Document new :extend face attribute in manuals.

Some stylistic corrections in src/xdisp.c and src/xfaces.c.

2 files changed, 27 insertions, 0 deletions

diff --git a/doc/emacs/mark.texi b/doc/emacs/mark.texi
index bbeb4cb039e..f012d72fc2a 100644
--- a/doc/emacs/mark.texi
+++ b/doc/emacs/mark.texi
@@ -23,6 +23,11 @@ When the mark is active, we say also that the region is active; Emacs
 indicates its extent by highlighting the text within it, using the
 @code{region} face (@pxref{Face Customization}).
 
+This is one of the few faces that has the @code{:extend t} attribute
+by default, which implies that the same face is used to highlight the
+text and space between end of line and the window border.  To
+highlight only the text you could set this attribute to @code{nil}.
+
 @cindex deactivating the mark
   After certain non-motion commands, including any command that
 changes the text in the buffer, Emacs automatically @dfn{deactivates}
diff --git a/doc/lispref/display.texi b/doc/lispref/display.texi
index 61bd4ce8830..1678d32db0a 100644
--- a/doc/lispref/display.texi
+++ b/doc/lispref/display.texi
@@ -2482,6 +2482,17 @@ faces (@pxref{Displaying Faces}).  If the face to inherit from is
 never merges @code{:inherit} attributes.  If a list of faces is used,
 attributes from faces earlier in the list override those from later
 faces.
+
+@item :extend
+Whether or not this face will be extended until the end of the window.
+The value should be @code{t} to extend until end of the window using
+this face or @code{nil} fill the space between the end of the line and
+the end of the window with the default face.  When a face is conformed
+by merging multiple other faces; only those with @code{:extend t} will
+be merged to conform a new face to extend until end of window.  By
+default only @code{region} and @code{hl-line} have this attribute set
+to @code{t}.
+
 @end table
 
 @defun font-family-list &optional frame
@@ -2842,6 +2853,11 @@ This sets the @code{:inverse-video} attribute of @var{face} to
 This swaps the foreground and background colors of face @var{face}.
 @end deffn
 
+@deffn Command set-face-extend face extend &optional frame
+This sets the @code{:extend} attribute of @var{face} to
+@var{extend}.
+@end deffn
+
   The following functions examine the attributes of a face.  They
 mostly provide compatibility with old versions of Emacs.  If you don't
 specify @var{frame}, they refer to the selected frame; @code{t} refers
@@ -2900,6 +2916,12 @@ This function returns non-@code{nil} if face @var{face} specifies
 a non-@code{nil} @code{:inverse-video} attribute.
 @end defun
 
+@defun face-extend-p face &optional frame
+This function returns non-@code{nil} if face @var{face} specifies
+a non-@code{nil} @code{:extend} attribute.
+@end defun
+
+
 @node Displaying Faces
 @subsection Displaying Faces
 @cindex displaying faces