[Feature request] the hg prompt in cmd is very slow, it doesn't have async prompt support yet

[chrisant996]

Suggestion

Cmder's git prompt uses async prompt filtering in cmd (Clink) to make the prompt show up instantly.

Cmder's hg prompt doesn't use async prompt filtering yet.
Cmder's svn prompt doesn't use async prompt filtering unless a special config variable is set.

This was reported in chrisant996/clink#792 by @luc0x61.

Use case

When the current directory is in a Mercurial or Subversion workspace, then the prompt is slow.

Extra info/examples/attachments

No response

Checklist

• I have read the documentation and made sure this feature doesn't already exist.
• I have searched for similar issues and found none that describe my feature request.

[chrisant996]

I have a fix for these issues, and some other minor bugs in the hg and svn prompts as well.

The PR is here: #3021

[DRSDavidSoft]

Wow, that was fast! 👍🏻

I'll review and merge the PR soon. Thanks for the fixes!

[chrisant996]

I installed both Mercurial and Subversion and tested the PR.

I found one additional pre-existing bug, and I updated this PR with another commit to fix it. When the hg program is not found, then the PR fixed the Lua script error bug, but another bug caused () to be appended to the prompt. It shouldn't append anything in that case, just like the svn prompt doesn't append anything in that case.