Fixed FileNotFoundError which occurred when running 'history --clear' and no history file existed.

Author: kmvanbrunt

CHANGELOG.md

@@ -3,6 +3,7 @@
     * Fixed bug where setting `always_show_hint=True` did not show a hint when completing `Settables`
     * Fixed bug in editor detection logic on Linux systems that do not have `which`
     * Fixed bug in table creator where column headers with tabs would result in an incorrect width calculation
+    * Fixed `FileNotFoundError` which occurred when running `history --clear` and no history file existed.
 * Enhancements
     * Added `silent_startup_script` option to `cmd2.Cmd.__init__()`. If `True`, then the startup script's
       output will be suppressed. Anything written to stderr will still display.

cmd2/cmd2.py

@@ -3989,7 +3989,10 @@ def do_history(self, args: argparse.Namespace) -> Optional[bool]:
             self.history.clear()
 
             if self.persistent_history_file:
-                os.remove(self.persistent_history_file)
+                try:
+                    os.remove(self.persistent_history_file)
+                except FileNotFoundError:
+                    pass
 
             if rl_type != RlType.NONE:
                 readline.clear_history()