watch: fix missing file error when --watch used without argument

Signed-off-by: anshikakalpana <anshikajain196872@gmail.com>

Author: Anshikakalpana

lib/internal/main/watch_mode.js

@@ -31,6 +31,11 @@ const { once } = require('events');
 prepareMainThreadExecution(false, false);
 markBootstrapComplete();
 
+if (!process.argv[1]) {
+  process.stderr.write('node: --watch requires specifying a file\n');
+  process.exit(9);
+}
+
 const kKillSignal = convertToValidSignal(getOptionValue('--watch-kill-signal'));
 const kShouldFilterModules = getOptionValue('--watch-path').length === 0;
 const kEnvFiles = getOptionValue('--env-file');

test/parallel/test-watch-mode-requires-file.mjs

@@ -0,0 +1,7 @@
+import '../common/index.mjs';
+import { spawnSync } from 'node:child_process';
+import assert from 'node:assert';
+
+const result = spawnSync(process.execPath, ['--watch'], { encoding: 'utf8' });
+assert.strictEqual(result.status, 9);
+assert.match(result.stderr, /--watch requires specifying a file/);