feat(watch): --include CLI flag to watch additional files

src/watch/index.ts

@@ -36,6 +36,10 @@ const flags = {
 		type: [String],
 		description: 'Paths & globs to exclude from being watched',
 	},
+	include: {
+		type: [String],
+		description: 'Paths & globs to include in watch',
+	},
 } as const;
 
 export const watchCommand = command({
@@ -60,6 +64,7 @@ export const watchCommand = command({
 		tsconfigPath: argv.flags.tsconfig,
 		clearScreen: argv.flags.clearScreen,
 		ignore: argv.flags.ignore,
+		include: argv.flags.include,
 		ipc: true,
 	};
 
@@ -195,7 +200,7 @@ export const watchCommand = command({
 	 * As an alternative, we watch cwd and all run-time dependencies
 	 */
 	const watcher = watch(
-		argv._,
+		[...argv._, ...options.include],
 		{
 			cwd: process.cwd(),
 			ignoreInitial: true,

tests/specs/watch.ts

@@ -7,6 +7,9 @@ import type { NodeApis } from '../utils/tsx.js';
 import { processInteract } from '../utils/process-interact.js';
 import { createPackageJson } from '../fixtures.js';
 
+// reRun debounce from src/watch/index.ts
+const watchDebounce = 100;
+
 export default testSuite(async ({ describe }, { tsx }: NodeApis) => {
 	describe('watch', async ({ test, describe, onFinish }) => {
 		const fixture = await createFixture({
@@ -300,5 +303,57 @@ export default testSuite(async ({ describe }, { tsx }: NodeApis) => {
 				expect(p.stderr).toBe('');
 			}, 10_000);
 		});
+
+		describe('include', ({ test }) => {
+			test('file path & glob', async () => {
+				const entryFile = 'index.js';
+				const fileA = 'file-a';
+				const fileB = 'directory/file-b';
+				await using fixture = await createFixture({
+					[entryFile]: `
+						import fs from 'fs/promises';
+						Promise.all([
+							fs.readFile('./${fileA}', 'utf8'),
+							fs.readFile('./${fileB}', 'utf8')
+						]).then(([a, b]) => {
+							console.log(a + ' ' + b);
+						}).catch(console.error);
+					`.trim(),
+					[fileA]: 'content-a',
+					[fileB]: 'content-b',
+				});
+
+				const tsxProcess = tsx(
+					[
+						'watch',
+						'--clear-screen=false',
+						`--include=${fileA}`,
+						`--include=${path.join(fixture.path, 'directory/*')}`,
+						entryFile,
+					],
+					fixture.path,
+				);
+
+				tsxProcess.stdout?.on('data', async (data: Buffer) => {
+					const chunkString = data.toString();
+					if (chunkString.includes('content-a content-b')) {
+						await fixture.writeFile(fileA, 'update-a');
+						await setTimeout(watchDebounce + 10);
+						await fixture.writeFile(fileB, 'update-b');
+					} else if (chunkString.includes('update-a update-b')) {
+						await fixture.writeFile(entryFile, 'console.log("TERMINATE")');
+					} else if (chunkString.includes('TERMINATE')) {
+						tsxProcess.kill();
+					}
+				});
+
+				const tsxProcessResolved = await tsxProcess;
+				const stdout = stripAnsi(tsxProcessResolved.stdout);
+				expect(stdout).toContain(`change in ./${fileA}`);
+				expect(stdout).toContain(`change in ./${fileB}`);
+				expect(stdout).toContain(`change in ./${entryFile}`);
+				expect(tsxProcessResolved.stderr).toBe('');
+			}, 10_000);
+		});
 	});
 });