diff --git a/tests/fake.websocket.js b/tests/fake.websocket.js
index a929a71f..d273fe07 100644
--- a/tests/fake.websocket.js
+++ b/tests/fake.websocket.js
@@ -55,11 +55,15 @@ export default class FakeWebSocket {
     }
 
     _receiveData(data) {
-        // Break apart the data to expose bugs where we assume data is
-        // neatly packaged
-        for (let i = 0;i < data.length;i++) {
-            let buf = data.slice(i, i+1);
-            this.onmessage(new MessageEvent("message", { 'data': buf.buffer }));
+        if (data.length < 4096) {
+            // Break apart the data to expose bugs where we assume data is
+            // neatly packaged
+            for (let i = 0;i < data.length;i++) {
+                let buf = data.slice(i, i+1);
+                this.onmessage(new MessageEvent("message", { 'data': buf.buffer }));
+            }
+        } else {
+            this.onmessage(new MessageEvent("message", { 'data': data.buffer }));
         }
     }
 }