Suggestions for implementing interface methods only appear at the beginning.

[gavr123456789]

Suggestions for implementing interface methods only appear at the beginning of class body.

GIF:

[Prince781]

This is an issue that comes up because of the way the Vala compiler establishes the source reference for a class declaration's Vala.Scope (it only covers the SRs of the declared members, not necessarily up to the closing brace). I think I asked @ricotz about it and I forgot the reason why he was against changing the behavior.

There's also a related issue here: VLS's rapid completion happens before the document is recompiled, so currently we just assume all scopes are one line longer than they really are. This approach only works if the recompilation is fast enough to happen before the second time you're inserting a new line. I think a refinement to this approach would be to send an incomplete completion list initially and then send an updated list after the document is recompiled. See CompletionList.isIncomplete.