func (w *writeCrasher) Read(p []byte) (int, error) {
	<-w.done
	return 0, io.EOF
}

func (writeCrasher) Write(p []byte) (int, error) {
	return 0, errors.New("fake write failure")
}

func TestClientWriteError(t *testing.T) {
	w := &writeCrasher{done: make(chan bool)}
	c := NewClient(w)
	defer c.Close()

	res := false
	err := c.Call("foo", 1, &res)
	if err == nil {
		t.Fatal("expected error")
	}