1 files changed, 87 insertions, 0 deletions
diff --git a/netwerk/test/mochitests/test_accept_header.html b/netwerk/test/mochitests/test_accept_header.html
new file mode 100644
index 0000000000..0acae2a825
--- /dev/null
+++ b/netwerk/test/mochitests/test_accept_header.html
@@ -0,0 +1,87 @@
+<!DOCTYPE HTML>
+<html>
+<head>
+  <title>Accept header</title>
+  <script src="/tests/SimpleTest/SimpleTest.js"></script>
+  <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css"/>
+</head>
+<body>
+<script>
+SimpleTest.requestCompleteLog();
+
+// All the requests are sent to test_accept_header.sjs which will return
+// different content based on the queryString. When the queryString is 'get',
+// test_accept_header.sjs returns a JSON object with the latest request and its
+// accept header value.
+
+function test_last_request_and_continue(query, expected) {
+  fetch("test_accept_header.sjs?get").then(r => r.json()).then(json => {
+    is(json.type, query, "Expected: " + query);
+    is(json.accept, expected, "Accept header: " + expected);
+    next();
+  });
+}
+
+function test_iframe() {
+  let ifr = document.createElement("iframe");
+  ifr.src = "test_accept_header.sjs?iframe";
+  ifr.onload = () => {
+    test_last_request_and_continue("iframe", "text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,*/*;q=0.8");
+  };
+  document.body.appendChild(ifr);
+}
+
+function test_image() {
+  let i = new Image();
+  i.src = "test_accept_header.sjs?image";
+  i.onload = function() {
+    // Fetch spec says we should have: "image/png,image/svg+xml,image/*;q=0.8,*/*;q=0.5"
+    test_last_request_and_continue("image", "image/avif,image/webp,*/*");
+  }
+}
+
+function test_style() {
+  let head = document.getElementsByTagName("head")[0];
+  let link = document.createElement("link");
+  link.rel = "stylesheet";
+  link.type = "text/css";
+  link.href = "test_accept_header.sjs?style";
+  link.onload = () => {
+    test_last_request_and_continue("style", "text/css,*/*;q=0.1");
+  };
+  head.appendChild(link);
+}
+
+function test_worker() {
+  let w = new Worker("test_accept_header.sjs?worker");
+  w.onmessage = function() {
+    test_last_request_and_continue("worker", "*/*");
+  }
+}
+
+let tests = [
+  test_iframe,
+  test_image,
+  test_style,
+  test_worker,
+];
+
+function next() {
+  if (!tests.length) {
+    SimpleTest.finish();
+    return;
+  }
+
+  let test = tests.shift();
+  test();
+}
+
+SimpleTest.waitForExplicitFinish();
+
+SpecialPowers.pushPrefEnv({ "set": [
+  [ "dom.enable_performance_observer", true ]
+]}, next);
+
+</script>
+</body>
+</html>