getWriter();
    const receiverReader = receiverTransform.readable.getReader();

    senderTransform.setEncryptionKey(key);
    receiverTransform.setEncryptionKey(key);

    const chunk = new ArrayBuffer(8);

    // decryption should fail, leading to an empty array buffer.
    await receiverWriter.write(chunk);
    let received = await receiverReader.read();
    assert_equals(received.value.byteLength, 0);

    // We write again but this time with a chunk we can decrypt.
    await senderWriter.write(chunk);