bug#3418: Issue with compile.el and compilation-parse-errors-filename-function

[Gary Oberbrunner]

This sounds perfect to me.

On Thu, Aug 10, 2017 at 8:50 PM, <npostavs@users.sourceforge.net> wrote:

Gary Oberbrunner <garyo@genarts.com> writes:

> If a user (such as myself) has an implementation of this function in his .emacs today, like so:
>
> (defun process-error-filename (filename)
>   ;;; do stuff with filename
>   filename)
> (setq compilation-parse-errors-filename-function 'process-error-filename)
>
> and we add a new argument that gets passed to that function, it'll throw an error. *Users* will have to add
>   &optional spec-dir
> to their implementations of it to avoid the error.

We could do something like

    (condition-case err
        (funcall compilation-parse-errors-filename-function filename spec-dir)
      (wrong-number-of-arguments
       ;; Try again with single arg for backwards compatibility.
       (funcall compilation-parse-errors-filename-function filename)))

--

Gary Oberbrunner -- CTO -- Boris FX