[cknitt]

Fixes #9241.

• Failed first build cleans every later build: already fixed on master by Replace lib/bs and lib/ocaml with a flat lib/rescript #9245, which writes compiler-info.json as soon as the clean decision is made; run.sh covers it.
• clean during watch: rescript clean now takes the watch lock of the folder it cleans, as rescript watch does, and refuses while a watcher runs:

  Could not clean while rescript watch or another clean is running. The process ID (PID) is 4242
  

  A watcher still takes its lock before reading the configuration, so a clean of a whole workspace does not see a watcher started in one of its members.

New test: check_command_validation.sh runs clean against a running watcher, expects the refusal with the artifacts left in place, and checks that the watcher still rebuilds.

🤖 Generated with Claude Code

https://claude.ai/code/session_01Kbf3gGBR9g3DD93vrWbYzU

[github-actions]

Changelog

🐛 Bug fix

• rescript clean refuses while rescript watch runs for the same project, instead of removing the artifacts the watcher keeps reading.

Semantic Diff

1 commit · Full page

Refuse to clean while a watcher of the project runs

_{323c05f · cknitt + Claude · Nov 06, 2026, 20:31 UTC}

Why

rescript clean took only the build lock, which a watcher holds only while it builds, so a clean during rescript watch removed the artifacts the watcher kept reading, and every later rebuild failed (#9241).

Diagnostic added (rescript clean while rescript watch runs)

text

-Cleaning x, exit 0; the watcher then fails with Sys_error("<root>/lib/rescript/A.ast: No such file or directory")
+exit 1; the artifacts and the watcher are left as they were

diagnostic · After

Could not clean while rescript watch or another clean is running. The process ID (PID) is 4242

Clean now takes the watch lock of the folder it cleans, as rescript watch does, before the build lock.

Review

• Does a clean of a workspace see a watcher of one of its members? No: each takes the watch lock of the folder it was given, and a watcher takes it before it reads the configuration, which a test requires.

[cknitt]

@codex review

[chatgpt-codex-connector]

Codex Review Summary: ✅ Completed

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-11-06T21:16:58.301220Z	323c05f	Manual request

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review" or "@codex security review".

Codex reacts with 👀 while any review is running, comments if it has suggestions, and reacts with 👍 once all reviews finish with no findings.

[chatgpt-codex-connector]

Codex Review: Didn't find any major issues. 👍

Reviewed commit: 323c05facf

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

If Codex has suggestions, it will comment; otherwise it will react with 👍.

Codex can also answer questions or update the PR. Try commenting "@codex address that feedback".

[pkg-pr-new]

Open in StackBlitz

rescript

npm i https://pkg.pr.new/rescript@9247

@rescript/belt

npm i https://pkg.pr.new/@rescript/belt@9247

@rescript/darwin-arm64

npm i https://pkg.pr.new/@rescript/darwin-arm64@9247

@rescript/linux-arm64

npm i https://pkg.pr.new/@rescript/linux-arm64@9247

@rescript/linux-x64

npm i https://pkg.pr.new/@rescript/linux-x64@9247

@rescript/runtime

npm i https://pkg.pr.new/@rescript/runtime@9247

@rescript/win32-x64

npm i https://pkg.pr.new/@rescript/win32-x64@9247

commit: 323c05f

[github-actions]

Developer playground preview: https://rescript-lang.github.io/rescript/dev-playground/?version=pr-9247