Provide context to format provider so it knows whether a format came from a save request/manual invocation

[DanTup]

I have users that need to disable format-on-save for some sub-tree within their project. Since they can't put settings in sub-folders (without making them workspace folders, which duplicates them at the top - see #45470) my plan is to implement a setting where they can configure a list of files (patterns, like files.exclude) to exclude from formatting.

However, it'd be bette if we could exclude them from automatic formatting without making explicit format requests silently fail. Currently it doesn't seem like the format provider is given enough information for this.

[jrieken]

This sounds just like workarounds. what you want is settings in sub folders.

[DanTup]

what you want is settings in sub folders

Yes, that's true! Is it on the cards? (I assumed not, but that would be waaay better)

[sandy081]

/duplicate

#32693

[DanTup]

I think there's actually another reason to have this that settings don't provide.

If a formatter refuses to format invalid code (which seems valid as a misplaced brace could mess everything up), it may be confusing to a user if the formatting request just "doesn't work" without giving some indication of why. Displaying a message seems reasonable.

However, if the format is being run on-save, then showing an error may be somewhat spammy.

The same is true for other commands (I opened microsoft/language-server-protocol#1018 in LSP about this.. right now all my commands tha may be useful to run on-save just fail "silently").