Class FakeTransport

tests/host/ipc/ipc_client_test.cpp:95–118

Fake transport: `inbound` is a queue of bytes handed out (possibly short) via receive(); sent frames are recorded verbatim in `sends`.

// Fake transport: `inbound` is a queue of bytes handed out (possibly short)
// via receive(); sent frames are recorded verbatim in `sends`.
struct FakeTransport final : ITransport {
    std::vector<std::byte> inbound;
    std::size_t pos = 0;
    std::vector<std::vector<std::byte>> sends;

    void send(std::span<const std::byte> d) override {
        sends.emplace_back(d.begin(), d.end());
    }

    std::size_t receive(std::span<std::byte> dst) override {
        const std::size_t n = (std::min)(dst.size(), inbound.size() - pos);
        std::memcpy(dst.data(), inbound.data() + pos, n);
        pos += n;
        return n; // may short-read
    }

    bool has_data() const override {
        return pos < inbound.size();
    }

    void feed(const std::vector<std::byte>& f) {
        inbound.insert(inbound.end(), f.begin(), f.end());
    }
};

// Captures the bytes a MessageComposer would send, without a real socket.
static std::vector<std::byte> frame(const MessageComposer& c) {