Initial commit: twitter-cli for posting tweets via GraphQL API

Features:
- Post tweets and replies via Twitter GraphQL API
- Cookie extraction from Chrome (macOS)
- Env var and CLI argument authentication
- 19 passing tests with vitest
- Biome for linting

tests/twitter-client.test.ts

@@ -0,0 +1,162 @@
+import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest';
+import { TwitterClient } from '../src/lib/twitter-client.js';
+
+describe('TwitterClient', () => {
+	const validCookies = {
+		authToken: 'test_auth_token',
+		ct0: 'test_ct0_token',
+		source: 'test',
+	};
+
+	describe('constructor', () => {
+		it('should throw if authToken is missing', () => {
+			expect(
+				() =>
+					new TwitterClient({
+						cookies: { authToken: null, ct0: 'test', source: null },
+					}),
+			).toThrow('Both authToken and ct0 cookies are required');
+		});
+
+		it('should throw if ct0 is missing', () => {
+			expect(
+				() =>
+					new TwitterClient({
+						cookies: { authToken: 'test', ct0: null, source: null },
+					}),
+			).toThrow('Both authToken and ct0 cookies are required');
+		});
+
+		it('should create client with valid cookies', () => {
+			const client = new TwitterClient({ cookies: validCookies });
+			expect(client).toBeInstanceOf(TwitterClient);
+		});
+	});
+
+	describe('tweet', () => {
+		let mockFetch: ReturnType<typeof vi.fn>;
+
+		beforeEach(() => {
+			mockFetch = vi.fn();
+			global.fetch = mockFetch;
+		});
+
+		afterEach(() => {
+			vi.restoreAllMocks();
+		});
+
+		it('should post a tweet successfully', async () => {
+			mockFetch.mockResolvedValueOnce({
+				ok: true,
+				json: async () => ({
+					data: {
+						create_tweet: {
+							tweet_results: {
+								result: {
+									rest_id: '1234567890',
+									legacy: {
+										full_text: 'Hello world!',
+									},
+								},
+							},
+						},
+					},
+				}),
+			});
+
+			const client = new TwitterClient({ cookies: validCookies });
+			const result = await client.tweet('Hello world!');
+
+			expect(result.success).toBe(true);
+			expect(result.tweetId).toBe('1234567890');
+			expect(mockFetch).toHaveBeenCalledTimes(1);
+
+			const [url, options] = mockFetch.mock.calls[0];
+			expect(url).toContain('CreateTweet');
+			expect(options.method).toBe('POST');
+
+			const body = JSON.parse(options.body);
+			expect(body.variables.tweet_text).toBe('Hello world!');
+		});
+
+		it('should handle API errors', async () => {
+			mockFetch.mockResolvedValueOnce({
+				ok: true,
+				json: async () => ({
+					errors: [{ message: 'Rate limit exceeded', code: 88 }],
+				}),
+			});
+
+			const client = new TwitterClient({ cookies: validCookies });
+			const result = await client.tweet('Test');
+
+			expect(result.success).toBe(false);
+			expect(result.error).toContain('Rate limit exceeded');
+		});
+
+		it('should handle HTTP errors', async () => {
+			mockFetch.mockResolvedValueOnce({
+				ok: false,
+				status: 403,
+				text: async () => 'Forbidden',
+			});
+
+			const client = new TwitterClient({ cookies: validCookies });
+			const result = await client.tweet('Test');
+
+			expect(result.success).toBe(false);
+			expect(result.error).toContain('HTTP 403');
+		});
+
+		it('should handle network errors', async () => {
+			mockFetch.mockRejectedValueOnce(new Error('Network error'));
+
+			const client = new TwitterClient({ cookies: validCookies });
+			const result = await client.tweet('Test');
+
+			expect(result.success).toBe(false);
+			expect(result.error).toBe('Network error');
+		});
+	});
+
+	describe('reply', () => {
+		let mockFetch: ReturnType<typeof vi.fn>;
+
+		beforeEach(() => {
+			mockFetch = vi.fn();
+			global.fetch = mockFetch;
+		});
+
+		afterEach(() => {
+			vi.restoreAllMocks();
+		});
+
+		it('should post a reply with correct reply_to_tweet_id', async () => {
+			mockFetch.mockResolvedValueOnce({
+				ok: true,
+				json: async () => ({
+					data: {
+						create_tweet: {
+							tweet_results: {
+								result: {
+									rest_id: '9876543210',
+								},
+							},
+						},
+					},
+				}),
+			});
+
+			const client = new TwitterClient({ cookies: validCookies });
+			const result = await client.reply('This is a reply', '1234567890');
+
+			expect(result.success).toBe(true);
+			expect(result.tweetId).toBe('9876543210');
+
+			const [, options] = mockFetch.mock.calls[0];
+			const body = JSON.parse(options.body);
+			expect(body.variables.reply.in_reply_to_tweet_id).toBe('1234567890');
+			expect(body.variables.tweet_text).toBe('This is a reply');
+		});
+	});
+});