.formatDate as string);
-		}
-		if (field.fieldType === 'file' && field.multipleFiles && !Array.isArray(value)) {
-			value = [value];
-		}
-
-		returnItem.json[field.fieldLabel] = value;
-	}
+	addFormResponseDataToReturnItem(returnItem, formFields, bodyData);
 
 	const timezone = useWorkflowTimezone ? context.getTimezone() : 'UTC';
 	returnItem.json.submittedAt = DateTime.now().setZone(timezone).toISO();