Issue 2148 - Rewrite the testpages test suite

pages/filters/websocket.tmpl

+title = $websocket - ABP Test Pages
+template = testcase
+
+{% set testcase_moreinfo = [
+  ("Filter Options", "https://adblockplus.org/filters#options"),
+] %}
+
+
+<script>
+function pagelog(message) {
+  var log = document.getElementById("testcase-fo-websocket");
+  log.innerText = log.innerText + message + "\n";
+  console.log(message);
+}
+
+function ws_open(evt) {
+  pagelog("Connected");
+  websocket.send("Test message was echoed back");
+}
+function ws_close(evt) {
+  pagelog("Disconnected");
+}
+function ws_message(evt) {
+  pagelog("Received message: ");
+  pagelog(evt.data);
+}
+function ws_error(evt) {
+  pagelog("WebSocket error / Blocked");
+}
+
+function ws_disconnect()
+{
+  websocket.close();
+}
+
+function ws_connect() {
+  var url ="wss://echo.websocket.org";
+  websocket = new WebSocket(url);
+  websocket.onopen = function(evt) { ws_open(evt) };
+  websocket.onclose = function(evt) { ws_disconnect(evt) };
+  websocket.onmessage = function(evt) { ws_message(evt) };
+  websocket.onerror = function(evt) { ws_error(evt) };
+}
+
+document.addEventListener('DOMContentLoaded', ws_connect, false);
+</script>
+
+<section class="site-panel">
+  <h2>$websocket</h2>
+  <p>Check that usage of the $websocket filter option works as expected.</p>
+</section>
+
+<section class="site-panel">
+  <h2>Test case</h2>
+  <div class="testcase-container">
+   <div class="testcase-row"><h3>WebSocket Request</h3><div id="testcase-fo-websocket"></div></div>
+  </div>
+  <h3>Filters</h3>
+  $websocket,domain=testpages.adblockplus.org
+</section>