fix(Code Node): Fix $items in Code node when using task runner (#13368)

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

@@ -850,7 +850,7 @@ describe('JsTaskRunner', () => {
 			});
 		});
 
-		test.each([['items'], ['$input.all()'], ["$('Trigger').all()"]])(
+		test.each([['items'], ['$input.all()'], ["$('Trigger').all()"], ['$items()']])(
 			'should have all input items in the context as %s',
 			async (expression) => {
 				const outcome = await executeForAllItems({

packages/@n8n/task-runner/src/js-task-runner/built-ins-parser/__tests__/built-ins-parser.test.ts

@@ -144,6 +144,23 @@ describe('BuiltInsParser', () => {
 		);
 	});
 
+	describe('$items(...)', () => {
+		it('should mark input as needed when $items() is used without arguments', () => {
+			const state = parseAndExpectOk('$items()');
+			expect(state).toEqual(new BuiltInsParserState({ needs$input: true }));
+		});
+
+		it('should require the given node when $items() is used with a static value', () => {
+			const state = parseAndExpectOk('$items("nodeName")');
+			expect(state).toEqual(new BuiltInsParserState({ neededNodeNames: new Set(['nodeName']) }));
+		});
+
+		it('should require all nodes when $items() is used with a variable', () => {
+			const state = parseAndExpectOk('var n = "name"; $items(n)');
+			expect(state).toEqual(new BuiltInsParserState({ needsAllNodes: true, needs$input: true }));
+		});
+	});
+
 	describe('$node', () => {
 		it('should require all nodes when $node is used', () => {
 			const state = parseAndExpectOk('return $node["name"];');

packages/@n8n/task-runner/src/js-task-runner/built-ins-parser/built-ins-parser.ts

@@ -54,8 +54,22 @@ export class BuiltInsParser {
 	) => {
 		// $(...)
 		const isDollar = node.callee.type === 'Identifier' && node.callee.name === '$';
-		if (!isDollar) return;
+		const isItems = node.callee.type === 'Identifier' && node.callee.name === '$items';
+		if (isDollar) {
+			this.visitDollarCallExpression(node, state, ancestors);
+		} else if (isItems) {
+			// $items(...) is a legacy syntax that is not documented but we still
+			// need to support it for backwards compatibility
+			this.visitDollarItemsCallExpression(node, state);
+		}
+	};
 
+	/** $(...) */
+	private visitDollarCallExpression(
+		node: CallExpression,
+		state: BuiltInsParserState,
+		ancestors: Node[],
+	) {
 		// $(): This is not valid, ignore
 		if (node.arguments.length === 0) {
 			return;
@@ -78,7 +92,31 @@ export class BuiltInsParser {
 
 		// Determine how $("node") is used
 		this.handlePrevNodeCall(node, state, ancestors);
-	};
+	}
+
+	/** $items(...) */
+	private visitDollarItemsCallExpression(node: CallExpression, state: BuiltInsParserState) {
+		// $items(): This gets items from the previous node
+		if (node.arguments.length === 0) {
+			state.markInputAsNeeded();
+			return;
+		}
+
+		const firstArg = node.arguments[0];
+		if (!isLiteral(firstArg)) {
+			// $items(variable): Can't easily determine statically, mark all nodes as needed
+			state.markNeedsAllNodes();
+			return;
+		}
+
+		if (typeof firstArg.value !== 'string') {
+			// $items(123): Static value, but not a string --> unsupported code --> ignore
+			return;
+		}
+
+		// $items(nodeName): Static value, mark 'nodeName' as needed
+		state.markNodeAsNeeded(firstArg.value);
+	}
 
 	private handlePrevNodeCall(_node: CallExpression, state: BuiltInsParserState, ancestors: Node[]) {
 		// $("node").item, .pairedItem or .itemMatching: In a case like this, the execution