vim-patch:8.2.4203: entering a character with CTRL-V may include modifiers

Problem:    Entering a character with CTRL-V may include modifiers.
Solution:   Reset "mod_mask" when entering a character with digits after
            CTRL-V. (closes vim/vim#9610)
https://github.com/vim/vim/commit/502d8ae3e8ed8b6f8dd2ff175f154f9aa87228ef

Commenting out test_override() as before.

Commenting out part of CheckNotFeature() because Vim patch 8.2.0427
cannot be ported without breaking a lot of oldtests that check for
removed features.

1 files changed, 8 insertions, 2 deletions

diff --git a/src/nvim/edit.c b/src/nvim/edit.c
index a9c606ec13..f3226d4f6c 100644
--- a/src/nvim/edit.c
+++ b/src/nvim/edit.c
@@ -5631,8 +5631,12 @@ int get_literal(void)
   i = 0;
   for (;;) {
     nc = plain_vgetc();
-    if (!(State & CMDLINE)
-        && MB_BYTE2LEN_CHECK(nc) == 1) {
+    if ((mod_mask & ~MOD_MASK_SHIFT) != 0) {
+      // A character with non-Shift modifiers should not be a valid
+      // character for i_CTRL-V_digit.
+      break;
+    }
+    if (!(State & CMDLINE) && MB_BYTE2LEN_CHECK(nc) == 1) {
       add_to_showcmd(nc);
     }
     if (nc == 'x' || nc == 'X') {
@@ -5698,6 +5702,8 @@ int get_literal(void)
   --no_mapping;
   if (nc) {
     vungetc(nc);
+    // A character typed with i_CTRL-V_digit cannot have modifiers.
+    mod_mask = 0;
   }
   got_int = false;          // CTRL-C typed after CTRL-V is not an interrupt
   return cc;