Since --remote option hasn’t been restored by Neovim, it is actually not very straightforward to set up inverse search for PDF files when we are compiling LaTeX files with the help of Vimtex.

I spend some time figuring how to do it on both Windows and macOS and succeed. I thought it would be helpful for people looking for this issue.

First step

Although Neovim removed the --remote option, but it has a complete RPC api by which client can talk to it and control its behavior. When Neovim starts, it always start a server1. The neovim-remote project utilizes the RPC api of neovim to mimic the --remote behavior and its friends. First, we need to install this package:

pip install neovim-remote

It comes with an executable named nvr. To connect to a running Neovim instance and run some command, we can run the following command:

nvr --servername server_address -c "echo 'hello'"

--servername option specify a valid Neovim server address (i.e., the value v: servername), -c option means to run a command in the specified Neovim instance.

Second step

Since each time when Neovim starts, the server address will change, it is cumbersome to copy this address when we when to control the Neovim instance. We can write the server address to temp file and read the server address from that file when we run the nvr command.

Add the following setting to nvim config:

function! SetServerName()
  if has('win32')
    let nvim_server_file = $TEMP . "/curnvimserver.txt"
  else
    let nvim_server_file = "/tmp/curnvimserver.txt"
  endif
  let cmd = printf("echo %s > %s", v:servername, nvim_server_file)
  call system(cmd)
endfunction

augroup vimtex_common
    autocmd!
    autocmd FileType tex call SetServerName()
augroup END

When we open a LaTeX source file, the server name will be written to curnvimserver.txt so that we can later read it easily.

Third step

Now we need to set up the corresponding PDF viewer to do inverse search. The setup differs based on the system and PDF viewer.

Skim on macOS

Open Skim PDF viewer, open the Preferences menu and go to Sync page. Set the part PDF-Tex Sync support, use the following settings:

• Preset: Custom
• Command: nvr
• Arguments: --servername `cat /tmp/curnvimserver.txt` +"%line" "%file"

To start inverse search, press Shift and Command key, then click the text you want to inv-search.

Sumatra PDF on Windows

Open Sumatra PDF, go to Settings --> Options, in the bottom part, there is a section Set inverse search command-line, put the following command there:

cmd /c for /F %i in ('type C:\Users\ADMINI~1\AppData\Local\Temp\curnvimserver.txt') do nvr --servername %i -c "normal! zzzv" +"%l" "%f"

• %f: it means the tex source file path corresponding to the current pdf.
• %l: it means the line in the original tex file.

I know the above command is complicated and looks super weird, but it’s the only way that works out of the numerous other ways that I have tried. Note that cmd /c is needed, without which Sumatra PDF will complain that the inverse search command is wrong:

Can not start inverse search command. Please check the command line in the settings.

Double click somewhere in the PDF file, your cursor in nvim/nvim-qt should go to the corresponding line in the file buffer.

I have also post this setup on Vimtex repo, see this issue.

Conclusion

In this post, I give a summary on how to set up inverse search for Neovim on different platforms. After all this setup, inverse search should work out of box without any manual labor.

1. You can find the name of the server by running command :echo v:servername inside Neovim. ↩︎

Author jdhao

LastMod 2021-02-22

License CC BY-NC-ND 4.0