patch 9.0.0909: error message for layout change does not match action

Problem:    Error message for layout change does not match action.
Solution:   Pass the command to where the error is given. (closes #11573)

src/ex_docmd.c

@@ -6055,7 +6055,7 @@ ex_win_close(
 	emsg(_(e_cannot_close_autocmd_or_popup_window));
 	return;
     }
-    if (window_layout_locked())
+    if (window_layout_locked(CMD_close))
 	return;
 
     need_hide = (bufIsChanged(buf) && buf->b_nwindows <= 1);
@@ -6229,7 +6229,7 @@ ex_tabclose(exarg_T *eap)
 	cmdwin_result = K_IGNORE;
     else if (first_tabpage->tp_next == NULL)
 	emsg(_(e_cannot_close_last_tab_page));
-    else if (!window_layout_locked())
+    else if (!window_layout_locked(CMD_tabclose))
     {
 	tab_number = get_tabpage_arg(eap);
 	if (eap->errmsg == NULL)
@@ -6265,7 +6265,7 @@ ex_tabonly(exarg_T *eap)
 	cmdwin_result = K_IGNORE;
     else if (first_tabpage->tp_next == NULL)
 	msg(_("Already only one tab page"));
-    else if (!window_layout_locked())
+    else if (!window_layout_locked(CMD_tabonly))
     {
 	tab_number = get_tabpage_arg(eap);
 	if (eap->errmsg == NULL)
@@ -6298,7 +6298,7 @@ ex_tabonly(exarg_T *eap)
     void
 tabpage_close(int forceit)
 {
-    if (window_layout_locked())
+    if (window_layout_locked(CMD_tabclose))
 	return;
 
     // First close all the windows but the current one.  If that worked then
@@ -6346,7 +6346,7 @@ tabpage_close_other(tabpage_T *tp, int forceit)
     static void
 ex_only(exarg_T *eap)
 {
-    if (window_layout_locked())
+    if (window_layout_locked(CMD_only))
 	return;
 # ifdef FEAT_GUI
     need_mouse_correct = TRUE;
@@ -6373,7 +6373,7 @@ ex_hide(exarg_T *eap UNUSED)
     // ":hide" or ":hide | cmd": hide current window
     if (!eap->skip)
     {
-	if (window_layout_locked())
+	if (window_layout_locked(CMD_hide))
 	    return;
 #ifdef FEAT_GUI
 	need_mouse_correct = TRUE;

src/proto/window.pro

@@ -1,5 +1,5 @@
 /* window.c */
-int window_layout_locked(void);
+int window_layout_locked(enum CMD_index cmd);
 win_T *prevwin_curwin(void);
 void do_window(int nchar, long Prenum, int xchar);
 void get_wincmd_addr_type(char_u *arg, exarg_T *eap);

src/testdir/test_autocmd.vim

@@ -756,6 +756,14 @@ func Test_BufEnter()
     bwipe!
     au! BufEnter
   endfor
+
+  new
+  new
+  autocmd BufEnter * ++once close
+  call assert_fails('close', 'E1312:')
+
+  au! BufEnter
+  only
 endfunc
 
 " Closing a window might cause an endless loop

src/version.c

@@ -695,6 +695,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    909,
 /**/
     908,
 /**/

src/window.c

@@ -111,13 +111,15 @@ window_layout_unlock(void)
 
 /*
  * When the window layout cannot be changed give an error and return TRUE.
+ * "cmd" indicates the action being performed and is used to pick the relevant
+ * error message.
  */
     int
-window_layout_locked(void)
+window_layout_locked(enum CMD_index cmd)
 {
     if (split_disallowed > 0 || close_disallowed > 0)
     {
-	if (close_disallowed == 0)
+	if (close_disallowed == 0 && cmd == CMD_tabnew)
 	    emsg(_(e_cannot_split_window_when_closing_buffer));
 	else
 	    emsg(_(e_not_allowed_to_change_window_layout_in_this_autocmd));
@@ -2573,7 +2575,7 @@ win_close(win_T *win, int free_buf)
 	emsg(_(e_cannot_close_last_window));
 	return FAIL;
     }
-    if (window_layout_locked())
+    if (window_layout_locked(CMD_close))
 	return FAIL;
 
     if (win->w_closing || (win->w_buffer != NULL
@@ -4062,7 +4064,7 @@ win_new_tabpage(int after)
 	emsg(_(e_invalid_in_cmdline_window));
 	return FAIL;
     }
-    if (window_layout_locked())
+    if (window_layout_locked(CMD_tabnew))
 	return FAIL;
 
     newtp = alloc_tabpage();