1 files changed, 70 insertions, 0 deletions
diff --git a/testing/web-platform/tests/resource-timing/cross-origin-status-codes.html b/testing/web-platform/tests/resource-timing/cross-origin-status-codes.html
new file mode 100644
index 0000000000..197a766339
--- /dev/null
+++ b/testing/web-platform/tests/resource-timing/cross-origin-status-codes.html
@@ -0,0 +1,70 @@
+<!doctype html>
+<html>
+<head>
+<title>Resource Timing: PerformanceResourceTiming attributes shouldn't change
+  if the HTTP status code changes</title>
+<link rel="help" href="https://www.w3.org/TR/resource-timing-2/#sec-performanceresourcetiming"/>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src=/common/get-host-info.sub.js></script>
+</head>
+<body>
+<img id="img_200">
+<img id="img_307">
+<img id="img_404">
+<img id="img_502">
+<script id="script_200"></script>
+<script id="script_307"></script>
+<script id="script_404"></script>
+<script id="script_502"></script>
+<script>
+
+const listenForPerformanceEntries = num_expected => {
+  return new Promise(resolve => {
+    let results = [];
+    new PerformanceObserver(entryList => {
+      entryList.getEntries().forEach(entry => {
+        if (!entry.name.includes("status-code"))
+          return;
+
+        results.push(entry);
+        if (results.length == num_expected) {
+          resolve(results);
+        }
+      });
+    }).observe({entryTypes: ['resource']});
+  });
+}
+
+promise_test(async t => {
+  const destUrl = get_host_info().HTTP_REMOTE_ORIGIN + '/resource-timing/resources/';
+  const statusCodes = ['200', '307', '404', '502'];
+
+  let expected_entry_count = 0;
+  statusCodes.forEach(status => {
+    document.getElementById(`img_${status}`).src = `${destUrl}status-code.py?status=${status}`;
+    document.getElementById(`script_${status}`).src = `${destUrl}status-code.py?status=${status}&script=1`;
+    expected_entry_count += 2;
+  });
+
+  const entries = await listenForPerformanceEntries(expected_entry_count);
+
+  // We will check that the non-timestamp values of the entry match for all
+  // entries.
+  const keys = [
+    'entryType',
+    'nextHopProtocol',
+    'transferSize',
+    'encodedBodySize',
+    'decodedBodySize',
+  ];
+
+  const first = entries[0];
+  entries.slice(1).forEach(entry => {
+    keys.forEach(attribute => {
+      assert_equals(entry[attribute], first[attribute],
+        `There must be no discernible difference for the ${attribute} ` +
+        `attribute but found a difference for the ${entry.name} resource.`);
+  })});
+}, "Make sure cross origin resource fetch failures with different status codes are indistinguishable");
+</script>