nodejs · MoLow · Jul 5, 2026
diff --git a/doc/api/test.md b/doc/api/test.md
@@ -3440,6 +3440,10 @@ added:
   - v18.9.0
   - v16.19.0
 changes:
+  - version: REPLACEME
+    pr-url: https://github.com/nodejs/node/pull/64309
+    description: Added `entryFile` to events forwarded from child processes
+                 when tests run with process isolation.
   - version: v26.3.0
     pr-url: https://github.com/nodejs/node/pull/63435
     description: Added `parentId` to test events that carry a `testId`.
@@ -3524,6 +3528,10 @@ Emitted when code coverage is enabled and all tests have completed.
       * `cause` {Error} The actual error thrown by the test.
     * `type` {string|undefined} The type of the test, used to denote whether
       this is a suite.
+  * `entryFile` {string|undefined} The path of the test file that was
+    executed as the entry point of the child process that emitted this event.
+    Only present when tests run with process isolation. May differ from
+    `file` when the test is defined in a module imported by the entry file.
   * `file` {string|undefined} The path of the test file,
     `undefined` if test was run through the REPL.
   * `line` {number|undefined} The line number where the test is defined, or
@@ -3553,6 +3561,10 @@ The corresponding declaration ordered events are `'test:pass'` and `'test:fail'`
 * `data` {Object}
   * `column` {number|undefined} The column number where the test is defined, or
     `undefined` if the test was run through the REPL.
+  * `entryFile` {string|undefined} The path of the test file that was
+    executed as the entry point of the child process that emitted this event.
+    Only present when tests run with process isolation. May differ from
+    `file` when the test is defined in a module imported by the entry file.
   * `file` {string|undefined} The path of the test file,
     `undefined` if test was run through the REPL.
   * `line` {number|undefined} The line number where the test is defined, or
@@ -3579,6 +3591,10 @@ defined. The corresponding declaration ordered event is `'test:start'`.
 * `data` {Object}
   * `column` {number|undefined} The column number where the test is defined, or
     `undefined` if the test was run through the REPL.
+  * `entryFile` {string|undefined} The path of the test file that was
+    executed as the entry point of the child process that emitted this event.
+    Only present when tests run with process isolation. May differ from
+    `file` when the test is defined in a module imported by the entry file.
   * `file` {string|undefined} The path of the test file,
     `undefined` if test was run through the REPL.
   * `line` {number|undefined} The line number where the test is defined, or
@@ -3600,6 +3616,10 @@ defined.
 * `data` {Object}
   * `column` {number|undefined} The column number where the test is defined, or
     `undefined` if the test was run through the REPL.
+  * `entryFile` {string|undefined} The path of the test file that was
+    executed as the entry point of the child process that emitted this event.
+    Only present when tests run with process isolation. May differ from
+    `file` when the test is defined in a module imported by the entry file.
   * `file` {string|undefined} The path of the test file,
     `undefined` if test was run through the REPL.
   * `line` {number|undefined} The line number where the test is defined, or
@@ -3632,6 +3652,10 @@ Emitted when a test is enqueued for execution.
       this is a suite.
     * `attempt` {number|undefined} The attempt number of the test run,
       present only when using the [`--test-rerun-failures`][] flag.
+  * `entryFile` {string|undefined} The path of the test file that was
+    executed as the entry point of the child process that emitted this event.
+    Only present when tests run with process isolation. May differ from
+    `file` when the test is defined in a module imported by the entry file.
   * `file` {string|undefined} The path of the test file,
     `undefined` if test was run through the REPL.
   * `line` {number|undefined} The line number where the test is defined, or
@@ -3697,6 +3721,10 @@ since the parent runner only knows about file-level tests. When using
       present only when using the [`--test-rerun-failures`][] flag.
     * `passed_on_attempt` {number|undefined} The attempt number the test passed on,
       present only when using the [`--test-rerun-failures`][] flag.
+  * `entryFile` {string|undefined} The path of the test file that was
+    executed as the entry point of the child process that emitted this event.
+    Only present when tests run with process isolation. May differ from
+    `file` when the test is defined in a module imported by the entry file.
   * `file` {string|undefined} The path of the test file,
     `undefined` if test was run through the REPL.
   * `line` {number|undefined} The line number where the test is defined, or
@@ -3726,6 +3754,10 @@ The corresponding execution ordered event is `'test:complete'`.
 * `data` {Object}
   * `column` {number|undefined} The column number where the test is defined, or
     `undefined` if the test was run through the REPL.
+  * `entryFile` {string|undefined} The path of the test file that was
+    executed as the entry point of the child process that emitted this event.
+    Only present when tests run with process isolation. May differ from
+    `file` when the test is defined in a module imported by the entry file.
   * `file` {string|undefined} The path of the test file,
     `undefined` if test was run through the REPL.
   * `line` {number|undefined} The line number where the test is defined, or
@@ -3742,6 +3774,10 @@ defined.
 * `data` {Object}
   * `column` {number|undefined} The column number where the test is defined, or
     `undefined` if the test was run through the REPL.
+  * `entryFile` {string|undefined} The path of the test file that was
+    executed as the entry point of the child process that emitted this event.
+    Only present when tests run with process isolation. May differ from
+    `file` when the test is defined in a module imported by the entry file.
   * `file` {string|undefined} The path of the test file,
     `undefined` if test was run through the REPL.
   * `line` {number|undefined} The line number where the test is defined, or
@@ -3766,6 +3802,9 @@ The corresponding execution ordered event is `'test:dequeue'`.
 ### Event: `'test:stderr'`
 
 * `data` {Object}
+  * `entryFile` {string|undefined} The path of the test file that was
+    executed as the entry point of the child process that emitted this event.
+    Only present when tests run with process isolation.
   * `file` {string} The path of the test file.
   * `message` {string} The message written to `stderr`.
 
@@ -3777,6 +3816,9 @@ defined.
 ### Event: `'test:stdout'`
 
 * `data` {Object}
+  * `entryFile` {string|undefined} The path of the test file that was
+    executed as the entry point of the child process that emitted this event.
+    Only present when tests run with process isolation.
   * `file` {string} The path of the test file.
   * `message` {string} The message written to `stdout`.
 

diff --git a/lib/internal/test_runner/runner.js b/lib/internal/test_runner/runner.js
@@ -295,6 +295,10 @@ class FileTest extends Test {
           ArrayPrototypeIncludes(kDiagnosticsFilterArgs, StringPrototypeSlice(comment, 0, firstSpaceIndex));
   }
   #handleReportItem(item) {
+    // The name is empty when a single child process runs all test files.
+    if (this.name !== '') {
+      item.data.entryFile = this.loc.file;
+    }
     const isTopLevel = item.data.nesting === 0;
     if (isTopLevel) {
       if (item.type === 'test:plan' && this.#skipReporting()) {

diff --git a/test/fixtures/test-runner/entry-file/a.test.mjs b/test/fixtures/test-runner/entry-file/a.test.mjs
@@ -0,0 +1,3 @@
+import { test } from 'node:test';
+import { runShared } from './helper.mjs';
+test('backup A', async (t) => { await runShared(t, 'A'); });
diff --git a/test/fixtures/test-runner/entry-file/b.test.mjs b/test/fixtures/test-runner/entry-file/b.test.mjs
@@ -0,0 +1,3 @@
+import { test } from 'node:test';
+import { runShared } from './helper.mjs';
+test('backup B', async (t) => { await runShared(t, 'B'); });
diff --git a/test/fixtures/test-runner/entry-file/helper.mjs b/test/fixtures/test-runner/entry-file/helper.mjs
@@ -0,0 +1,3 @@
+export async function runShared(t, target) {
+  await t.test(`restore ${target}`, async () => {});
+}
diff --git a/test/parallel/test-runner-entry-file.mjs b/test/parallel/test-runner-entry-file.mjs
@@ -0,0 +1,59 @@
+import '../common/index.mjs';
+import * as fixtures from '../common/fixtures.mjs';
+import { describe, it, run } from 'node:test';
+import assert from 'node:assert';
+
+const aPath = fixtures.path('test-runner', 'entry-file', 'a.test.mjs');
+const bPath = fixtures.path('test-runner', 'entry-file', 'b.test.mjs');
+const helperPath = fixtures.path('test-runner', 'entry-file', 'helper.mjs');
+
+async function collectEvents(options) {
+  const events = [];
+  const stream = run({ files: [aPath, bPath], ...options });
+  stream.on('test:fail', () => {});
+  for await (const event of stream) {
+    events.push(event);
+  }
+  return events;
+}
+
+describe('entryFile attribution in reporter events', { concurrency: false }, () => {
+  it('stamps entryFile on events forwarded from child processes', async () => {
+    const events = await collectEvents({ isolation: 'process' });
+    const checked = { __proto__: null, A: 0, B: 0 };
+
+    for (const { type, data } of events) {
+      if (data?.name === 'restore A' || data?.name === 'restore B') {
+        const target = data.name === 'restore A' ? 'A' : 'B';
+        const expectedEntry = target === 'A' ? aPath : bPath;
+        assert.strictEqual(data.file, helperPath,
+                           `${type} file should be the definition site`);
+        assert.strictEqual(data.entryFile, expectedEntry,
+                           `${type} entryFile should be the entry file`);
+        checked[target]++;
+      }
+    }
+
+    // Each subtest emits at least enqueue/dequeue/start/pass/complete.
+    assert.ok(checked.A >= 4, `expected events for restore A, got ${checked.A}`);
+    assert.ok(checked.B >= 4, `expected events for restore B, got ${checked.B}`);
+  });
+
+  it('stamps entryFile on top-level tests forwarded from child processes', async () => {
+    const events = await collectEvents({ isolation: 'process' });
+    const pass = events.filter(({ type }) => type === 'test:pass');
+    const backupA = pass.find(({ data }) => data.name === 'backup A');
+    const backupB = pass.find(({ data }) => data.name === 'backup B');
+    assert.strictEqual(backupA.data.entryFile, aPath);
+    assert.strictEqual(backupB.data.entryFile, bPath);
+  });
+
+  it('does not stamp entryFile with isolation none', async () => {
+    const events = await collectEvents({ isolation: 'none' });
+    for (const { data } of events) {
+      if (data?.name === 'restore A' || data?.name === 'restore B') {
+        assert.strictEqual(data.entryFile, undefined);
+      }
+    }
+  });
+});
diff --git a/test/parallel/test-runner-v8-deserializer.mjs b/test/parallel/test-runner-v8-deserializer.mjs
@@ -5,6 +5,7 @@ import { describe, it, beforeEach } from 'node:test';
 import assert from 'node:assert';
 import { finished } from 'node:stream/promises';
 import { DefaultSerializer } from 'node:v8';
+import { resolve } from 'node:path';
 import serializer from 'internal/test_runner/reporter/v8-serializer';
 import runner from 'internal/test_runner/runner';
 
@@ -14,10 +15,15 @@ async function toArray(chunks) {
   return arr;
 }
 
+const entryFile = resolve('filetest');
 const diagnosticEvent = {
   type: 'test:diagnostic',
   data: { nesting: 0, details: {}, message: 'diagnostic' },
 };
+const reportedDiagnosticEvent = {
+  type: 'test:diagnostic',
+  data: { ...diagnosticEvent.data, entryFile },
+};
 const chunks = await toArray(serializer([diagnosticEvent]));
 const defaultSerializer = new DefaultSerializer();
 defaultSerializer.writeHeader();
@@ -67,28 +73,28 @@ describe('v8 deserializer', common.mustCall(() => {
   it('should deserialize a chunk with no serialization', async () => {
     const reported = await collectReported([Buffer.from('unknown')]);
     assert.deepStrictEqual(reported, [
-      { data: { __proto__: null, file: 'filetest', message: 'unknown' }, type: 'test:stdout' },
+      { data: { __proto__: null, entryFile, file: 'filetest', message: 'unknown' }, type: 'test:stdout' },
     ]);
   });
 
   it('should deserialize a serialized chunk', async () => {
     const reported = await collectReported(chunks);
-    assert.deepStrictEqual(reported, [diagnosticEvent]);
+    assert.deepStrictEqual(reported, [reportedDiagnosticEvent]);
   });
 
   it('should deserialize a serialized chunk after non-serialized chunk', async () => {
     const reported = await collectReported([Buffer.concat([Buffer.from('unknown'), ...chunks])]);
     assert.deepStrictEqual(reported, [
-      { data: { __proto__: null, file: 'filetest', message: 'unknown' }, type: 'test:stdout' },
-      diagnosticEvent,
+      { data: { __proto__: null, entryFile, file: 'filetest', message: 'unknown' }, type: 'test:stdout' },
+      reportedDiagnosticEvent,
     ]);
   });
 
   it('should deserialize a serialized chunk before non-serialized output', async () => {
     const reported = await collectReported([Buffer.concat([ ...chunks, Buffer.from('unknown')])]);
     assert.deepStrictEqual(reported, [
-      diagnosticEvent,
-      { data: { __proto__: null, file: 'filetest', message: 'unknown' }, type: 'test:stdout' },
+      reportedDiagnosticEvent,
+      { data: { __proto__: null, entryFile, file: 'filetest', message: 'unknown' }, type: 'test:stdout' },
     ]);
   });
 
@@ -131,7 +137,7 @@ describe('v8 deserializer', common.mustCall(() => {
       oversizedLengthHeader,
       ...chunks,
     ]);
-    assert.deepStrictEqual(reported.at(-1), diagnosticEvent);
+    assert.deepStrictEqual(reported.at(-1), reportedDiagnosticEvent);
     assert.strictEqual(reported.filter((event) => event.type === 'test:diagnostic').length, 1);
     assert.strictEqual(collectStdout(reported), oversizedLengthStdout);
   });
@@ -152,7 +158,7 @@ describe('v8 deserializer', common.mustCall(() => {
       const data = chunks[0];
       const reported = await collectReported([data.subarray(0, i), data.subarray(i)]);
       assert.deepStrictEqual(reported, [
-        diagnosticEvent,
+        reportedDiagnosticEvent,
       ]);
     });
 
@@ -163,9 +169,9 @@ describe('v8 deserializer', common.mustCall(() => {
         Buffer.concat([data.subarray(i), Buffer.from('unknown')]),
       ]);
       assert.deepStrictEqual(reported, [
-        { data: { __proto__: null, file: 'filetest', message: 'unknown' }, type: 'test:stdout' },
-        diagnosticEvent,
-        { data: { __proto__: null, file: 'filetest', message: 'unknown' }, type: 'test:stdout' },
+        { data: { __proto__: null, entryFile, file: 'filetest', message: 'unknown' }, type: 'test:stdout' },
+        reportedDiagnosticEvent,
+        { data: { __proto__: null, entryFile, file: 'filetest', message: 'unknown' }, type: 'test:stdout' },
       ]);
     }
     );