License info command (#3090)

* Adds a licenseinfo command

* good enough for now

* changelog

* *sigh* Fine, have it your way Draper

* thanks Flame

redbot/core/commands/commands.py

@@ -699,3 +699,29 @@ def get_command_disabler(guild: discord.Guild) -> Callable[["Context"], Awaitabl
 
         __command_disablers[guild] = disabler
         return disabler
+
+
+# This is intentionally left out of `__all__` as it is not intended for general use
+class _AlwaysAvailableCommand(Command):
+    """
+    This should be used only for informational commands
+    which should not be disabled or removed
+
+    These commands cannot belong to a cog.
+
+    These commands do not respect most forms of checks, and
+    should only be used with that in mind.
+
+    This particular class is not supported for 3rd party use
+    """
+
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+        if self.cog is not None:
+            raise TypeError("This command may not be added to a cog")
+
+    async def can_run(self, ctx, *args, **kwargs) -> bool:
+        return not ctx.author.bot
+
+    async def _verify_checks(self, ctx) -> bool:
+        return not ctx.author.bot

redbot/core/core_commands.py

@@ -1136,7 +1136,7 @@ class Core(commands.Cog, CoreLogic):
     @checks.is_owner()
     async def api(self, ctx: commands.Context, service: str, *, tokens: TokenConverter):
         """Set various external API tokens.
-        
+
         This setting will be asked for by some 3rd party cogs and some core cogs.
 
         To add the keys provide the service name and the tokens as a comma separated
@@ -1162,7 +1162,7 @@ class Core(commands.Cog, CoreLogic):
         Allows the help command to be sent as a paginated menu instead of seperate
         messages.
 
-        This defaults to False. 
+        This defaults to False.
         Using this without a setting will toggle.
         """
         if use_menus is None:
@@ -1907,6 +1907,12 @@ class Core(commands.Cog, CoreLogic):
             )
             return
 
+        if isinstance(command_obj, commands.commands._AlwaysAvailableCommand):
+            await ctx.send(
+                _("This command is designated as being always available and cannot be disabled.")
+            )
+            return
+
         async with ctx.bot._config.disabled_commands() as disabled_commands:
             if command not in disabled_commands:
                 disabled_commands.append(command_obj.qualified_name)
@@ -1935,6 +1941,12 @@ class Core(commands.Cog, CoreLogic):
             )
             return
 
+        if isinstance(command_obj, commands.commands._AlwaysAvailableCommand):
+            await ctx.send(
+                _("This command is designated as being always available and cannot be disabled.")
+            )
+            return
+
         if command_obj.requires.privilege_level > await PrivilegeLevel.from_ctx(ctx):
             await ctx.send(_("You are not allowed to disable that command."))
             return
@@ -2215,3 +2227,21 @@ class Core(commands.Cog, CoreLogic):
     async def rpc_reload(self, request):
         await self.rpc_unload(request)
         await self.rpc_load(request)
+
+
+# Removing this command from forks is a violation of the GPLv3 under which it is licensed.
+# Otherwise interfering with the ability for this command to be accessible is also a violation.
+@commands.command(cls=commands.commands._AlwaysAvailableCommand, name="licenseinfo", i18n=_)
+async def license_info_command(ctx):
+    """
+    Get info about Red's licenses
+    """
+
+    message = (
+        "This bot is an instance of Red-DiscordBot (hereafter refered to as Red)\n"
+        "Red is a free and open source application made available to the public and "
+        "licensed under the GNU GPLv3. The full text of this license is available to you at "
+        "<https://github.com/Cog-Creators/Red-DiscordBot/blob/V3/develop/LICENSE>"
+    )
+    await ctx.send(message)
+    # We need a link which contains a thank you to other projects which we use at some point.