Completion (and renaming) behaves incorrectly on labels with colons

[clason]

Completion on symbols that include colons (such as eq:strong-convergence) can lead to incorrect substitutions. I've originally reported this for vim-lsp (prabirshrestha/vim-lsp#420), but it turns out the issue occurs in VS Code as well (slightly differently).

Here's a minimal example from @thomasfaingnaert:

documentclass{article}

\begin{document}
\section{Foo bar}%
\label{sec:foo_bar}
\ref{sec:foo<cursor here>}
\end{document}

The language server then correctly suggests sec:foo_bar, but when I select it, it inserts it after the initial sec:, i.e., I get sec:sec:foo_bar. (vim-lsp turns that into \ref{sec:barsec:foo_bar} instead.)

The relevant part of the log is

Thu 27 Jun 2019 15:19:36 CEST:["--->",1,"texlab",{"method":"textDocument/completion","on_notification":"---funcref---","params":{"textDocument":{"uri":"file:///home/thomas/test.tex"},"position":{"character":12,"line":5}}}]
Thu 27 Jun 2019 15:19:36 CEST:["<---",1,"texlab",{"response":{"id":41,"jsonrpc":"2.0","result":{"isIncomplete":true,"items":[{"label":"sec:foo_bar","data":"Label","kind":5}]}},"request":{"id":41,"jsonrpc":"2.0","method":"textDocument/completion","params":{"textDocument":{"uri":"file:///home/thomas/test.tex"},"position":{"character":12,"line":5}}}}]

i.e., texlab gives the wrong position. (A related issue is with renaming: if I rename sec:foo_bar, the prefilled text is just foo_bar, but the whole label (including sec:) is replaced with what I write. This is much less critical, of course.)

@thomasfaingnaert suggests not using labels for completions but rather text-edits, which is a newer part of the LSP protocol.

[pfoerster]

@thomasfaingnaert suggests not using labels for completions but rather text-edits, which is a newer part of the LSP protocol.

The server now uses the textEdit field in CompletionItem.
In your example, the completion now works correctly.

(A related issue is with renaming: if I rename sec:foo_bar, the prefilled text is just foo_bar, but the whole label (including sec:) is replaced with what I write. This is much less critical, of course.)

The server now implements the textEdit/prepareRename request so this issue should be fixed as well.

[clason]

Great, thanks!