vim-patch:8.2.0987: Vim9: cannot assign to [var; var]

Problem:    Vim9: cannot assign to [var; var].
Solution:   Assign rest of items to a list.

https://github.com/vim/vim/commit/9af78769eeae0318e07aa8b6af4d6e2244481ca7

Co-authored-by: Bram Moolenaar <Bram@vim.org>

2 files changed, 12 insertions, 9 deletions

diff --git a/src/nvim/eval.c b/src/nvim/eval.c
index 1dfa853fd3..18fadaa157 100644
--- a/src/nvim/eval.c
+++ b/src/nvim/eval.c
@@ -3683,9 +3683,6 @@ static int eval_index(char **arg, typval_T *rettv, evalarg_T *const evalarg, boo
         n1 = (int)len;
       }
       if (range) {
-        list_T *l;
-        listitem_T *item;
-
         if (n2 < 0) {
           n2 = (int)len + n2;
         } else if (n2 >= len) {
@@ -3694,12 +3691,7 @@ static int eval_index(char **arg, typval_T *rettv, evalarg_T *const evalarg, boo
         if (!empty2 && (n2 < 0 || n2 + 1 < n1)) {
           n2 = -1;
         }
-        l = tv_list_alloc(n2 - n1 + 1);
-        item = tv_list_find(rettv->vval.v_list, n1);
-        while (n1++ <= n2) {
-          tv_list_append_tv(l, TV_LIST_ITEM_TV(item));
-          item = TV_LIST_ITEM_NEXT(rettv->vval.v_list, item);
-        }
+        list_T *l = tv_list_slice(rettv->vval.v_list, n1, n2);
         tv_clear(rettv);
         tv_list_set_ret(rettv, l);
       } else {
diff --git a/src/nvim/eval/typval.c b/src/nvim/eval/typval.c
index cf355a22fa..297adf7f9c 100644
--- a/src/nvim/eval/typval.c
+++ b/src/nvim/eval/typval.c
@@ -765,6 +765,17 @@ int tv_list_concat(list_T *const l1, list_T *const l2, typval_T *const tv)
   return OK;
 }
 
+list_T *tv_list_slice(list_T *ol, int n1, int n2)
+{
+  list_T *l = tv_list_alloc(n2 - n1 + 1);
+  listitem_T *item = tv_list_find(ol, n1);
+  for (; n1 <= n2; n1++) {
+    tv_list_append_tv(l, TV_LIST_ITEM_TV(item));
+    item = TV_LIST_ITEM_NEXT(rettv->vval.v_list, item);
+  }
+  return l;
+}
+
 typedef struct {
   char *s;
   char *tofree;