bug#11408: 24.1.50; [PATCH] Don't inherit faces when untabifying the man page

[Wolfgang Jenkner]

Look a the emacs(1) man page

M-x m a n <return> e m a c s <return>

You may (or may not, depending on how your man program outputs tab
characters) observe that the underlining of some words protrudes to the
following white space.  E.g., I see occurrences of "Emacs  windows" or
"Emacs.   Help" where the (multiple) space characters are underlined.

GNU Emacs 24.1.50.1 (amd64-unknown-freebsd9.0, GTK+ Version 2.24.6)
 of 2012-05-02 on iznogoud.viz


2012-05-04  Wolfgang Jenkner  <wjenkner@inode.at>

        * man.el (Man-unindent): Use text-property-default-nonsticky to
        prevent untabify from inheriting `face' text properties.
        In particular, underlined white space didn't look so hot.


=== modified file 'lisp/man.el'
--- lisp/man.el 2012-04-28 21:59:08 +0000
+++ lisp/man.el 2012-05-04 16:18:33 +0000
@@ -1475,7 +1475,12 @@
            (nindent 0))
        (narrow-to-region (car page) (car (cdr page)))
        (if Man-uses-untabify-flag
-           (untabify (point-min) (point-max)))
+           (let ((text-property-default-nonsticky
+                  ;; The space characters `untabify' (or rather `indent-to')
+                  ;; inserts inherit sticky text properties, which is
+                  ;; unnecessary and looks exceedingly ugly with `underline'.
+                  (cons '(face . t) text-property-default-nonsticky)))
+             (untabify (point-min) (point-max))))
        (if (catch 'unindent
              (goto-char (point-min))
              (if (not (re-search-forward Man-first-heading-regexp nil t))