1 files changed, 33 insertions, 0 deletions
diff --git a/testing/web-platform/tests/html/infrastructure/safe-passing-of-structured-data/shared-array-buffers/no-coop-coep.https.any.js b/testing/web-platform/tests/html/infrastructure/safe-passing-of-structured-data/shared-array-buffers/no-coop-coep.https.any.js
new file mode 100644
index 0000000000..0db16fd6f7
--- /dev/null
+++ b/testing/web-platform/tests/html/infrastructure/safe-passing-of-structured-data/shared-array-buffers/no-coop-coep.https.any.js
@@ -0,0 +1,33 @@
+// META: global=window,worker
+
+test(() => {
+  // See https://github.com/whatwg/html/issues/5380 for why not `new SharedArrayBuffer()`
+  assert_equals(globalThis.SharedArrayBuffer, undefined);
+  assert_false("SharedArrayBuffer" in globalThis);
+}, "SharedArrayBuffer constructor does not exist without COOP+COEP");
+
+test(() => {
+  // See https://github.com/whatwg/html/issues/5380 for why not `new SharedArrayBuffer()`
+  const sab = new WebAssembly.Memory({ shared:true, initial:1, maximum:1 }).buffer;
+  const channel = new MessageChannel();
+  assert_throws_dom("DataCloneError", () => channel.port1.postMessage(sab));
+}, "SharedArrayBuffer over MessageChannel without COOP+COEP");
+
+test(() => {
+  // See https://github.com/whatwg/html/issues/5380 for why not `new SharedArrayBuffer()`
+  const sab = new WebAssembly.Memory({ shared:true, initial:1, maximum:1 }).buffer;
+  const channel = new BroadcastChannel("Is mir egal");
+  assert_throws_dom("DataCloneError", () => channel.postMessage(sab));
+}, "SharedArrayBuffer over BroadcastChannel without COOP+COEP");
+
+if (self.GLOBAL.isWindow()) {
+  test(() => {
+    // See https://github.com/whatwg/html/issues/5380 for why not `new SharedArrayBuffer()`
+    const sab = new WebAssembly.Memory({ shared:true, initial:1, maximum:1 }).buffer;
+    assert_throws_dom("DataCloneError", () => self.postMessage(sab));
+  }, "SharedArrayBuffer over postMessage() without COOP+COEP");
+}
+
+test(() => {
+  assert_false(self.crossOriginIsolated);
+}, "Bonus: self.crossOriginIsolated");