return 10, nil
}

func TestWriterReadFromMustSetUnderlyingError(t *testing.T) {
	var wr = NewWriter(writerWithReadFromError{})
	if _, err := wr.ReadFrom(strings.NewReader("test2")); err == nil {
		t.Fatal("expected ReadFrom returns error, got nil")
	}
	if _, err := wr.Write([]byte("123")); err == nil {
		t.Fatal("expected Write returns error, got nil")
	}
}