Windows 10 native (spac)emacs install can't call cygwin binary (ledger) with proper path passed

Question

I'd like to use Windows (10) native Emacs (spacemacs) and ledger (both installed via Chocolatey). The finance layer from spacemacs provides integration for it, however when I tried to run a simple register report it gave me the following error:

Report: reg
Command: "ledger" -f "c:/Users/USERNAME/Dropbox/Priv/2018.ledger" reg
=================================================================================================================================================

Error: Cannot read journal file "/cygdrive/c/Users/USERNAME/Dropbox/Priv/c:/Users/USERNAME/Dropbox/Priv/2018.ledger"

I assume this is because the chocolatey installed package is cygwin based.

Do You have an idea how to get rid of this problem?

Answer 1

The path you passed (c:/Users/USERNAME/Dropbox/Priv/2018.ledger) is not a valid cygwin file-path, it is a MS-windows file-path:

It will look like a relative file-path to cygwin, so will be appended to the present working directory. I assume that /cygdrive/c/Users/USERNAME/Dropbox/Priv/ | c:/Users/USERNAME/Dropbox/Priv is your present working directory.

If ledger is a cygwin application, then pass it a cygwin file-path. /cygdrive/c/Users/USERNAME/Dropbox/Priv/2018.ledger

After testing the above, if you need to pass MS-windows paths then write a wrapper, possably in bash, to use cygpath to translate the path from MS-windows to cygwin.

Answer 2

I don't use ledger-mode but I am pretty sure that the following advice-add will help you. The code is only partially tested (up to make-process in ledger-flymake). Please test whether it is working for you.

It converts the drive specification \`[[:alpha:]]: in buffer-file-name of your ledger buffer selective for function ledger-flymake into /cygdrive/\1 where \1 stands for the drive letter.

(defun run-with-cygwin-file-path (fun &rest args)
  "Let-transform `buffer-file-name' to cygwin-format and run FUN with ARGS."
  (let ((file-name (buffer-file-name)))
    (if (string-match "\\`\\([[:alpha:]]\\):" file-name)
    (let ((buffer-file-name (replace-match "/cygdrive/\\1" nil nil file-name)))
      (apply fun args))
      (apply fun args))))

(advice-add 'ledger-flymake :around #'run-with-cygwin-file-path)