fix: try to infer languageId from extension when invalid provided

[rchl]

Fixup languageId if an invalid one was provided when opening a document.

4.1 version of the server started being more strict about that and stopped accepting invalid languageId. Since this wasn't an intentional breaking change and because it wasn't a major/breaking release, introduce code that automatically infers correct ID from file extension so that there are no disruptions for clients that don't send correct ID.

This compatibility layer will be removed in the next major release.

Fixes #794

[github-actions]

size-limit report 📦

Path	Size
lib/cli.mjs	782.27 KB (+0.11% 🔺)

[HIRANO-Satoshi]

Could you kindly make a quick release with this?

I guess so many users are wasting time to find the reason of failure as we did.

And I would like to ask you not to remove this.

[rchl]

Could you kindly make a quick release with this?

I guess so many users are wasting time to find the reason of failure as we did.

And I would like to ask you not to remove this.

Released now.

Note that, as said in #794 (comment), this is just a stop gap to not break clients that don't send correct languageId and the plan is to remove this stop gap in the next major release (which is likely not gonna be released anytime soon). As said in the linked comment, the proper solution is for clients or client configurations to get updated to send a correct ID.

[HIRANO-Satoshi]

Thanks a lot.

You are right, but it's a fallback.