Subject: bug#18830: gnus-summary-line-format text face

From: Wolfgang Jenkner <[email-masked]>
Date: Sun, 26 Oct 2014 16:00:13 +0100

On Sat, Oct 25 2014, Zhitao Gong wrote:

>       (t
>        (propertize header-date-time-string
>                    'face 'my-date-more-than-one-week-old-face
>                    'gnus-face t)))))
>
> (setq-default
>  gnus-summary-line-format "%U%R%z %(%u&color-date;  %-30,30f  %B%s%)\n")
>                                         ^---- this is my function

A similar case was reported in the thread starting with:

http://permalink.gmane.org/gmane.emacs.gnus.general/82816

Strictly speaking, gnus-face is an undocumented text property for
internal purposes; practically speaking, however, your use case requires
using it in some way.

The thread cited above indicates two possible solutions: 

1) Rewrite your code to mimic how gnus does things now (i.e., replace
   my-date-one-day-old-face as the value of the face text property by,
   e.g., (list 'my-date-one-day-old-face 'default), etc.)
   See also gnus-face-face-function.

or

2) There's a (small, but somewhat ugly) compatibility patch in the last
message in the thread, viz.,

http://permalink.gmane.org/gmane.emacs.gnus.general/82826