vim tidy makeprg with stdin

Question

I've got this in .vim/ftplugin/html.vim:

set makeprg=%!tidy\ -q\ -i\ --show-warnings\ no

If I do make in a html file I get this error:

E499: Empty file name for '%' or '#', only works with ":p:h"

When I execute this:

:%!tidy -q -i --show-warnings no

It works beautifully. What am I doing wrong with my set makeprg?

Answer 1

I don't think makeprg was intended to be used that way. I suggest you simply define your own mapping or command

:map ,m :%!tidy -q -i --show-warnings no<CR>
:Command Make %!tidy -q -i --show-warnings no<CR>

%! replaces the contents of the buffer with the output of the following command, but when calling :make, the % is replaced with the file name for the current buffer. The error comes, because your current buffer is not editing a file, so the % replacement can't take place.