Persistent history file not saved when application is killed

[shimomut]

When killing the Cmd2 application (e.g. by closing the terminal window), persistent history file is not saved.

By using persistent_history_file argument for Cmd.init(), and hitting quit command, I can see the persistent history command is updated as expected.

Environment : Ubuntu 22 on WLS2

[shimomut]

I checked the behavior of bash and ipython. They save history persistently even when I close terminal window.

[shimomut]

As a hacky solution, I was able to use _persist_history() private method in postcmd_hook to save command history immediately after all command executions.

    def __init__(self):
            :
        self.register_postcmd_hook(self.on_command_executed)
            :


    def on_command_executed(self, data: cmd2.plugin.PostcommandData) -> cmd2.plugin.PostcommandData:
        
        # Save command history immediately
        self._persist_history()

        return data

[shimomut]

Thank you for fixing this issue. I verified the fix.