ifdef/else/`endif folding

[eng-tp]

Hi,

I'm seeing issues with folding whenever ifdef/endif pairs have else or elsif directives in between them.
These issues persist even when defining the foldingStrategy as indentation.
E.g.:

`ifndef COMP_GUARD
`define COMP_GUARD
  class x
    function z
      `ifdef A
        behavior 1
      `else //A
        behavior 2
      `endif //A
    endfunction
  endclass
`endif //COMP_GUARD

• folding on ifdef A folds code all the way to endif //COMP_GUARD, ignoring the middle else //A and endif //A
• folding on else //A folds to endif //A as expected

Looking at the languageSettings.json file for systemverilog, I see that:

1. else and elsif are present in both start and end markers
2. markers for all ifdef - related directives do not assume \b at the beginning (so, no indentation is detected and/or preserved)

I can't say whether any of these is responsible for the indentation failure - but I assume it's the latter -, and I also don't know how I can experiment with this locally: I am a new user to VSCode and its extensions, and it seems I can't edit the languageSettings.json file for the systemverilog extension locally - or I don't know how to do it...

This seems related with #65 , but that issue was closed and this behavior persists.

Can you please help me in figuring this out?

Thanks, and BR

P.S.: all tick chars were removed due to formatting issues, but you get the point :)

[joecrop]

Hi @eng-tp, I dug into this, and it appears to be a limitation of the vscode language configuration. You are right, language-configuration.json is the file that controls folding of ifdefs. Unfortunately, because else is both a begin and end pattern, vscode seems to be greedy and ignore it as an end and skips to endif.

It seems like we would need to implement a registerFoldingRangeProvider like this extension does, as it supports middle expressions. But that is a pretty involved effort.

If you want to play around with this yourself, you can follow the contributing guide to download the git repo and run the extension in the debugger.

[joecrop]

Another potential solution is to install this extension and configure it to support else folding.

[eng-tp]

Hi @joecrop,

Thanks for your comments. I will see if I can find the time to experiment with the git repo.

In any case, to me a quick & dirty fix would be to remove the else/elsif from both the begin and end patterns, leaving just the ifdef/ifndef as begin, and endif as end - it would fold everything inside the same ifdef/endif, but it would be much better than the current behavior.

If I can try this out and get it to work, I'll let you know.

Cheers,
Tiago