for i := 0; i < 2; i++ {
			e = buf.Flush()
			if e != w.expect {
				t.Errorf("Flush %d/2 %v: got %v, wanted %v", i+1, w, e, w.expect)
			}
		}
	}
}

func TestNewReaderSizeIdempotent(t *testing.T) {
	const BufSize = 1000
	b := NewReaderSize(strings.NewReader("hello world"), BufSize)
	// Does it recognize itself?
	b1 := NewReaderSize(b, BufSize)
	if b1 != b {