vim-patch:8.2.4609: :unhide does not check for failing to close a window (#25317)

Problem:    :unhide does not check for failing to close a window.
Solution:   When closing a window fails continue with the next one.  Do not
            try closing the autocmd window. (closes vim/vim#9984)

6f2465d336

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

src/nvim/autocmd.c

@@ -1341,7 +1341,6 @@ void aucmd_restbuf(aco_save_T *aco)
   if (aco->use_aucmd_win_idx >= 0) {
     win_T *awp = aucmd_win[aco->use_aucmd_win_idx].auc_win;
 
-    curbuf->b_nwindows--;
     // Find "awp", it can't be closed, but it may be in another tab page.
     // Do not trigger autocommands here.
     block_autocmds();
@@ -1357,7 +1356,7 @@ void aucmd_restbuf(aco_save_T *aco)
       }
     }
 win_found:
-    ;
+    curbuf->b_nwindows--;
     const bool save_stop_insert_mode = stop_insert_mode;
     // May need to stop Insert mode if we were in a prompt buffer.
     leaving_window(curwin);

src/nvim/buffer.c

@@ -3625,12 +3625,15 @@ void ex_buffer_all(exarg_T *eap)
                : wp->w_width != Columns)
            || (had_tab > 0 && wp != firstwin))
           && !ONE_WINDOW
-          && !(wp->w_closing
-               || wp->w_buffer->b_locked > 0)) {
-        win_close(wp, false, false);
-        wpnext = firstwin;              // just in case an autocommand does
-                                        // something strange with windows
-        tpnext = first_tabpage;         // start all over...
+          && !(wp->w_closing || wp->w_buffer->b_locked > 0)
+          && !is_aucmd_win(wp)) {
+        if (win_close(wp, false, false) == FAIL) {
+          break;
+        }
+        // Just in case an autocommand does something strange with
+        // windows: start all over...
+        wpnext = firstwin;
+        tpnext = first_tabpage;
         open_wins = 0;
       } else {
         open_wins++;
@@ -3650,7 +3653,7 @@ void ex_buffer_all(exarg_T *eap)
   //
   // Don't execute Win/Buf Enter/Leave autocommands here.
   autocmd_no_enter++;
-  win_enter(lastwin, false);
+  win_enter(lastwin_nofloating(), false);
   autocmd_no_leave++;
   for (buf = firstbuf; buf != NULL && open_wins < count; buf = buf->b_next) {
     // Check if this buffer needs a window
@@ -3742,7 +3745,7 @@ void ex_buffer_all(exarg_T *eap)
   // Close superfluous windows.
   for (wp = lastwin; open_wins > count;) {
     r = (buf_hide(wp->w_buffer) || !bufIsChanged(wp->w_buffer)
-         || autowrite(wp->w_buffer, false) == OK);
+         || autowrite(wp->w_buffer, false) == OK) && !is_aucmd_win(wp);
     if (!win_valid(wp)) {
       // BufWrite Autocommands made the window invalid, start over
       wp = lastwin;

test/old/testdir/test_autocmd.vim

@@ -4,6 +4,7 @@ source shared.vim
 source check.vim
 source term_util.vim
 source screendump.vim
+source vim9.vim
 source load.vim
 
 func s:cleanup_buffers() abort
@@ -3432,6 +3433,20 @@ func Test_autocmd_vimgrep()
   augroup END
 endfunc
 
+func Test_closing_autocmd_window()
+  let lines =<< trim END
+      edit Xa.txt
+      tabnew Xb.txt
+      autocmd BufEnter Xa.txt unhide 1
+      doautoall BufEnter
+  END
+  call CheckScriptFailure(lines, 'E814:')
+  au! BufEnter
+  only!
+  bwipe Xa.txt
+  bwipe Xb.txt
+endfunc
+
 func Test_bufwipeout_changes_window()
   " This should not crash, but we don't have any expectations about what
   " happens, changing window in BufWipeout has unpredictable results.