feat(watch): add --ignore flag

README.md

@@ -97,6 +97,15 @@ tsx watch ./file.ts
 All imported files are watched except from the following directories:
 `node_modules`, `bower_components`, `vendor`, `dist`, and `.*` (hidden directories).
 
+#### Ignore files from being watched
+
+If you wish to exclude files from being watched, you can pass `--ignored` multiple times:
+```sh
+tsx watch --ignored ./ignore-me.js --ignored ./ignore-me-too.js ./file.ts
+```
+
+This flag is passed to [chokidar](https://github.com/paulmillr/chokidar) thus glob patterns also work here.
+
 #### Tips
 - Press <kbd>Return</kbd> to manually rerun
 - Pass in `--clear-screen=false` to disable clearing the screen on rerun

src/watch/index.ts

@@ -27,7 +27,12 @@ const flags = {
 		description: 'Clearing the screen on rerun',
 		default: true,
 	},
-};
+	ignored: {
+		type: [String],
+		description: 'Defines files/paths to be ignored',
+		default: [],
+	},
+} as const;
 
 export const watchCommand = command({
 	name: 'watch',
@@ -47,6 +52,7 @@ export const watchCommand = command({
 		noCache: argv.flags.noCache,
 		tsconfigPath: argv.flags.tsconfig,
 		clearScreen: argv.flags.clearScreen,
+		ignored: argv.flags.ignored,
 		ipc: true,
 	};
 
@@ -123,6 +129,8 @@ export const watchCommand = command({
 
 				// Distribution files
 				'**/dist/**',
+
+				...options.ignored,
 			],
 			ignorePermissionErrors: true,
 		},

tests/specs/watch.ts

@@ -141,5 +141,70 @@ export default testSuite(async ({ describe }, fixturePath: string) => {
 			// 	await tsxProcess;
 			// }, 2000);
 		});
+
+		describe('ignore', ({ test }) => {
+			test('multiple files ignored', async () => {
+				// given
+				const initialValue = 'first round';
+				const alteredValue = 'second round';
+				const includedFilename = 'included.js';
+				const ignoredFilenames = ['ignored-1.js', 'ignored-2.js'];
+
+				const fixtures = await createFixture({
+					[includedFilename]: `
+						import { value as value1 } from './ignored-1';
+						import { value as value2 } from './ignored-2';
+						console.log(value1 + value2);
+					`.trim(),
+					[ignoredFilenames[0]]: `export const value = '${initialValue}';`,
+					[ignoredFilenames[1]]: `export const value = '${initialValue}';`,
+				});
+
+				const tsxProcess = tsx({
+					args: [
+						'watch',
+						'--clear-screen=false',
+						`--ignored=${path.join(fixtures.path, ignoredFilenames[0])}`,
+						`--ignored=${path.join(fixtures.path, ignoredFilenames[1])}`,
+						path.join(fixtures.path, includedFilename),
+					],
+				});
+
+				let aggregatedOutput = '';
+				async function onStdOut(data: Buffer) {
+					const chunkString = data.toString();
+					aggregatedOutput += chunkString;
+
+					if (new RegExp(`${initialValue}\n`).test(chunkString)) {
+						await Promise.all(ignoredFilenames.map(ignoredFilename => fixtures.writeFile(ignoredFilename, `export const value = '${alteredValue}';`)));
+						// make sure to wait for chokidar to pick up changes
+						// in the ignored file before manually triggering a rerun
+						setTimeout(async () => {
+							await fixtures.writeFile(includedFilename, 'console.log(\'TERMINATE\');');
+						}, 500);
+					} else if (chunkString.match('TERMINATE\n')) {
+						// cleanup
+						await fixtures.rm();
+						tsxProcess.kill();
+					}
+				}
+				tsxProcess.stdout?.on('data', onStdOut);
+
+				let error = false;
+				tsxProcess.stderr?.on('data', () => {
+					error = true;
+				});
+
+				// when
+				await tsxProcess;
+
+				// then
+				if (error) {
+					// manten does not come with a fail() utility.
+					expect('No error throwing').toEqual('but was thrown.');
+				}
+				expect(aggregatedOutput).not.toMatch(alteredValue);
+			});
+		});
 	});
 });