Core - Add invoke error message customisation (#5894)

Co-authored-by: Jakub Kuczys <me@jacken.men>

docs/cog_guides/core.rst

@@ -3080,6 +3080,35 @@ This is only applied to the current server and not globally.
 **Arguments:**
     - ``[time]`` - The seconds to wait before deleting the command message. Use -1 to disable.
 
+.. _core-command-set-errormsg:
+
+""""""""""""
+set errormsg
+""""""""""""
+
+.. note:: |owner-lock|
+
+**Syntax**
+
+.. code-block:: none
+
+    [p]set errormsg [msg]
+
+**Description**
+
+Set the message that will be sent on uncaught bot errors.
+
+To include the command name in the message, use the ``{command}`` placeholder.
+
+If you omit the ``msg`` argument, the message will be reset to the default one.
+
+**Examples:**
+    - ``[p]set errormsg`` - Resets the error message back to the default: "Error in command '{command}'.". If the command invoker is one of the bot owners, the message will also include "Check your console or logs for details.".
+    - ``[p]set errormsg Oops, the command {command} has failed! Please try again later.`` - Sets the error message to a custom one.
+
+**Arguments:**
+    - ``[msg]`` - The custom error message. Must be less than 1000 characters. Omit to reset to the default one.
+
 .. _core-command-set-fuzzy:
 
 """""""""

redbot/cogs/trivia/session.py

@@ -118,13 +118,12 @@ class TriviaSession:
             self.stop()
         except Exception as exc:
             LOG.error("A trivia session has encountered an error.\n", exc_info=exc)
-            asyncio.create_task(
+            msg = _("An unexpected error occurred in the trivia session.")
-                self.ctx.send(
+            if self.ctx.author.id in self.ctx.bot.owner_ids:
-                    _(
+                msg = _(
                     "An unexpected error occurred in the trivia session.\nCheck your console or logs for details."
                 )
-                )
+            asyncio.create_task(self.ctx.send(msg))
-            )
             self.stop()
 
     async def run(self):

redbot/core/bot.py

@@ -134,6 +134,7 @@ class Red(
             invite_commands_scope=False,
             disabled_commands=[],
             disabled_command_msg="That command is disabled.",
+            invoke_error_msg=None,
             extra_owner_destinations=[],
             owner_opt_out_list=[],
             last_system_info__python_version=[3, 7],

redbot/core/core_commands.py

@@ -3646,7 +3646,7 @@ class Core(commands.commands._RuleDropper, commands.Cog, CoreLogic):
 
     @_set.command(name="usebuttons")
     @checks.is_owner()
-    async def use_buttons(self, ctx: commands.Context, use_buttons: bool = None):
+    async def _set_usebuttons(self, ctx: commands.Context, use_buttons: bool = None):
         """
         Set a global bot variable for using buttons in menus.
 
@@ -3670,6 +3670,35 @@ class Core(commands.commands._RuleDropper, commands.Cog, CoreLogic):
         else:
             await ctx.send(_("I will not use buttons on basic menus."))
 
+    @_set.command(name="errormsg")
+    @commands.is_owner()
+    async def _set_errormsg(self, ctx: commands.Context, *, msg: str = None):
+        """
+        Set the message that will be sent on uncaught bot errors.
+
+        To include the command name in the message, use the `{command}` placeholder.
+
+        If you omit the `msg` argument, the message will be reset to the default one.
+
+        **Examples:**
+            - `[p]set errormsg` - Resets the error message back to the default: "Error in command '{command}'.". If the command invoker is one of the bot owners, the message will also include "Check your console or logs for details.".
+            - `[p]set errormsg Oops, the command {command} has failed! Please try again later.` - Sets the error message to a custom one.
+
+        **Arguments:**
+            - `[msg]` - The custom error message. Must be less than 1000 characters. Omit to reset to the default one.
+        """
+        if msg is not None and len(msg) >= 1000:
+            return await ctx.send(_("The message must be less than 1000 characters."))
+
+        if msg is not None:
+            await self.bot._config.invoke_error_msg.set(msg)
+            content = _("Succesfully updated the error message.")
+        else:
+            await self.bot._config.invoke_error_msg.clear()
+            content = _("Successfully reset the error message back to the default one.")
+
+        await ctx.send(content)
+
     @commands.group()
     @checks.is_owner()
     async def helpset(self, ctx: commands.Context):

redbot/core/events.py

@@ -266,16 +266,21 @@ def init_events(bot, cli_flags):
                 "Exception in command '{}'".format(ctx.command.qualified_name),
                 exc_info=error.original,
             )
-
-            message = _(
-                "Error in command '{command}'. Check your console or logs for details."
-            ).format(command=ctx.command.qualified_name)
             exception_log = "Exception in command '{}'\n" "".format(ctx.command.qualified_name)
             exception_log += "".join(
                 traceback.format_exception(type(error), error, error.__traceback__)
             )
             bot._last_exception = exception_log
-            await ctx.send(inline(message))
+
+            message = await bot._config.invoke_error_msg()
+            if not message:
+                if ctx.author.id in bot.owner_ids:
+                    message = inline(
+                        _("Error in command '{command}'. Check your console or logs for details.")
+                    )
+                else:
+                    message = inline(_("Error in command '{command}'."))
+            await ctx.send(message.replace("{command}", ctx.command.qualified_name))
         elif isinstance(error, commands.CommandNotFound):
             help_settings = await HelpSettings.from_context(ctx)
             fuzzy_commands = await fuzzy_command_search(