use intermediate / temporary file

[davidosomething]

for markdownlint-cli it can only fix files in place (no stdin)
so needs to copy current file to a temp file, apply fix, and then copy contents back

[davidosomething]

e.g. how null-ls creates a temporary buffer:
https://github.com/jose-elias-alvarez/null-ls.nvim/blob/main/lua/null-ls/formatting.lua

[chrisgrieser]

yes please 🙏

There are a bunch of formatters/linters with auto-fix which do not work with stdin. Of the top of my head:

• codespell
• markdownlint
• shellcheck (with the git apply workaround)

[creativenull]

There is some confusion here. formatStdin dictates how the input will be sent to the cli tool. Will it be from stdin? Or will it be handled externally (like pass in the filename/filepath)? This works as expected.

I think what you are referring to is to somehow control stdout that is passed back to the LSP client.

I think what is needed is something similar to lintIgnoreExitCode like formatIgnoreStdout if the cli tool does not support outputting the changes to stdout then just ignore them.

[creativenull]

However I don't see the LSP server like efm provide a way to channel these changes from a temp file to stdout.

I think it's the LSP client's responsibility to make sure the changes are shown if done externally just like it was done from stdout.

For vim/neovim we have :edit! to reload the buffer if the file changed outside of neovim but is kinda hacky but is the only way I know to see these changes.

[mattn]

Some linter/formatter command looks current directory, file name, file extension, or configuration files. So temporary file might not fix something.