test_runner: print info when test restarts

Xstoudi · aduh95 · commit 6e1beda333ac · 2026-01-20T14:36:01.000+01:00
When using spec reporter and running test in watch mode, print an info message containing the current datetime when tests restart. Fixes: #57206 PR-URL: #61160 Reviewed-By: Colin Ihrig <cjihrig@gmail.com> Reviewed-By: Moshe Atlow <moshe@atlow.co.il>
diff --git a/lib/internal/test_runner/reporter/spec.js b/lib/internal/test_runner/reporter/spec.js
@@ -5,6 +5,8 @@ const {
   ArrayPrototypePush,
   ArrayPrototypeShift,
   ArrayPrototypeUnshift,
+  Date,
+  DatePrototypeToLocaleString,
 } = primordials;
 const assert = require('assert');
 const Transform = require('internal/streams/transform');
@@ -101,6 +103,9 @@ class SpecReporter extends Transform {
         if (data.file === undefined) {
           return this.#formatFailedTestResults();
         }
+        break;
+      case 'test:watch:restarted':
+        return `\nRestarted at ${DatePrototypeToLocaleString(new Date())}\n`;
     }
   }
   _transform({ type, data }, encoding, callback) {
diff --git a/test/test-runner/test-output-spec-reporter-watch-restart.mjs b/test/test-runner/test-output-spec-reporter-watch-restart.mjs
@@ -0,0 +1,18 @@
+import '../common/index.mjs';
+import { spec as SpecReporter } from 'node:test/reporters';
+import assert from 'node:assert';
+
+const reporter = new SpecReporter();
+let output = '';
+
+reporter.on('data', (chunk) => {
+  output += chunk;
+});
+
+reporter.write({
+  type: 'test:watch:restarted',
+});
+
+reporter.end();
+
+assert.match(output, /Restarted at .+/);

Original file line number	Diff line number	Diff line change
`@@ -5,6 +5,8 @@ const {`
`5`	`5`	`ArrayPrototypePush,`
`6`	`6`	`ArrayPrototypeShift,`
`7`	`7`	`ArrayPrototypeUnshift,`
	`8`	`+ Date,`
	`9`	`+ DatePrototypeToLocaleString,`
`8`	`10`	`} = primordials;`
`9`	`11`	`const assert = require('assert');`
`10`	`12`	`const Transform = require('internal/streams/transform');`
`@@ -101,6 +103,9 @@ class SpecReporter extends Transform {`
`101`	`103`	`if (data.file === undefined) {`
`102`	`104`	`return this.#formatFailedTestResults();`
`103`	`105`	`}`
	`106`	`+ break;`
	`107`	`+ case 'test:watch:restarted':`
	`108`	+ return `\nRestarted at ${DatePrototypeToLocaleString(new Date())}\n`;
`104`	`109`	`}`
`105`	`110`	`}`
`106`	`111`	`_transform({ type, data }, encoding, callback) {`