Default ircOptions.encoding to utf-8 if node-irc can convert encodings

Also warn when started if the IRC library cannot convert between
encodings, in case users rely on this behavior.

Author: Throne3d

README.md

@@ -100,7 +100,8 @@ To retrieve a discord channel ID, write `\#channel` on the relevant server – i
 
 ### Encodings
 
-If you encounter trouble with some characters being corrupted from some clients (particularly umlauted characters, such as `ä` or `ö`), try installing the optional dependencies `iconv` and `node-icu-charset-detector`, then adding `"encoding": "utf-8"` to your `ircOptions` object.
+If you encounter trouble with some characters being corrupted from some clients (particularly umlauted characters, such as `ä` or `ö`), try installing the optional dependencies `iconv` and `node-icu-charset-detector`.
+The bot will produce a warning when started if the IRC library is unable to convert between encodings.
 
 Further information can be found in [the installation section of irc-upd](https://github.com/Throne3d/node-irc#character-set-detection).
 

lib/bot.js

@@ -91,6 +91,15 @@ class Bot {
       ...this.ircOptions
     };
 
+    // default encoding to UTF-8 so messages to Discord aren't corrupted
+    if (!('encoding' in ircOptions)) {
+      if (irc.canConvertEncoding()) {
+        ircOptions.encoding = 'utf-8';
+      } else {
+        logger.warn('Cannot convert message encoding; you may encounter corrupted characters with non-English text.');
+      }
+    }
+
     this.ircClient = new irc.Client(this.server, this.nickname, ircOptions);
     this.attachListeners();
   }