test_runner: support coverage with isolation:'none' via run() API

[Han5991]

Summary

Fixes#60023.

run({ coverage: true, isolation: 'none' }) returned an empty file list because V8 precise coverage is only enabled at bootstrap when NODE_V8_COVERAGE or --experimental-test-coverage is set, neither of which the API path requires. The reporter also surfaced a related inconsistency: with isolation: 'process', test files (e.g. foo.test.mjs) appeared in the coverage report via the API path, while the CLI path excluded them by default.

This PR fixes both halves:

• Coverage now collects on the parent isolate when run() is the entry point. A new profiler.startCoverage() internal binding enables V8 precise coverage at run() time. It is idempotent against the existing bootstrap path and a no-op when the inspector is unavailable (the parent of --test --test-isolation=process, where workers handle coverage themselves).
• Default test-file exclusion is applied consistently across CLI and API paths. When coverage: true is passed to run() without coverageExcludeGlobs, [kDefaultPattern] is applied — matching parseCommandLine's behavior. Two existing run() coverage tests that depended on the absent default are updated to opt out via coverageExcludeGlobs: '!test/**'.

Test plan

• New regression test test/parallel/test-runner-coverage-isolation-none-api.mjs passes — covers isolation=none reports src files, default exclusion drops *.test.mjs in both isolation modes, and idempotency under --experimental-test-coverage.
• All 70 parallel/test-runner-* tests pass.
• Full tools/test.py suite passes; unrelated FFI fixture-build setup and watch-mode flakiness verified independent of this change.
• Issue's original reproduction yields identical, correct coverage in both isolation modes (src file present, test file excluded by default).

Refs: #60023

[nodejs-github-bot]

Review requested:

• @nodejs/inspector
• @nodejs/test_runner

[codecov]

Codecov Report

❌ Patch coverage is 82.35294% with 3 lines in your changes missing coverage. Please review.
✅ Project coverage is 89.74%. Comparing base (e80b5d2) to head (2851a03).
⚠️ Report is 181 commits behind head on main.

Files with missing lines	Patch %	Lines
src/inspector_profiler.cc	76.92%	2 Missing and 1 partial ⚠️

Additional details and impacted files

@@ Coverage Diff @@## main #63079 +/- ##
==========================================
+ Coverage 89.66% 89.74% +0.08% 
==========================================
Files 713 713 Lines 224076 224250 +174 Branches 42308 42407 +99 ==========================================
+ Hits 200912 201263 +351 + Misses 14996 14815 -181 - Partials 8168 8172 +4 

Files with missing lines	Coverage Δ
lib/internal/test_runner/coverage.js	67.57% <100.00%> (+3.38%)	⬆️
lib/internal/test_runner/runner.js	93.77% <100.00%> (+0.10%)	⬆️
src/inspector_profiler.cc	82.19% <76.92%> (-0.18%)	⬇️

... and 60 files with indirect coverage changes

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• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
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[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/73516/

[nodejs-github-bot]

Commit Queue failed

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----------------------------------- PR info ------------------------------------
Title test_runner: support coverage with isolation:'none' via run() API (#63079)
Author sangwook <rewq5991@gmail.com> (@Han5991)
Branch Han5991:fix/test-runner-coverage-isolation-none -> nodejs:main
Labels c++, semver-minor, lib / src, needs-ci
Commits 5
- inspector: expose precise coverage start to JS runtime
- test_runner: enable coverage on run() with isolation: 'none'
- test_runner: apply default test-file exclusion via run() API
- test: add coverage tests for run() with isolation: 'none'
- test: use fixture for isolation=none coverage runner script
Committers 1
- sangwook <rewq5991@gmail.com>
PR-URL: https://github.com/nodejs/node/pull/63079
Refs: https://github.com/nodejs/node/issues/60023
Reviewed-By: Chemi Atlow <chemi@atlow.co.il>
Reviewed-By: Pietro Marchini <pietro.marchini94@gmail.com>
Reviewed-By: Aviv Keller <me@aviv.sh>
------------------------------ Generated metadata ------------------------------
PR-URL: https://github.com/nodejs/node/pull/63079
Refs: https://github.com/nodejs/node/issues/60023
Reviewed-By: Chemi Atlow <chemi@atlow.co.il>
Reviewed-By: Pietro Marchini <pietro.marchini94@gmail.com>
Reviewed-By: Aviv Keller <me@aviv.sh>
--------------------------------------------------------------------------------
ℹ This PR was created on Sat, 02 May 2026 06:49:36 GMT
✔ Approvals: 3
✔ - Chemi Atlow (@atlowChemi): https://github.com/nodejs/node/pull/63079#pullrequestreview-4278650896
✔ - Pietro Marchini (@pmarchini): https://github.com/nodejs/node/pull/63079#pullrequestreview-4217842569
✔ - Aviv Keller (@avivkeller): https://github.com/nodejs/node/pull/63079#pullrequestreview-4231403222
✔ Last GitHub CI successful
ℹ Last Full PR CI on 2026-05-17T23:55:40Z: https://ci.nodejs.org/job/node-test-pull-request/73516/
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- Bringing origin/main up to date...
From https://github.com/nodejs/node
* branch main -> FETCH_HEAD
✔ origin/main is now up-to-date
- Downloading patch for 63079
From https://github.com/nodejs/node
* branch refs/pull/63079/merge -> FETCH_HEAD
✔ Fetched commits as 8d3245e551eb..2851a032b53a
--------------------------------------------------------------------------------
[main f5b791804a] inspector: expose precise coverage start to JS runtime
Author: sangwook <rewq5991@gmail.com>
Date: Sat May 2 15:45:11 2026 +0900
1 file changed, 26 insertions(+)
[main b8f1d34ecb] test_runner: enable coverage on run() with isolation: 'none'
Author: sangwook <rewq5991@gmail.com>
Date: Sat May 2 15:45:16 2026 +0900
1 file changed, 2 insertions(+)
Auto-merging lib/internal/test_runner/runner.js
[main 2d05602984] test_runner: apply default test-file exclusion via run() API
Author: sangwook <rewq5991@gmail.com>
Date: Sat May 2 15:45:24 2026 +0900
2 files changed, 11 insertions(+), 1 deletion(-)
[main b6a95ad624] test: add coverage tests for run() with isolation: 'none'
Author: sangwook <rewq5991@gmail.com>
Date: Sat May 2 15:45:35 2026 +0900
3 files changed, 114 insertions(+)
create mode 100644 test/fixtures/test-runner/coverage-isolation-none/src/foo.mjs
create mode 100644 test/fixtures/test-runner/coverage-isolation-none/tests/foo.test.mjs
create mode 100644 test/parallel/test-runner-coverage-isolation-none-api.mjs
[main 9d4de8f8c1] test: use fixture for isolation=none coverage runner script
Author: sangwook <rewq5991@gmail.com>
Date: Wed May 6 06:26:00 2026 +0900
2 files changed, 20 insertions(+), 23 deletions(-)
create mode 100644 test/fixtures/test-runner/coverage-isolation-none/runner.mjs
✔ Patches applied
There are 5 commits in the PR. Attempting autorebase.
(node:396) [DEP0190] DeprecationWarning: Passing args to a child process with shell option true can lead to security vulnerabilities, as the arguments are not escaped, only concatenated.
(Use `node --trace-deprecation ...` to show where the warning was created)
Rebasing (2/10)
�[KExecuting: git node land --amend --yes

⚠ Found Refs: https://github.com/nodejs/node/issues/60023, skipping..

--------------------------------- New Message ----------------------------------

inspector: expose precise coverage start to JS runtime
Add a startCoverage method on the profiler internal binding so

that V8 precise coverage can be enabled after bootstrap. The method

is idempotent against the existing bootstrap path (which creates a

V8CoverageConnection when NODE_V8_COVERAGE or

--experimental-test-coverage is set) and a no-op when the inspector

is unavailable, e.g. in the parent process of
--test --test-isolation=process where workers handle coverage and

Environment::should_create_inspector() returns false.
Refs: #60023

Signed-off-by: sangwook <rewq5991@gmail.com>

PR-URL: #63079

Reviewed-By: Chemi Atlow <chemi@atlow.co.il>

Reviewed-By: Pietro Marchini <pietro.marchini94@gmail.com>

Reviewed-By: Aviv Keller <me@aviv.sh>
[detached HEAD 6075330b15] inspector: expose precise coverage start to JS runtime

Author: sangwook <rewq5991@gmail.com>

Date: Sat May 2 15:45:11 2026 +0900

1 file changed, 26 insertions(+)

Rebasing (3/10)

Rebasing (4/10)
�[KExecuting: git node land --amend --yes

--------------------------------- New Message ----------------------------------

test_runner: enable coverage on run() with isolation: 'none'
run({ coverage: true, isolation: 'none' }) previously returned an

empty file list because V8 precise coverage is only started at

bootstrap when NODE_V8_COVERAGE or --experimental-test-coverage is

set, neither of which the API path requires. Call the new

profiler.startCoverage() binding from setupCoverage() so the parent

isolate is instrumented when the run() API is the entry point.
Fixes: #60023

Signed-off-by: sangwook <rewq5991@gmail.com>

PR-URL: #63079

Refs: #60023

Reviewed-By: Chemi Atlow <chemi@atlow.co.il>

Reviewed-By: Pietro Marchini <pietro.marchini94@gmail.com>

Reviewed-By: Aviv Keller <me@aviv.sh>
[detached HEAD 6815687774] test_runner: enable coverage on run() with isolation: 'none'

Author: sangwook <rewq5991@gmail.com>

Date: Sat May 2 15:45:16 2026 +0900

1 file changed, 2 insertions(+)

Rebasing (5/10)

Rebasing (6/10)
�[KExecuting: git node land --amend --yes

⚠ Found Refs: https://github.com/nodejs/node/issues/60023, skipping..

--------------------------------- New Message ----------------------------------

test_runner: apply default test-file exclusion via run() API
The CLI path defaults coverageExcludeGlobs to [kDefaultPattern] when

--experimental-test-coverage is set, dropping test files from the

coverage report. The run() API skipped this default, so callers got

test files mixed into their coverage data. Apply the same default

when run() is invoked with coverage: true and no explicit

coverageExcludeGlobs, so both entry points behave consistently.
Update the existing run() coverage tests that depended on the absent

default to opt out via coverageExcludeGlobs: '!test/**'.
Refs: #60023

Signed-off-by: sangwook <rewq5991@gmail.com>

PR-URL: #63079

Reviewed-By: Chemi Atlow <chemi@atlow.co.il>

Reviewed-By: Pietro Marchini <pietro.marchini94@gmail.com>

Reviewed-By: Aviv Keller <me@aviv.sh>
[detached HEAD 79b919dfb5] test_runner: apply default test-file exclusion via run() API

Author: sangwook <rewq5991@gmail.com>

Date: Sat May 2 15:45:24 2026 +0900

2 files changed, 11 insertions(+), 1 deletion(-)

Rebasing (7/10)

Rebasing (8/10)
�[KExecuting: git node land --amend --yes

⚠ Found Refs: https://github.com/nodejs/node/issues/60023, skipping..

--------------------------------- New Message ----------------------------------

test: add coverage tests for run() with isolation: 'none'
Verify that:
run({ coverage: true, isolation: 'none' }) reports src files,
default test-file exclusion drops *.test.mjs in both isolation

modes,
the path is idempotent when --experimental-test-coverage is set

on the same process.
Refs: #60023

Signed-off-by: sangwook <rewq5991@gmail.com>

PR-URL: #63079

Reviewed-By: Chemi Atlow <chemi@atlow.co.il>

Reviewed-By: Pietro Marchini <pietro.marchini94@gmail.com>

Reviewed-By: Aviv Keller <me@aviv.sh>
[detached HEAD c3ff4adfb0] test: add coverage tests for run() with isolation: 'none'

Author: sangwook <rewq5991@gmail.com>

Date: Sat May 2 15:45:35 2026 +0900

3 files changed, 114 insertions(+)

create mode 100644 test/fixtures/test-runner/coverage-isolation-none/src/foo.mjs

create mode 100644 test/fixtures/test-runner/coverage-isolation-none/tests/foo.test.mjs

create mode 100644 test/parallel/test-runner-coverage-isolation-none-api.mjs

Rebasing (9/10)

Rebasing (10/10)
�[KExecuting: git node land --amend --yes

--------------------------------- New Message ----------------------------------

test: use fixture for isolation=none coverage runner script
PR-URL: #63079

Refs: #60023

Reviewed-By: Chemi Atlow <chemi@atlow.co.il>

Reviewed-By: Pietro Marchini <pietro.marchini94@gmail.com>

Reviewed-By: Aviv Keller <me@aviv.sh>
[detached HEAD 5806e3e6d6] test: use fixture for isolation=none coverage runner script

Author: sangwook <rewq5991@gmail.com>

Date: Wed May 6 06:26:00 2026 +0900

2 files changed, 20 insertions(+), 23 deletions(-)

create mode 100644 test/fixtures/test-runner/coverage-isolation-none/runner.mjs
�[KSuccessfully rebased and updated refs/heads/main.
ℹ Add commit-queue-squash label to land the PR as one commit, or commit-queue-rebase to land as separate commits.

https://github.com/nodejs/node/actions/runs/26330521863

[nodejs-github-bot]

Landed in c9dbb86