1 files changed, 29 insertions, 0 deletions
diff --git a/devtools/client/application/test/browser/resources/service-workers/controlled-install-sw.js b/devtools/client/application/test/browser/resources/service-workers/controlled-install-sw.js
new file mode 100644
index 0000000000..d0a70a5312
--- /dev/null
+++ b/devtools/client/application/test/browser/resources/service-workers/controlled-install-sw.js
@@ -0,0 +1,29 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+"use strict";
+
+// Copied from shared-head.js
+function waitUntil(predicate, interval = 10) {
+  if (predicate()) {
+    return Promise.resolve(true);
+  }
+  return new Promise(resolve => {
+    setTimeout(function () {
+      waitUntil(predicate, interval).then(() => resolve(true));
+    }, interval);
+  });
+}
+
+// this flag will be flipped externally from controlled-install.html
+// by sending a message event to the worker
+let canInstall = false;
+self.addEventListener("message", event => {
+  if (event.data === "install-service-worker") {
+    canInstall = true;
+  }
+});
+
+self.addEventListener("install", event => {
+  event.waitUntil(waitUntil(() => canInstall));
+});