1 files changed, 39 insertions, 8 deletions

diff --git a/src/nvim/change.c b/src/nvim/change.c
index ba80e71ae6..51afb40b40 100644
--- a/src/nvim/change.c
+++ b/src/nvim/change.c
@@ -17,6 +17,7 @@
 #include "nvim/indent.h"
 #include "nvim/indent_c.h"
 #include "nvim/mark.h"
+#include "nvim/extmark.h"
 #include "nvim/memline.h"
 #include "nvim/misc1.h"
 #include "nvim/move.h"
@@ -358,6 +359,19 @@ void changed_bytes(linenr_T lnum, colnr_T col)
   }
 }
 
+/// insert/delete bytes at column
+///
+/// Like changed_bytes() but also adjust extmark for "new" bytes.
+/// When "new" is negative text was deleted.
+static void inserted_bytes(linenr_T lnum, colnr_T col, int old, int new)
+{
+  if (curbuf_splice_pending == 0) {
+    extmark_splice(curbuf, (int)lnum-1, col, 0, old, 0, new, kExtmarkUndo);
+  }
+
+  changed_bytes(lnum, col);
+}
+
 /// Appended "count" lines below line "lnum" in the current buffer.
 /// Must be called AFTER the change and after mark_adjust().
 /// Takes care of marking the buffer to be redrawn and sets the changed flag.
@@ -372,7 +386,10 @@ void appended_lines_mark(linenr_T lnum, long count)
   // Skip mark_adjust when adding a line after the last one, there can't
   // be marks there. But it's still needed in diff mode.
   if (lnum + count < curbuf->b_ml.ml_line_count || curwin->w_p_diff) {
-    mark_adjust(lnum + 1, (linenr_T)MAXLNUM, count, 0L, false);
+    mark_adjust(lnum + 1, (linenr_T)MAXLNUM, count, 0L, kExtmarkUndo);
+  } else {
+    extmark_adjust(curbuf, lnum + 1, (linenr_T)MAXLNUM, count, 0L,
+                   kExtmarkUndo);
   }
   changed_lines(lnum + 1, 0, lnum + 1, count, true);
 }
@@ -390,7 +407,8 @@ void deleted_lines(linenr_T lnum, long count)
 /// be triggered to display the cursor.
 void deleted_lines_mark(linenr_T lnum, long count)
 {
-  mark_adjust(lnum, (linenr_T)(lnum + count - 1), (long)MAXLNUM, -count, false);
+  mark_adjust(lnum, (linenr_T)(lnum + count - 1), (long)MAXLNUM, -count,
+              kExtmarkUndo);
   changed_lines(lnum, 0, lnum + count, -count, true);
 }
 
@@ -628,7 +646,7 @@ void ins_char_bytes(char_u *buf, size_t charlen)
   ml_replace(lnum, newp, false);
 
   // mark the buffer as changed and prepare for displaying
-  changed_bytes(lnum, (colnr_T)col);
+  inserted_bytes(lnum, (colnr_T)col, (int)oldlen, (int)newlen);
 
   // If we're in Insert or Replace mode and 'showmatch' is set, then briefly
   // show the match for right parens and braces.
@@ -674,7 +692,7 @@ void ins_str(char_u *s)
   assert(bytes >= 0);
   memmove(newp + col + newlen, oldp + col, (size_t)bytes);
   ml_replace(lnum, newp, false);
-  changed_bytes(lnum, col);
+  inserted_bytes(lnum, col, 0, newlen);
   curwin->w_cursor.col += newlen;
 }
 
@@ -737,7 +755,7 @@ int del_bytes(colnr_T count, bool fixpos_arg, bool use_delcombine)
   }
   // If "count" is negative the caller must be doing something wrong.
   if (count < 1) {
-    IEMSGN("E950: Invalid count for del_bytes(): %ld", count);
+    IEMSGN("E292: Invalid count for del_bytes(): %ld", count);
     return FAIL;
   }
 
@@ -795,7 +813,7 @@ int del_bytes(colnr_T count, bool fixpos_arg, bool use_delcombine)
   }
 
   // mark the buffer as changed and prepare for displaying
-  changed_bytes(lnum, curwin->w_cursor.col);
+  inserted_bytes(lnum, col, count, 0);
 
   return OK;
 }
@@ -951,6 +969,9 @@ int open_line(
   bool did_append;                // appended a new line
   int saved_pi = curbuf->b_p_pi;  // copy of preserveindent setting
 
+  linenr_T lnum = curwin->w_cursor.lnum;
+  colnr_T mincol = curwin->w_cursor.col + 1;
+
   // make a copy of the current line so we can mess with it
   char_u *saved_line = vim_strsave(get_cursor_line_ptr());
 
@@ -1560,6 +1581,7 @@ int open_line(
     end_comment_pending = NUL;  // turns out there was no leader
   }
 
+  curbuf_splice_pending++;
   old_cursor = curwin->w_cursor;
   if (dir == BACKWARD) {
     curwin->w_cursor.lnum--;
@@ -1574,7 +1596,8 @@ int open_line(
     // be marks there. But still needed in diff mode.
     if (curwin->w_cursor.lnum + 1 < curbuf->b_ml.ml_line_count
         || curwin->w_p_diff) {
-      mark_adjust(curwin->w_cursor.lnum + 1, (linenr_T)MAXLNUM, 1L, 0L, false);
+      mark_adjust(curwin->w_cursor.lnum + 1, (linenr_T)MAXLNUM, 1L, 0L,
+                  kExtmarkUndo);
     }
     did_append = true;
   } else {
@@ -1614,7 +1637,7 @@ int open_line(
       // it.  It gets restored at the function end.
       curbuf->b_p_pi = true;
     } else {
-      (void)set_indent(newindent, SIN_INSERT);
+      (void)set_indent(newindent, SIN_INSERT|SIN_NOMARK);
     }
     less_cols -= curwin->w_cursor.col;
 
@@ -1665,6 +1688,11 @@ int open_line(
                           curwin->w_cursor.col + less_cols_off,
                           1L, (long)-less_cols, 0);
         }
+        // Always move extmarks - Here we move only the line where the
+        // cursor is, the previous mark_adjust takes care of the lines after
+        int cols_added = mincol-1+less_cols_off-less_cols;
+        extmark_splice(curbuf, (int)lnum-1, mincol-1, 0, less_cols_off,
+                       1, cols_added, kExtmarkUndo);
       } else {
         changed_bytes(curwin->w_cursor.lnum, curwin->w_cursor.col);
       }
@@ -1676,7 +1704,10 @@ int open_line(
   }
   if (did_append) {
     changed_lines(curwin->w_cursor.lnum, 0, curwin->w_cursor.lnum, 1L, true);
+    extmark_splice(curbuf, (int)curwin->w_cursor.lnum-1,
+                   0, 0, 0, 1, 0, kExtmarkUndo);
   }
+  curbuf_splice_pending--;
 
   curwin->w_cursor.col = newcol;
   curwin->w_cursor.coladd = 0;