diff --git a/types/pusher-js/index.d.ts b/types/pusher-js/index.d.ts
index f73a84ee52..a09c352386 100644
--- a/types/pusher-js/index.d.ts
+++ b/types/pusher-js/index.d.ts
@@ -8,6 +8,8 @@ declare namespace pusher {
     interface PusherStatic {
         logToConsole: boolean;
         log: (msg: string) => void;
+        instances: Pusher[];
+        isReady: boolean;
         new (apiKey: string, config?: Config): Pusher;
     }
 
diff --git a/types/pusher-js/pusher-js-tests.ts b/types/pusher-js/pusher-js-tests.ts
index 7381c48e73..29a3f693e8 100644
--- a/types/pusher-js/pusher-js-tests.ts
+++ b/types/pusher-js/pusher-js-tests.ts
@@ -13,6 +13,7 @@ var pusher: Pusher.Pusher;
 //
 
 Pusher.logToConsole = true;
+Pusher.instances = [];
 
 Pusher.log = (msg) => {
     console.log(msg);
@@ -26,6 +27,8 @@ pusher = new Pusher(APP_KEY, {
     authEndpoint: "http://example.com/pusher/auth"
 });
 
+console.assert(!!Pusher.instances.length, "Pusher.instances not filling with new instances");
+
 pusher = new Pusher(APP_KEY, {
     auth: {
         params: { foo: "bar" },