Providers should return undefined

[LenKrause]

Providers should return undefined instead of an empty list to allow other providers to continue

[StephanWald]

Thanks for the PR! The change makes sense — returning undefined lets other providers contribute when field completion offers nothing.

One thing to consider: with this change, typing # outside a class method will now fall through to the default Langium completion provider (keywords, references, etc.). Previously the empty list would short-circuit that. Is that the behavior you're after?

For context, we intentionally kept the ( trigger path returning an empty list (line 28) to prevent exactly that kind of
slow fallthrough — so this creates an asymmetry between the two trigger characters. If the fallthrough after # outside
class methods is desirable, it might be worth adding a comment explaining why # and ( behave differently.

[LenKrause]

Stephan- Our extension also provides completion after a # entry when inside a class method.   It stopped working after a recent upgrade of your extension.  I tracked it down to the code changes proposed. When multiple providers in the same or different extensions return something, VS Code will show all responses.  But returning an empty list means quit checking other providers so our code is not executed. As your extension evolves, we may be able to remove our response to a # entry, but for a long time it has been necessary. -Len On Sun, Mar 29, 2026 at 11:55 AM Stephan Wald ***@***.***> wrote: StephanWald left a comment (BBx-Kitchen/bbj-language-server#383) Thanks for the PR! The change makes sense — returning undefined lets other providers contribute when field completion offers nothing. One thing to consider: with this change, typing # outside a class method will now fall through to the default Langium completion provider (keywords, references, etc.). Previously the empty list would short-circuit that. Is that the behavior you're after? For context, we intentionally kept the ( trigger path returning an empty list (line 28) to prevent exactly that kind of slow fallthrough — so this creates an asymmetry between the two trigger characters. If the fallthrough after # outside class methods is desirable, it might be worth adding a comment explaining why # and ( behave differently. — Reply to this email directly, view it on GitHub, or unsubscribe. You are receiving this because you authored the thread.Message ID: ***@***.***>