vim-patch:8.1.0535: increment/decrement might get interrupted by updating folds

Problem:    Increment/decrement might get interrupted by updating folds.
Solution:   Disable fold updating for a moment. (Christian Brabandt,
            closes vim/vim#3599)
https://github.com/vim/vim/commit/6b731886ca94d66b9bdedfb7e603af44a6400399

1 files changed, 10 insertions, 0 deletions

diff --git a/src/nvim/ops.c b/src/nvim/ops.c
index c3d7742307..0be49aaad4 100644
--- a/src/nvim/ops.c
+++ b/src/nvim/ops.c
@@ -4911,12 +4911,19 @@ void op_addsub(oparg_T *oap, linenr_T Prenum1, bool g_cmd)
   ssize_t change_cnt = 0;
   linenr_T amount = Prenum1;
 
+  // do_addsub() might trigger re-evaluation of 'foldexpr' halfway, when the
+  // buffer is not completly updated yet. Postpone updating folds until before
+  // the call to changed_lines().
+  disable_fold_update++;
+
   if (!VIsual_active) {
     pos = curwin->w_cursor;
     if (u_save_cursor() == FAIL) {
+      disable_fold_update--;
       return;
     }
     change_cnt = do_addsub(oap->op_type, &pos, 0, amount);
+    disable_fold_update--;
     if (change_cnt) {
       changed_lines(pos.lnum, 0, pos.lnum + 1, 0L, true);
     }
@@ -4927,6 +4934,7 @@ void op_addsub(oparg_T *oap, linenr_T Prenum1, bool g_cmd)
 
     if (u_save((linenr_T)(oap->start.lnum - 1),
                (linenr_T)(oap->end.lnum + 1)) == FAIL) {
+      disable_fold_update--;
       return;
     }
 
@@ -4973,6 +4981,8 @@ void op_addsub(oparg_T *oap, linenr_T Prenum1, bool g_cmd)
         amount += Prenum1;
       }
     }
+
+    disable_fold_update--;
     if (change_cnt) {
       changed_lines(oap->start.lnum, 0, oap->end.lnum + 1, 0L, true);
     }