Problem:
The LSP omnifunc can insert nil bytes, which when read in other places
(like semantic token) could cause an error:
semantic_tokens.lua:304: Vim:E976: Using a Blob as a String
Solution:
Use `#line` instead of `vim.fn.strlen(line)`. Both return UTF-8 bytes
but the latter can't handle nil bytes.
Completion candidates can currently insert nil bytes, if other parts of
Alternative fix to https://github.com/neovim/neovim/pull/30359
Note that https://github.com/neovim/neovim/pull/30315 will avoid the
insertion of nil bytes from the LSP omnifunc, but the change of this PR
can more easily be backported.
8512f669f0
