1 files changed, 47 insertions, 0 deletions
diff --git a/testing/web-platform/tests/html/browsers/browsing-the-web/back-forward-cache/resources/inflight-fetch-helper.js b/testing/web-platform/tests/html/browsers/browsing-the-web/back-forward-cache/resources/inflight-fetch-helper.js
new file mode 100644
index 0000000000..7832003b76
--- /dev/null
+++ b/testing/web-platform/tests/html/browsers/browsing-the-web/back-forward-cache/resources/inflight-fetch-helper.js
@@ -0,0 +1,47 @@
+// Delay after fetch start:
+// - 0.0 seconds: before BFCache
+// - 2.0 seconds: when in BFCache
+// - 3.5 seconds: after restored from BFCache
+function runTest(urlToFetch, hasCSP, shouldSucceed, description) {
+  runBfcacheTest({
+    funcBeforeNavigation: async (urlToFetch, hasCSP) => {
+      if (hasCSP) {
+        // Set CSP.
+        const meta = document.createElement('meta');
+        meta.setAttribute('http-equiv', 'Content-Security-Policy');
+        meta.setAttribute('content', "connect-src 'self'");
+        document.head.appendChild(meta);
+      }
+
+      // Initiate a `fetch()`.
+      window.fetchPromise = fetch(urlToFetch);
+
+      // Wait for 0.5 seconds to receive response headers for the fetch()
+      // before BFCache, if any.
+      await new Promise(resolve => setTimeout(resolve, 500));
+    },
+    argsBeforeNavigation: [urlToFetch, hasCSP],
+    funcBeforeBackNavigation: () => {
+      // Wait for 2 seconds before back navigating to pageA.
+      return new Promise(resolve => setTimeout(resolve, 2000));
+    },
+    funcAfterAssertion: async (pageA, pageB, t) => {
+      // Wait for fetch() completion and check the result.
+      const result = pageA.execute_script(
+          () => window.fetchPromise.then(r => r.text()));
+      if (shouldSucceed) {
+        assert_equals(
+          await result,
+          'Body',
+          'Fetch should complete successfully after restored from BFCache');
+      } else {
+        await promise_rejects_js(t, TypeError, result,
+          'Fetch should fail after restored from BFCache');
+      }
+    }
+  }, 'Eligibility (in-flight fetch): ' + description);
+}
+
+const url = new URL('../resources/slow.py', location);
+const sameOriginUrl = url.href;
+const crossSiteUrl = originCrossSite + url.pathname;