fix(Call n8n Sub-Workflow Tool Node): Fix json type when using $fromAI (#13102)

packages/workflow/test/FromAIParseUtils.test.ts

@@ -1,7 +1,8 @@
 import {
 	extractFromAICalls,
-	type FromAIArgument,
 	traverseNodeParameters,
+	type FromAIArgument,
+	generateZodSchema,
 } from '@/FromAIParseUtils';
 
 // Note that for historic reasons a lot of testing of this file happens indirectly in `packages/core/test/CreateNodeAsTool.test.ts`
@@ -85,3 +86,61 @@ describe('traverseNodeParameters', () => {
 		},
 	);
 });
+
+describe('JSON Type Parsing via generateZodSchema', () => {
+	it('should correctly parse a JSON parameter without default', () => {
+		// Use an actual $fromAI call string via extractFromAICalls:
+		const [arg] = extractFromAICalls(
+			'$fromAI("jsonWithoutDefault", "JSON parameter without default", "json")',
+		);
+		const schema = generateZodSchema(arg);
+
+		// Valid non-empty JSON objects should pass.
+		expect(() => schema.parse({ key: 'value' })).not.toThrow();
+		expect(schema.parse({ key: 'value' })).toEqual({ key: 'value' });
+
+		// Parsing an empty object should throw a validation error.
+		expect(() => schema.parse({})).toThrowError(
+			/Value must be a non-empty object or a non-empty array/,
+		);
+	});
+
+	it('should correctly parse a JSON parameter with a valid default', () => {
+		const [arg] = extractFromAICalls(
+			'$fromAI("jsonWithValidDefault", "JSON parameter with valid default", "json", "{"key": "defaultValue"}")',
+		);
+		const schema = generateZodSchema(arg);
+
+		// The default value is now stored as a parsed object.
+		expect(schema._def.defaultValue()).toEqual({ key: 'defaultValue' });
+	});
+
+	it('should parse a JSON parameter with an empty default', () => {
+		const [arg] = extractFromAICalls(
+			'$fromAI("jsonEmptyDefault", "JSON parameter with empty default", "json", "{}")',
+		);
+		const schema = generateZodSchema(arg);
+
+		// The default value is stored as an empty object.
+		expect(schema._def.defaultValue()).toEqual({});
+
+		// Parsing an empty object should throw a validation error.
+		expect(() => schema.parse({})).toThrowError(
+			/Value must be a non-empty object or a non-empty array/,
+		);
+	});
+
+	it('should use provided JSON value over the default value', () => {
+		const [arg] = extractFromAICalls(
+			'$fromAI("jsonParamCustom", "JSON parameter with custom default", "json", "{"initial": "value"}")',
+		);
+		const schema = generateZodSchema(arg);
+
+		// Check that the stored default value parses to the expected object.
+		expect(schema._def.defaultValue()).toEqual({ initial: 'value' });
+
+		// When a new valid value is provided, the schema should use it.
+		const newValue = { newKey: 'newValue' };
+		expect(schema.parse(newValue)).toEqual(newValue);
+	});
+});