fix(RSS Feed Trigger Node): Handle empty items gracefully (#10855)

packages/nodes-base/nodes/RssFeedRead/test/RssFeedRead.test.ts

@@ -0,0 +1,64 @@
+import { mock } from 'jest-mock-extended';
+import type { IPollFunctions } from 'n8n-workflow';
+import Parser from 'rss-parser';
+import { returnJsonArray } from 'n8n-core';
+import { RssFeedReadTrigger } from '../RssFeedReadTrigger.node';
+
+jest.mock('rss-parser');
+
+const now = new Date('2024-02-01T01:23:45.678Z');
+jest.useFakeTimers({ now });
+
+describe('RssFeedReadTrigger', () => {
+	describe('poll', () => {
+		const feedUrl = 'https://example.com/feed';
+		const lastItemDate = '2022-01-01T00:00:00.000Z';
+		const newItemDate = '2022-01-02T00:00:00.000Z';
+
+		const node = new RssFeedReadTrigger();
+		const pollFunctions = mock<IPollFunctions>({
+			helpers: mock({ returnJsonArray }),
+		});
+
+		it('should throw an error if the feed URL is empty', async () => {
+			pollFunctions.getNodeParameter.mockReturnValue('');
+
+			await expect(node.poll.call(pollFunctions)).rejects.toThrowError();
+
+			expect(pollFunctions.getNodeParameter).toHaveBeenCalledWith('feedUrl');
+			expect(Parser.prototype.parseURL).not.toHaveBeenCalled();
+		});
+
+		it('should return new items from the feed', async () => {
+			const pollData = mock({ lastItemDate });
+			pollFunctions.getNodeParameter.mockReturnValue(feedUrl);
+			pollFunctions.getWorkflowStaticData.mockReturnValue(pollData);
+			(Parser.prototype.parseURL as jest.Mock).mockResolvedValue({
+				items: [{ isoDate: lastItemDate }, { isoDate: newItemDate }],
+			});
+
+			const result = await node.poll.call(pollFunctions);
+
+			expect(result).toEqual([[{ json: { isoDate: newItemDate } }]]);
+			expect(pollFunctions.getWorkflowStaticData).toHaveBeenCalledWith('node');
+			expect(pollFunctions.getNodeParameter).toHaveBeenCalledWith('feedUrl');
+			expect(Parser.prototype.parseURL).toHaveBeenCalledWith(feedUrl);
+			expect(pollData.lastItemDate).toEqual(newItemDate);
+		});
+
+		it('should return null if the feed is empty', async () => {
+			const pollData = mock({ lastItemDate });
+			pollFunctions.getNodeParameter.mockReturnValue(feedUrl);
+			pollFunctions.getWorkflowStaticData.mockReturnValue(pollData);
+			(Parser.prototype.parseURL as jest.Mock).mockResolvedValue({ items: [] });
+
+			const result = await node.poll.call(pollFunctions);
+
+			expect(result).toEqual(null);
+			expect(pollFunctions.getWorkflowStaticData).toHaveBeenCalledWith('node');
+			expect(pollFunctions.getNodeParameter).toHaveBeenCalledWith('feedUrl');
+			expect(Parser.prototype.parseURL).toHaveBeenCalledWith(feedUrl);
+			expect(pollData.lastItemDate).toEqual(lastItemDate);
+		});
+	});
+});