macOS arm64 + Insiders: `spawn .../Contents/MacOS/Electron ENOENT` (CI reproducer for #349)

[miguelcolmenares]

Summary

On darwin-arm64 GitHub-hosted runners (macos-latest, Apple Silicon), @vscode/test-electron@3.0.0 downloads the VS Code Insiders archive successfully, then fails to launch it:

✔ Downloaded VS Code (07b4ff1883f94da91f6d698744fc7c3638b59720) into
   .vscode-test/vscode-darwin-arm64-insiders
Test error: Error: spawn .../Visual Studio Code - Insiders.app/Contents/MacOS/Electron ENOENT

The same test suite passes on ubuntu-latest + Insiders, windows-latest + Insiders, and every macOS Stable / pinned-version cell on the same commit. The failure is scoped strictly to darwin-arm64 + Insiders.

Root cause

Fully diagnosed in #349 (thanks @aasimkhan30). Summary of that thread as it applies here:

• VS Code renamed the macOS executable from Electron to the product name (Code / Code - Insiders) in microsoft/vscode#291948, merged 2026-02-03, first shipping in 1.110.
• The Electron compatibility symlink was removed in microsoft/vscode#326502, merged 2026-07-20.
• @vscode/test-electron still hardcodes the old Electron path, so any post-symlink-removal build produces the ENOENT above.

darwin-arm64 + Insiders surfaced this first because Insiders leads Stable through both the rename and the symlink removal. The same failure will reach darwin-arm64 + Stable as soon as Stable crosses the 2026-07-20 cutoff.

This issue is the CI-visible reproducer that led me to #349 before the root cause was clear. Keeping it open as the downstream-facing counterpart to #349 so consumers hitting the ENOENT symptom can find the workaround.

Environment

@vscode/test-electron	3.0.0
@vscode/test-cli	0.0.15
Node.js	20.20.2 (also reproduces on 24)
Runner	macos-latest on GitHub Actions (Apple Silicon / darwin-arm64)
VS Code channel	insiders
Downloaded commit	07b4ff1883f94da91f6d698744fc7c3638b59720 (~340 MB archive)

Steps to reproduce

1. Set up a VS Code extension with @vscode/test-cli and a .vscode-test.mjs that supports insiders.
2. Run npm test on a GitHub-hosted macos-latest runner (arm64).
3. Observe: download succeeds, launcher throws ENOENT.

Minimal .vscode-test.mjs:

import { defineConfig } from '@vscode/test-cli';

export default defineConfig({
  files: 'out/test/**/*.test.js',
  version: process.env.VSCODE_VERSION || 'stable', // set VSCODE_VERSION=insiders
});

Minimal workflow step:

- uses: coactions/setup-xvfb@v1
  with:
    run: npm test
  env:
    VSCODE_VERSION: 'insiders'

Reproduction repository

• Repo: https://github.com/miguelcolmenares/css-js-minifier
• Failing run (before workaround): actions/runs/29896038382/job/88846313602
• Same commit, other matrix cells pass: Ubuntu-Insiders, Windows-Insiders, macOS-Stable, Ubuntu-Stable, Windows-Stable, macOS-min (1.125.0).

Workaround currently deployed

Drop macos-latest from the Insiders matrix. macOS arm64 coverage is retained via Stable and minimum-version workflows, both running on macos-latest. Reference implementation: miguelcolmenares/css-js-minifier#175.

Intel-fallback runners (macos-13, macos-15-intel) are not a viable long-term workaround:

• macos-13 was retired 2025-12-04 (actions/runner-images#13046); jobs targeting it queue indefinitely.
• macos-15-intel is a transitional label, retiring Fall 2027 per the 2025-09-19 GitHub Changelog.
• Rosetta 2 is available only through macOS 27 and reduced to legacy games starting with macOS 28 (Apple HT102527).
• @vscode/test-cli's IBaseTestConfiguration does not expose a platform field, so consumers can't force an x64 download on an arm64 host without dropping to @vscode/test-electron's programmatic API.

Ask

Ship the fix proposed in #349: resolve the macOS executable dynamically via CFBundleExecutable / product.nameShort, with Electron as a fallback for pre-1.110 builds. Downstream consumers can then restore macos-latest (arm64) to their Insiders CI matrices without any Intel/Rosetta bridge.

Happy to test a pre-release against the reproducer above.

Related

• @vscode/test-electron uses obsolete macOS executable path #349 — @vscode/test-electron uses obsolete macOS executable path (upstream code defect, same root cause).
• Hangs on Mac mini M2 headless #290 — Hangs on Mac mini M2 headless (same family — Apple Silicon macOS — different symptom).
• runTest uses incorrect platform x64 on arm64  #141 / fix: incorrect platform used on arm64 Linux #145 / Support downloading VS Code arm64 builds on Linux arm64 #133 — Prior arm64 platform fixes in this repo; establishes precedent that darwin-arm64 + Insiders is the missing counterpart.