Help diagnosing lack of inactive region highlighting with coc-clangd

[mellery451]

I'm trying to figure out why my inactive regions are not showing as such (lowlighted as comments).

My setup:

 NVIM v0.5.0-2ca8f02a6
 or 
 VIM - Vi IMproved 8.2
 clangd version 10.0.0
 coc.nvim, coc-clangd, and vim-lsp-cxx-highlight are up-to-date

CocInfo:

## Output channel: highlight

[Info  - 5:35:02 PM] Highlight server running in node v14.4.0

## Output channel: clangd log

[17:35:06.092] clangd version 10.0.0
[17:35:06.092] PID: 12415
[17:35:06.092] Working directory: /home/xxxx
[17:35:06.092] argv[0]: /home/linuxbrew/.linuxbrew/bin/clangd
[17:35:06.092] argv[1]: --background-index
[17:35:06.092] argv[2]: --clang-tidy
[17:35:06.092] argv[3]: -j=3
[17:35:06.092] Starting LSP over stdin/stdout
[17:35:06.093] <-- initialize(0)
[17:35:06.093] --> reply:initialize(0) 0 ms
[17:35:06.094] <-- initialized
[17:35:06.094] unhandled notification initialized
[17:35:06.095] <-- textDocument/didOpen
[17:35:06.945] Enqueueing 0 commands for indexing
[17:35:06.987] --> textDocument/clangd.fileStatus
[17:35:06.987] Updating file /home/xxxxx/File.cpp with command inferred from zzzz/other.cpp   g++ ......
[17:35:08.652] --> textDocument/publishDiagnostics
[17:35:08.654] --> textDocument/semanticHighlighting
[17:35:08.655] --> textDocument/clangd.fileStatus

cxx-highlight verbose log:

Wed 01 Jul 2020 05:16:20 PM PDT: lsp_cxx_hl beginning initialization...
Wed 01 Jul 2020 05:16:20 PM PDT: vim-lsp not detected
Wed 01 Jul 2020 05:16:20 PM PDT: LanguageClient-neovim not detected
Wed 01 Jul 2020 05:16:20 PM PDT: coc.nvim successfully registered
Wed 01 Jul 2020 05:16:20 PM PDT: nvim-lsp successfully registered
Wed 01 Jul 2020 05:16:30 PM PDT: textprop nvim notify symbols for tests/image/ImageStreamerTest.cpp
Wed 01 Jul 2020 05:16:30 PM PDT: hl_symbols (textprop nvim) highlighted 415 symbols in file xxx/yyy/FILE.cpp
Wed 01 Jul 2020 05:16:30 PM PDT: operation hl_symbols (textprop nvim) xxx/File.cpp took 0.018496s to complete

I can confirm that some token highlighting is happening (enums and such), but the inactive preprocessor regions are not being lowlighted. What else could I look at to diagnose? FWIW some of the code I'm looking at are #if/#else, so even if my compile flags were wrong, ONE of those regions should be inactive. Advice appreciated.

[mellery451]

I just did an additional test myself and enabled ccls along with clangd...now I have lowlighting of inactive regions. So I guess it's clangd 10 that is the problem - perhaps this feature is not yet available or will only be released in 11. I will close this now

[mellery451]

I'm reopening this issue for help specifically figuring out why inactive regions are not showing with clangd. When I change my coc config to enable ccls also, I see the inactive regions - so it's not a matter of incorrect colorscheme at least. When I use ONLY clangd (via coc-clangd), the inactive regions are never shown. I do see other semantic highlights going on, so I'm not sure what I need to debug to figure out what's broken. Is this likely a clangd problem, or an initialization problem perhaps?

[mellery451]

also, I should mention that clangd is idle after the first few semantic hightlights show-up, so I don't think it's a matter of waiting longer for clangd to complete some indexing..in-fact, clangd is really fast on my system and never seems to be doing much in the background.

[bartlibert]

This seems to be related: https://github.com/clangd/clangd/issues/132

[0rtz]

Im using coc.nvim + coc-clangd with clangd version 11.0.0 and can not get highlighting of inactive regions in macros to work aswell, those code regions just do not get LspCxxHlSkippedRegion highlight group, that's unfortunate

[srs-ch]

Looks inactive preprocessor regions are highlighted as comments in Clangd 12.0 and I still can't get highlighting of inactive regions in macros to work.

Semantic highlighting

 Inactive preprocessor regions (#ifdef) are highlighted as comments.
 clangd 12 is the last release with support for the non-standard textDocument/semanticHighlights notification. 
 Clients should migrate to the textDocument/semanticTokens request added in LSP 3.16.