Switch between source and header in C++

[shahamran]

Is there a way to have Helix send clangd's textDocument/switchSourceHeader request?

Reference: https://clangd.llvm.org/extensions#switch-between-sourceheader

[the-mikedavis]

We don't support language-server-specific extensions to the protocol. This should be covered by a plugin once the plugin system exists

[shahamran]

I see, makes sense.

Can you please explain what's the :lsp-workspace-command command?
Is it used to send a standard LSP request?

Thanks!

[the-mikedavis]

That is a part of the spec, see https://microsoft.github.io/language-server-protocol/specifications/lsp/3.17/specification/#workspace_executeCommand

[3541]

To close the loop, this is now possible via the Steel PR: #8675 (comment).

[objectiveryan]

I really needed this feature, so I found a workaround.

With #4709 (which has already been merged into master but isn't yet in an official release) and a helper shell script I called altname in my PATH, I use this key binding:

# Go to "other" file (header <--> source)
g = { o = "@\"%P|altfile<ret>gf<C-o>uu<C-i>" }

The altfile shell script:

#!/bin/bash

read f
f="$(basename "$f")"

if [[ $f == *.h ]]; then
  echo "${f%.h}.cc"
elif [[ $f == *.cc ]]; then
  echo "${f%.cc}.h"
else
  echo "$f"
fi

It doesn't handle non-.h/.cc files well, but it seems to work reliably when used correctly.

[pierrelgol]

@objectiveryan Yes as mentionned in my first response, you just have to use bear to generate the compile_commands.json, this is not a helix issue, it's a clangd issue, it needs a compile_commands.json, to index where each tokens are, which in turns provide the goto feature.

[objectiveryan]

@pierrelgol I have a compile_commands.json, and I can jump to declarations and definitions, but I haven’t found a way to easily jump back and forth between a header and its source file. Is there a way?

[pierrelgol]

you can do gd to go from a header file to the declaration of something.

[objectiveryan]

That's not the problem here. As mentioned above, I can already jump to declarations and definitions.

I'm talking about just jumping to the other file, for example when the declaration or definition doesn't exist yet, like when I just declared a function in the header and now I need to implement it (or vice versa). Or when I just modified the signature of a function, and now clangd won't jump to the implementation anymore because the header and source files disagree, and I need to go fix it.

This a common-enough need that clangd reluctantly extends the LSP protocol for it. Helix will support that with plugins, but until that's ready, the hacky workaround I posted above has really helped me and maybe it can help others too.

[pierrelgol]

Do you use tabs ? I usually use the file picker to switch when something doesn't exist yet. But yeah instead of making their tool better I guess they prefer to extend the protocol and defer the wok on the editors.