Fix crash in lerna version when using gitSignTag

[squidfunk]

When instructing lerna to sign tags, gpg often runs out of memory because it isn't designed to be run in parallel (see similar issue on another repository). Thus, when signGitTag is set to true, signing must be carried out serially.

Description

If gitTagSign is set to true, this PR will sign tags one after another, omitting the race condition

Motivation and Context

Signing git tags

How Has This Been Tested?

I'm not sure how to test it, as we'd need to somehow mock gitTag to check if we call it concurrently or not.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Chore (change that has absolutely no effect on users)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

Possibly related

• lerna version - "error: unable to sign the tag" #2554

[fahslaj]

Hi @squidfunk , do you happen to have a public repo that this error occurs in? I created a small test repo and set up gpg locally and was not able to reproduce the issue you describe.

[squidfunk]

Thanks for investigating. I don't currently have a public repo exposing this behavior. The problem only occurs sporadically, and you need to have several CPUs available and run lerna version concurrently on several packages so that tags are signed in parallel. I believe it's a race condition. Let me try to create a reproduction.

[fahslaj]

@squidfunk Thank you for the extra context. I tested this on a larger repo with many packages and was able to reproduce the issue after all and confirm that the proposed solution fixes it. I've pushed a small formatting change and will merge this as soon as CI passes.

[fahslaj]

Thanks @squidfunk !

[squidfunk]

Perfect! Thanks for the quick merge! Sorry that I wasn't more responsive, I had some other things on my plate today, but glad you could reproduce the problem ☺️ Next time I will provide a reproduction right away.