vim-patch:9.1.1868: v:register is wrong in v_: command (#36238)

Problem:  v:register is wrong in v_: command (after 9.1.1858).
Solution: Don't reset v:register for OP_COLON (zeertzjq)

related: https://github.com/vim/vim/pull/18583#issuecomment-3418030021

closes: vim/vim#18597

0124320c97

While at it, also fix using stale set_prevcount value. That only matters
when readbuf1 ends with an operator or a register, which never happens,
but it's still good to avoid using a stale value.

src/nvim/normal.c

@@ -544,6 +544,7 @@ static void normal_prepare(NormalState *s)
   }
   may_trigger_modechanged();
 
+  s->set_prevcount = false;
   // When not finishing an operator and no register name typed, reset the count.
   if (!finish_op && !s->oa.regname) {
     s->ca.opcount = 0;
@@ -964,6 +965,8 @@ static bool normal_get_command_count(NormalState *s)
 
 static void normal_finish_command(NormalState *s)
 {
+  bool did_visual_op = false;
+
   if (s->command_finished) {
     goto normal_end;
   }
@@ -983,11 +986,13 @@ static void normal_finish_command(NormalState *s)
     s->old_mapped_len = typebuf_maplen();
   }
 
-  const bool prev_VIsual_active = VIsual_active;
-
   // If an operation is pending, handle it.  But not for K_IGNORE or
   // K_MOUSEMOVE.
   if (s->ca.cmdchar != K_IGNORE && s->ca.cmdchar != K_MOUSEMOVE) {
+    did_visual_op = VIsual_active && s->oa.op_type != OP_NOP
+                    // For OP_COLON, do_pending_operator() stuffs ':' into
+                    // the read buffer, which isn't executed immediately.
+                    && s->oa.op_type != OP_COLON;
     do_pending_operator(&s->ca, s->old_col, false);
   }
 
@@ -1002,7 +1007,7 @@ normal_end:
 
   msg_nowait = false;
 
-  if (finish_op || prev_VIsual_active) {
+  if (finish_op || did_visual_op) {
     set_reg_var(get_default_register_name());
   }
 

test/old/testdir/test_registers.vim

@@ -671,7 +671,9 @@ func Test_v_register()
     exec 'normal! "' .. v:register .. 'P'
   endfunc
   nnoremap <buffer> <plug>(test) :<c-u>call s:Put()<cr>
+  xnoremap <buffer> <plug>(test) :<c-u>call s:Put()<cr>
   nmap <buffer> S <plug>(test)
+  xmap <buffer> S <plug>(test)
 
   let @z = "testz\n"
   let @" = "test@\n"
@@ -689,15 +691,41 @@ func Test_v_register()
   let s:register = ''
   call feedkeys('"zS', 'mx')
   call assert_equal('z', s:register)
+  call assert_equal('testz', getline('.'))
 
   let s:register = ''
   call feedkeys('"zSS', 'mx')
   call assert_equal('"', s:register)
+  call assert_equal('test@', getline('.'))
+
+  let s:register = ''
+  call feedkeys("\"z\<Ignore>S", 'mx')
+  call assert_equal('z', s:register)
+  call assert_equal('testz', getline('.'))
 
   let s:register = ''
   call feedkeys('"_S', 'mx')
   call assert_equal('_', s:register)
 
+  let s:register = ''
+  call feedkeys('V"zS', 'mx')
+  call assert_equal('z', s:register)
+  call assert_equal('testz', getline('.'))
+
+  let s:register = ''
+  call feedkeys('V"zSS', 'mx')
+  call assert_equal('"', s:register)
+  call assert_equal('test@', getline('.'))
+
+  let s:register = ''
+  call feedkeys("V\"z\<Ignore>S", 'mx')
+  call assert_equal('z', s:register)
+  call assert_equal('testz', getline('.'))
+
+  let s:register = ''
+  call feedkeys('V"_S', 'mx')
+  call assert_equal('_', s:register)
+
   let s:register = ''
   normal "_ddS
   call assert_equal('"', s:register)        " fails before 8.2.0929