produce a decent error when connecting with the wrong version

src/client/versionChecking.js

@@ -0,0 +1,11 @@
+module.exports = function(client,options) {
+  client.on("disconnect",message => {
+    if(!message.reason)
+      return;
+    const versionRequired=/Outdated client! Please use (.+)/.exec(JSON.parse(message.reason).text);
+    if(!versionRequired)
+      return;
+    client.emit("error",new Error("This server is version "+versionRequired[1]+
+      ", you are using version "+client.version+", please specify the correct version in the options."))
+  })
+};

src/createClient.js

@@ -12,6 +12,7 @@ const play = require('./client/play');
 const tcp_dns = require('./client/tcp_dns');
 const autoVersion = require('./client/autoVersion');
 const pluginChannels = require('./client/pluginChannels');
+const versionChecking = require('./client/versionChecking');
 
 module.exports=createClient;
 
@@ -38,6 +39,7 @@ function createClient(options) {
   play(client, options);
   compress(client, options);
   pluginChannels(client, options);
+  versionChecking(client,options);
 
   return client;
 }

test/clientTest.js

@@ -221,5 +221,29 @@ mc.supportedVersions.forEach(function(supportedVersion) {
         });
       });
     });
+
+    it("produce a decent error when connecting with the wrong version",function(done) {
+      wrap.startServer({
+        'online-mode': 'false',
+        'server-port':PORT
+      }, function(err) {
+        if(err)
+          return done(err);
+        var client = mc.createClient({
+          username: 'Player',
+          version: version.minecraftVersion=="1.8.8" ? "1.11.2" : "1.8.8",
+          port:PORT
+        });
+        client.once("error",function(err) {
+          if(err.message.startsWith("This server is version")) {
+            console.log("Correctly got an error for wrong version : "+err.message);
+            done();
+          }
+          else {
+            done(err);
+          }
+        });
+      })
+    })
   });
 });