vim-patch:9.0.1354: "gr CTRL-G" stays in virtual replace mode

Problem:    "gr CTRL-G" stays in virtual replace mode. (Pierre Ganty)
Solution:   Prepend CTRL-V before control characters. (closes vim/vim#12045)

d6a4ea3aa0

Cherry-pick Test_edit_gr_special() from patch 9.0.1347.

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

src/nvim/edit.c

@@ -3444,6 +3444,10 @@ static void ins_ctrl_g(void)
     dont_sync_undo = kNone;
     break;
 
+  case ESC:
+    // Esc after CTRL-G cancels it.
+    break;
+
   // Unknown CTRL-G command, reserved for future expansion.
   default:
     vim_beep(BO_CTRLG);

src/nvim/normal.c

@@ -4720,6 +4720,11 @@ static void nv_vreplace(cmdarg_T *cap)
     if (cap->extra_char == Ctrl_V) {          // get another character
       cap->extra_char = get_literal(false);
     }
+    if (cap->extra_char < ' ') {
+      // Prefix a control character with CTRL-V to avoid it being used as
+      // a command.
+      stuffcharReadbuff(Ctrl_V);
+    }
     stuffcharReadbuff(cap->extra_char);
     stuffcharReadbuff(ESC);
     if (virtual_active()) {

src/nvim/testdir/test_edit.vim

@@ -2080,6 +2080,20 @@ func Test_edit_CTRL_hat()
   bwipe!
 endfunc
 
+" Test "gr" followed by an Insert mode command does get out of Insert mode.
+func Test_edit_gr_special()
+  enew
+  call setline(1, ['abcdef', 'xxxxxx'])
+  exe "normal! gr\<C-O>lx"
+  call assert_equal("\<C-O>def", getline(1))
+
+  call setline(1, 'abcdef')
+  exe "normal! 0gr\<C-G>lx"
+  call assert_equal("\<C-G>def", getline(1))
+
+  bwipe!
+endfunc
+
 " Weird long file name was going over the end of NameBuff
 func Test_edit_overlong_file_name()
   CheckUnix