git-gui: call do_quit before destroying the main window

If the toplevel window for the window being destroyed is the main window
(aka "."), then simply destroying it means the cleanup tasks are not
executed (like saving the commit message buffer, saving window state,
etc.)

All this is handled by do_quit.  Call it instead of directly
destroying the main window. For other toplevel windows, the old
behavior remains.

Signed-off-by: Pratyush Yadav <[email protected]>
Signed-off-by: Junio C Hamano <[email protected]>

Author: prati0100

git-gui.sh

@@ -3006,8 +3006,23 @@ unset doc_path doc_url
 wm protocol . WM_DELETE_WINDOW do_quit
 bind all <$M1B-Key-q> do_quit
 bind all <$M1B-Key-Q> do_quit
-bind all <$M1B-Key-w> {destroy [winfo toplevel %W]}
-bind all <$M1B-Key-W> {destroy [winfo toplevel %W]}
+
+set m1b_w_script {
+	set toplvl_win [winfo toplevel %W]
+
+	# If we are destroying the main window, we should call do_quit to take
+	# care of cleanup before exiting the program.
+	if {$toplvl_win eq "."} {
+		do_quit
+	} else {
+		destroy $toplvl_win
+	}
+}
+
+bind all <$M1B-Key-w> $m1b_w_script
+bind all <$M1B-Key-W> $m1b_w_script
+
+unset m1b_w_script
 
 set subcommand_args {}
 proc usage {} {