(next_overlay_string): Fix assert.

(push_it, pop_it): Handle composition and stretch specific values.
Only handle it->slice in image (for now).
(back_to_previous_visible_line_start): Continue search if newline is
part of a compisition.  Simplify.
(reseat_1): Set it->object to buffer.
(set_iterator_to_next): Set it->object to string or buffer, when
setting it->method to GET_FROM_STRING or GET_FROM_BUFFER.
(next_element_from_composition): Set it->object to buffer if not
from string.
(set_cursor_from_row): Only save start of string if not already
done to handle multiple strings in a row.

1 files changed, 92 insertions, 48 deletions

diff --git a/src/xdisp.c b/src/xdisp.c
index 4c1068119ea..f6518e08599 100644
--- a/src/xdisp.c
+++ b/src/xdisp.c
@@ -4556,6 +4556,7 @@ next_overlay_string (it)
 
       pop_it (it);
       xassert (it->sp > 0
+               || it->method == GET_FROM_COMPOSITION
                || (NILP (it->string)
                    && it->method == GET_FROM_BUFFER
                    && it->stop_charpos >= BEGV
@@ -4903,18 +4904,31 @@ push_it (it)
   p->stop_charpos = it->stop_charpos;
   xassert (it->face_id >= 0);
   p->face_id = it->face_id;
-  p->image_id = it->image_id;
+  p->string = it->string;
   p->method = it->method;
-  if (it->method == GET_FROM_IMAGE)
-    p->string = it->object;
-  else
-    p->string = it->string;
+  switch (p->method)
+    {
+    case GET_FROM_IMAGE:
+      p->u.image.object = it->object;
+      p->u.image.image_id = it->image_id;
+      p->u.image.slice = it->slice;
+      break;
+    case GET_FROM_COMPOSITION:
+      p->u.comp.object = it->object;
+      p->u.comp.c = it->c;
+      p->u.comp.len = it->len;
+      p->u.comp.cmp_id = it->cmp_id;
+      p->u.comp.cmp_len = it->cmp_len;
+      break;
+    case GET_FROM_STRETCH:
+      p->u.stretch.object = it->object;
+      break;
+    }
   p->pos = it->current;
   p->end_charpos = it->end_charpos;
   p->string_nchars = it->string_nchars;
   p->area = it->area;
   p->multibyte_p = it->multibyte_p;
-  p->slice = it->slice;
   p->space_width = it->space_width;
   p->font_height = it->font_height;
   p->voffset = it->voffset;
@@ -4941,23 +4955,33 @@ pop_it (it)
   p = it->stack + it->sp;
   it->stop_charpos = p->stop_charpos;
   it->face_id = p->face_id;
-  it->method = p->method;
-  it->image_id = p->image_id;
   it->current = p->pos;
-  if (it->method == GET_FROM_IMAGE)
-    {
-      it->object = it->string;
-      it->string = Qnil;
-    }
-  else
-    it->string = p->string;
+  it->string = p->string;
   if (NILP (it->string))
     SET_TEXT_POS (it->current.string_pos, -1, -1);
+  it->method = p->method;
+  switch (it->method)
+    {
+    case GET_FROM_IMAGE:
+      it->image_id = p->u.image.image_id;
+      it->object = p->u.image.object;
+      it->slice = p->u.image.slice;
+      break;
+    case GET_FROM_COMPOSITION:
+      it->object = p->u.comp.object;
+      it->c = p->u.comp.c;
+      it->len = p->u.comp.len;
+      it->cmp_id = p->u.comp.cmp_id;
+      it->cmp_len = p->u.comp.cmp_len;
+      break;
+    case GET_FROM_STRETCH:
+      it->object = p->u.comp.object;
+      break;
+    }
   it->end_charpos = p->end_charpos;
   it->string_nchars = p->string_nchars;
   it->area = p->area;
   it->multibyte_p = p->multibyte_p;
-  it->slice = p->slice;
   it->space_width = p->space_width;
   it->font_height = p->font_height;
   it->voffset = p->voffset;
@@ -5108,35 +5132,43 @@ back_to_previous_visible_line_start (it)
           continue;
       }
 
-      /* If newline has a display property that replaces the newline with something
-         else (image or text), find start of overlay or interval and continue search
-         from that point.  */
-      if (IT_CHARPOS (*it) > BEGV)
-        {
-          struct it it2 = *it;
-          int pos;
-          int beg, end;
-          Lisp_Object val, overlay;
-
-          pos = --IT_CHARPOS (it2);
-          --IT_BYTEPOS (it2);
-          it2.sp = 0;
-          if (handle_display_prop (&it2) == HANDLED_RETURN
-              && !NILP (val = get_char_property_and_overlay
-                        (make_number (pos), Qdisplay, Qnil, &overlay))
-              && (OVERLAYP (overlay)
-                  ? (beg = OVERLAY_POSITION (OVERLAY_START (overlay)))
-                  : get_property_and_range (pos, Qdisplay, &val, &beg, &end, Qnil)))
-            {
-              if (beg < BEGV)
-                beg = BEGV;
-              IT_CHARPOS (*it) = beg;
-              IT_BYTEPOS (*it) = buf_charpos_to_bytepos (current_buffer, beg);
-              continue;
-            }
-        }
+      if (IT_CHARPOS (*it) <= BEGV)
+        break;
 
-      break;
+      {
+        struct it it2;
+        int pos;
+        int beg, end;
+        Lisp_Object val, overlay;
+
+        /* If newline is part of a composition, continue from start of composition */
+        if (find_composition (IT_CHARPOS (*it), -1, &beg, &end, &val, Qnil)
+            && beg < IT_CHARPOS (*it))
+          goto replaced;
+
+        /* If newline is replaced by a display property, find start of overlay
+           or interval and continue search from that point.  */
+        it2 = *it;
+        pos = --IT_CHARPOS (it2);
+        --IT_BYTEPOS (it2);
+        it2.sp = 0;
+        if (handle_display_prop (&it2) == HANDLED_RETURN
+            && !NILP (val = get_char_property_and_overlay
+                      (make_number (pos), Qdisplay, Qnil, &overlay))
+            && (OVERLAYP (overlay)
+                ? (beg = OVERLAY_POSITION (OVERLAY_START (overlay)))
+                : get_property_and_range (pos, Qdisplay, &val, &beg, &end, Qnil)))
+          goto replaced;
+
+        /* Newline is not replaced by anything -- so we are done.  */
+        break;
+
+      replaced:
+        if (beg < BEGV)
+          beg = BEGV;
+        IT_CHARPOS (*it) = beg;
+        IT_BYTEPOS (*it) = buf_charpos_to_bytepos (current_buffer, beg);
+      }
     }
 
   it->continuation_lines_width = 0;
@@ -5272,6 +5304,7 @@ reseat_1 (it, pos, set_stop_p)
   IT_STRING_BYTEPOS (*it) = -1;
   it->string = Qnil;
   it->method = GET_FROM_BUFFER;
+  it->object = it->w->buffer;
   it->area = TEXT_AREA;
   it->multibyte_p = !NILP (current_buffer->enable_multibyte_characters);
   it->sp = 0;
@@ -5759,6 +5792,7 @@ set_iterator_to_next (it, reseat_p)
           IT_STRING_BYTEPOS (*it) += it->len;
           IT_STRING_CHARPOS (*it) += it->cmp_len;
           it->method = GET_FROM_STRING;
+          it->object = it->string;
           goto consider_string_end;
         }
       else
@@ -5766,6 +5800,7 @@ set_iterator_to_next (it, reseat_p)
           IT_BYTEPOS (*it) += it->len;
           IT_CHARPOS (*it) += it->cmp_len;
           it->method = GET_FROM_BUFFER;
+          it->object = it->w->buffer;
         }
       break;
 
@@ -5795,7 +5830,10 @@ set_iterator_to_next (it, reseat_p)
           else if (STRINGP (it->string))
             it->method = GET_FROM_STRING;
           else
-            it->method = GET_FROM_BUFFER;
+            {
+              it->method = GET_FROM_BUFFER;
+              it->object = it->w->buffer;
+            }
 
           it->dpvec = NULL;
           it->current.dpvec_index = -1;
@@ -6080,6 +6118,7 @@ next_element_from_ellipsis (it)
          setting face_before_selective_p.  */
       it->saved_face_id = it->face_id;
       it->method = GET_FROM_BUFFER;
+      it->object = it->w->buffer;
       reseat_at_next_visible_line_start (it, 1);
       it->face_before_selective_p = 1;
     }
@@ -6268,6 +6307,8 @@ next_element_from_composition (it)
                   : it->current.pos);
   if (STRINGP (it->string))
     it->object = it->string;
+  else
+    it->object = it->w->buffer;
   return 1;
 }
 
@@ -11709,9 +11750,12 @@ set_cursor_from_row (w, row, matrix, delta, delta_bytes, dy, dvpos)
         }
       else
         {
-          string_before_pos = last_pos;
-          string_start = glyph;
-          string_start_x = x;
+          if (string_start == NULL)
+            {
+              string_before_pos = last_pos;
+              string_start = glyph;
+              string_start_x = x;
+            }
           /* Skip all glyphs from string.  */
           do
             {