vim-patch:8.2.0274: hang with combination of feedkeys(), Ex mode and :global

Problem:    Hang with combination of feedkeys(), Ex mode and :global.
            (Yegappan Lakshmanan)
Solution:   Add the pending_exmode_active flag.
9e2bcb5d23

src/nvim/ex_docmd.c

@@ -7899,9 +7899,11 @@ void do_exedit(exarg_T *eap, win_T *old_curwin)
         need_wait_return = false;
         msg_scroll = 0;
         redraw_all_later(NOT_VALID);
+        pending_exmode_active = true;
 
         normal_enter(false, true);
 
+        pending_exmode_active = false;
         RedrawingDisabled = rd;
         no_wait_return = nwr;
         msg_scroll = ms;

src/nvim/getchar.c

@@ -2475,6 +2475,11 @@ static int vgetorpeek(bool advance)
           }
           tc = c;
 
+          // return 0 in normal_check()
+          if (pending_exmode_active) {
+            exmode_active = true;
+          }
+
           // no chars to block abbreviations for
           typebuf.tb_no_abbr_cnt = 0;
 

src/nvim/globals.h

@@ -636,6 +636,10 @@ EXTERN int motion_force INIT(=0);       // motion force for pending operator
 
 // Ex Mode (Q) state
 EXTERN bool exmode_active INIT(= false);  // true if Ex mode is active
+
+/// Flag set when normal_check() should return 0 when entering Ex mode.
+EXTERN bool pending_exmode_active INIT(= false);
+
 EXTERN bool ex_no_reprint INIT(=false);   // No need to print after z or p.
 
 // 'inccommand' command preview state

src/nvim/testdir/test_ex_mode.vim

@@ -64,6 +64,14 @@ func Test_ex_mode()
   let &encoding = encoding_save
 endfunc
 
+func Test_Ex_feedkeys()
+  " this doesn't do anything useful, just check it doesn't hang
+  new
+  call setline(1, ["foo"])
+  call feedkeys("Qg/foo/visual\<CR>", "xt")
+  bwipe!
+endfunc
+
 func Test_ex_mode_errors()
   " Not allowed to enter ex mode when text is locked
   au InsertCharPre <buffer> normal! gQ<CR>