func TestTransportFrameBufferReuse(t *testing.T) {
        st := newServerTester(t, func(w http.ResponseWriter, r *http.Request) {}, optOnlyServer)
        defer st.Close()

        tr := &Transport{TLSClientConfig: tlsConfigInsecure}
        defer tr.CloseIdleConnections()

        filler := hex.EncodeToString([]byte(randString(2048)))
        var wg sync.WaitGroup
        defer wg.Wait()
        for i := 0; i < 10; i++ {
                wg.Add(1)
                go func() {
                        defer wg.Done()
                        req, err := http.NewRequest("POST", st.ts.URL, strings.NewReader(filler))
                        if err != nil {
                                t.Fatal(err)
                        }
                        req.Header.Set("Big", filler)
                        req.Trailer = make(http.Header)
                        req.Trailer.Set("Big", filler)
                        res, err := tr.RoundTrip(req)
                        if err != nil {
                                t.Fatal(err)
                        }
                        if got, want := res.StatusCode, 200; got != want {
                                t.Errorf("StatusCode = %v; want %v", got, want)
                        }
                        if res != nil && res.Body != nil {
                                res.Body.Close()
                        }
                }()
        }
}