From 31cb10bcff05725f8ee55e03458f5db69f3b5248 Mon Sep 17 00:00:00 2001
From: Tejas Dinkar <tejas@gja.in>
Date: Sun, 27 Jan 2019 09:01:27 +0530
Subject: [PATCH] fix(Example): Apparently response headers are immutable.
 Closes [#27] (#28)

---
 examples/unit-test-a-worker/worker.js | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/examples/unit-test-a-worker/worker.js b/examples/unit-test-a-worker/worker.js
index 5e64e95..36f9c0f 100644
--- a/examples/unit-test-a-worker/worker.js
+++ b/examples/unit-test-a-worker/worker.js
@@ -1,3 +1,6 @@
+// Add any more global vars (like Request, Response) to the below list as they are used
+/* global addEventListener fetch Response Headers */
+
 addEventListener("fetch", e => {
   e.respondWith(fetchAndAddHeader(e.request));
 });
@@ -5,11 +8,17 @@ addEventListener("fetch", e => {
 async function fetchAndAddHeader(request) {
   const response = await fetch(request);
 
+  const headers = new Headers(response.headers);
+  
   if (response.status === 200) {
-    response.headers.set("Foo", "Bar");
+    headers.set("Foo", "Bar");
   } else {
-    response.headers.set("Foo", "Not Bar");
+    headers.set("Foo", "Not Bar");
   }
 
-  return response;
+  return new Response(response.body, {
+    headers: headers,
+    status: response.status,
+    statusText: response.statusText,
+  });
 }