Skip package management if running in github-hosted container

[punchagan]

GitHub allows running actions in containers 1 on the runners, and when
using a non apt-based Linux distribution, setup-ocaml doesn't work
correctly. This commit skips package management on docker containers,
similar to the behavior on self-hosted runners.

[punchagan]

Alternatively, we could also allow using an environment variable (or an input config value?) to allow skipping package management.

[smorimoto]

@punchagan Is current code OK for you?

[punchagan]

@smorimoto Thanks for reviewing the PR!

@punchagan Is current code OK for you?

No, the current code checks for the .dockerenv in the current working directory, but my original PR was looking for /.dockerenv. This is not documented but something I found from the example in the documentation page and it seems to work - see a sample build here with the corresponding workflow file. This is a failing build with the current code in this PR.

[punchagan]

@smorimoto I pushed a small change to change the path to /.dockerenv instead of ${PWD}/.dockerenv. I've also added a container based run to the workflow GitHub action to test this workflow with any future changes too.

diff --git a/packages/setup-ocaml/src/unix.ts b/packages/setup-ocaml/src/unix.ts
index 532cffce..19aba5bc 100644
--- a/packages/setup-ocaml/src/unix.ts
+++ b/packages/setup-ocaml/src/unix.ts
@@ -1,6 +1,5 @@
 import * as fs from "node:fs/promises";
 import * as path from "node:path";
-import * as process from "node:process";
 import { exec, getExecOutput } from "@actions/exec";
 import { PLATFORM, RUNNER_ENVIRONMENT } from "./constants.js";
 
@@ -39,7 +38,7 @@ async function skipPackageManagement() {
   // github-hosted Docker container.
   let isContainerRunner = false;
   try {
-    const dockerenv = path.join(process.cwd(), ".dockerenv");
+    const dockerenv = path.join("/", ".dockerenv");
     await fs.access(dockerenv, fs.constants.R_OK);
     isContainerRunner = true;
   } catch {

[smorimoto]

Oops, indeed.

[Copilot]

Pull Request Overview

This PR enhances the OCaml setup action to skip system package management when running in GitHub-hosted Docker containers (or self-hosted runners) and updates CI to test in an Arch Linux container.

• Added skipPackageManagement() to detect Docker containers and self-hosted environments.
• Updated installUnixSystemPackages and updateUnixPackageIndexFiles to call the new skip helper.
• Extended CI with an archlinux container job and SSL setup in the workflow.

Reviewed Changes

Copilot reviewed 2 out of 3 changed files in this pull request and generated no comments.

File	Description
packages/setup-ocaml/src/unix.ts	Introduced skipPackageManagement and replaced self-hosted checks
.github/workflows/workflow.yml	Added test-container job and SSL install step to CI workflow

Comments suppressed due to low confidence (4)

packages/setup-ocaml/src/unix.ts:35

• [nitpick] There are no tests covering skipPackageManagement. Add unit tests for both container and non-container scenarios to verify the skip logic.

async function skipPackageManagement() {

.github/workflows/workflow.yml:65

• This run step is indented under the with block rather than at the job step level. It needs to be unindented to align with other steps so the workflow executes correctly.

      - run: opam install ssl

.github/workflows/workflow.yml:67

• The test-container job lacks a step to install the ssl package via opam, which may cause failures. Add a - run: opam install ssl after setting up OCaml.

  test-container:

packages/setup-ocaml/src/unix.ts:1

• fs.constants isn’t exported from the promises-only import, so fs.constants.R_OK will be undefined at runtime. Import constants from 'node:fs' or switch to import * as fs from 'node:fs'.

import * as fs from "node:fs/promises";

[punchagan]

Thank you for the review, the code improvements and the merge! 🎉

[punchagan]

@smorimoto Is it possible to also publish a release with this change?

[smorimoto]

I'm on the plane now, so I'll do it later!

[punchagan]

I'm on the plane now, so I'll do it later!

Okay, thank you! Have a safe flight!

[smorimoto]

Done!