[Emacs-diffs] Changes to emacs/src/indent.c,v

[Chong Yidong]

CVSROOT:        /cvsroot/emacs
Module name:    emacs
Changes by:     Chong Yidong <cyd>      06/09/26 19:25:35

Index: indent.c
===================================================================
RCS file: /cvsroot/emacs/emacs/src/indent.c,v
retrieving revision 1.185
retrieving revision 1.186
diff -u -b -r1.185 -r1.186
--- indent.c    15 Sep 2006 01:53:18 -0000      1.185
+++ indent.c    26 Sep 2006 19:25:35 -0000      1.186
@@ -2074,7 +2074,7 @@
     {
       int it_start;
       int oselective;
-      int start_on_image_or_stretch_or_string_p;
+      int it_overshoot_expected_p;
 
       SET_TEXT_POS (pt, PT, PT_BYTE);
       start_display (&it, w, pt);
@@ -2086,9 +2086,26 @@
         while the end position is really at some X > 0, the same X that
         PT had.  */
       it_start = IT_CHARPOS (it);
-      start_on_image_or_stretch_or_string_p = (it.method == GET_FROM_IMAGE
-                                              || it.method == GET_FROM_STRETCH
-                                              || it.method == GET_FROM_STRING);
+
+      /* We expect the call to move_it_to, further down, to overshoot
+        if the starting point is on an image, stretch glyph, or Lisp
+        string.  We won't need to backtrack in this situation, except
+        for one corner case: when the Lisp string contains a
+        newline.  */
+      if (it.method == GET_FROM_STRING)
+       {
+         const char *s = SDATA (it.string);
+         const char *e = s + SBYTES (it.string);
+
+         while (s < e && *s != '\n')
+           ++s;
+
+         it_overshoot_expected_p = (s == e);
+       }
+      else
+       it_overshoot_expected_p = (it.method == GET_FROM_IMAGE
+                                  || it.method == GET_FROM_STRETCH);
+
       reseat_at_previous_visible_line_start (&it);
       it.current_x = it.hpos = 0;
       /* Temporarily disable selective display so we don't move too far */
@@ -2099,10 +2116,9 @@
 
       /* Move back if we got too far.  This may happen if
         truncate-lines is on and PT is beyond right margin.
-        It may also happen if it_start is on an image, stretch
-        glyph, or string -- in that case, don't go back.  */
+        Don't go back if the overshoot is expected (see above).  */
       if (IT_CHARPOS (it) > it_start && XINT (lines) > 0
-         && !start_on_image_or_stretch_or_string_p)
+         && !it_overshoot_expected_p)
        move_it_by_lines (&it, -1, 0);
 
       it.vpos = 0;