!source: don't show source of messages you don't have access to; allow mods to use the command by default

backend/src/utils/canReadChannel.ts

@@ -0,0 +1,10 @@
+import { Constants, GuildChannel } from "eris";
+import { hasPermissions } from "./hasPermissions";
+
+export function canReadChannel(channel: GuildChannel, memberId: string) {
+  const channelPermissions = channel.permissionsOf(memberId);
+  return hasPermissions(channelPermissions, [
+    Constants.Permissions.readMessages,
+    Constants.Permissions.readMessageHistory,
+  ]);
+}