Re: compile.el error properties: buffer as filename not working

[Stefan Monnier]

> 1. In `compilation-error-properties’,
>    `compilation-transform-file-match-alist’ is matched against a nil
>    filename, since the definition of that filename looks like (note
>    the bufferp):
>
> (let ((file-name
>              (and (consp file)
>                   (not (bufferp (car file)))
>                   (if (cdr file)
>                       (expand-file-name (car file) (cdr file))
>                     (car file)))))
>
> This seems to have been fixed using a when-let in the Emacs 28 branch 
> (unconfirmed).

> 2. `compilation-get-file-structure’ is called with the file list, but
>    this function does not expect a (buffer), and calls (e.g.)
>    file-name-absolute-p(#<buffer boo.py>), resulting in an error.

Any chance you can provide a recipe or a backtrace?
Also it might be useful to provide some context, such as which package
uses this ability to return a buffer.


        Stefan