From f5f67ae4a76f15df47fdf3f1253aba695c3d0ab9 Mon Sep 17 00:00:00 2001
From: cjihrig <cjihrig@gmail.com>
Date: Thu, 5 Sep 2024 17:42:37 -0400
Subject: [PATCH] test_runner: detect only tests when isolation is off

This commit updates the way the test runner processes 'only'
tests when process-based test isolation is disabled. The
--test-only flag is no longer necessary in this scenario. The
test runner will automatically detect 'only' tests and apply the
appropriate filtering.

PR-URL: https://github.com/nodejs/node/pull/54832
Reviewed-By: Chemi Atlow <chemi@atlow.co.il>
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Moshe Atlow <moshe@atlow.co.il>
---
 doc/api/cli.md                                      | 2 +-
 doc/api/test.md                                     | 8 ++++----
 lib/internal/test_runner/harness.js                 | 3 ++-
 test/parallel/test-runner-no-isolation-filtering.js | 4 +---
 test/parallel/test-runner-no-isolation-hooks.mjs    | 9 ---------
 5 files changed, 8 insertions(+), 18 deletions(-)

diff --git a/doc/api/cli.md b/doc/api/cli.md
index 01efb97e31be23..4028e0d374b179 100644
--- a/doc/api/cli.md
+++ b/doc/api/cli.md
@@ -2336,7 +2336,7 @@ changes:
 -->
 
 Configures the test runner to only execute top level tests that have the `only`
-option set.
+option set. This flag is not necessary when test isolation is disabled.
 
 ### `--test-reporter`
 
diff --git a/doc/api/test.md b/doc/api/test.md
index 19819202d1d2e1..82cba9842aad34 100644
--- a/doc/api/test.md
+++ b/doc/api/test.md
@@ -229,10 +229,10 @@ const { describe, it } = require('node:test');
 
 ## `only` tests
 
-If Node.js is started with the [`--test-only`][] command-line option, it is
-possible to skip all tests except for a selected subset by passing
-the `only` option to the tests that should run. When a test with the `only`
-option is set, all subtests are also run.
+If Node.js is started with the [`--test-only`][] command-line option, or test
+isolation is disabled, it is possible to skip all tests except for a selected
+subset by passing the `only` option to the tests that should run. When a test
+with the `only` option is set, all subtests are also run.
 If a suite has the `only` option set, all tests within the suite are run,
 unless it has descendants with the `only` option set, in which case only those
 tests are run.
diff --git a/lib/internal/test_runner/harness.js b/lib/internal/test_runner/harness.js
index f91cc4f8592aec..50ecb290bfa65a 100644
--- a/lib/internal/test_runner/harness.js
+++ b/lib/internal/test_runner/harness.js
@@ -38,7 +38,8 @@ function createTestTree(rootTestOptions, globalOptions) {
   const buildPhaseDeferred = createDeferredPromise();
   const isFilteringByName = globalOptions.testNamePatterns ||
                             globalOptions.testSkipPatterns;
-  const isFilteringByOnly = globalOptions.only;
+  const isFilteringByOnly = globalOptions.only || (globalOptions.isTestRunner &&
+                                                   globalOptions.isolation === 'none');
   const harness = {
     __proto__: null,
     buildPromise: buildPhaseDeferred.promise,
diff --git a/test/parallel/test-runner-no-isolation-filtering.js b/test/parallel/test-runner-no-isolation-filtering.js
index 21db267d5323c6..b99b4783ddcc1c 100644
--- a/test/parallel/test-runner-no-isolation-filtering.js
+++ b/test/parallel/test-runner-no-isolation-filtering.js
@@ -45,10 +45,8 @@ test('works with --test-name-pattern', () => {
 
   assert.strictEqual(child.status, 0);
   assert.strictEqual(child.signal, null);
-  assert.match(stdout, /# tests 1/);
+  assert.match(stdout, /# tests 0/);
   assert.match(stdout, /# suites 0/);
-  assert.match(stdout, /# pass 1/);
-  assert.match(stdout, /ok 1 - test one/);
 });
 
 test('works with --test-skip-pattern', () => {
diff --git a/test/parallel/test-runner-no-isolation-hooks.mjs b/test/parallel/test-runner-no-isolation-hooks.mjs
index 2c1570d2d75514..ce7b1388e92425 100644
--- a/test/parallel/test-runner-no-isolation-hooks.mjs
+++ b/test/parallel/test-runner-no-isolation-hooks.mjs
@@ -30,15 +30,6 @@ const order = [
   'afterEach one: suite one - test',
   'afterEach two: suite one - test',
 
-  'beforeEach(): global',
-  'beforeEach one: test one',
-  'beforeEach two: test one',
-  'test one',
-
-  'afterEach(): global',
-  'afterEach one: test one',
-  'afterEach two: test one',
-
   'before suite two: suite two',
   'beforeEach(): global',
   'beforeEach one: suite two - test',