}

	// test read of each file
	for i, ft := range zt.File {
		readTestFile(t, zt, ft, z.File[i], raw)
	}
	if t.Failed() {
		return
	}

	// test simultaneous reads
	n := 0
	done := make(chan bool)
	for i := 0; i < 5; i++ {
		for j, ft := range zt.File {
			go func(j int, ft ZipTestFile) {
				readTestFile(t, zt, ft, z.File[j], raw)
				done <- true
			}(j, ft)

	withOut.n, withOut.err = io.Copy(discard, justReader{NewReader(nil)})
	if with != withOut {
		t.Errorf("behavior differs: with = %#v; without: %#v", with, withOut)
	}
}

// tests that Len is affected by reads, but Size is not.
func TestReaderLenSize(t *testing.T) {
	r := NewReader([]byte("abc"))
	io.CopyN(io.Discard, r, 1)
	if r.Len() != 2 {
		t.Errorf("Len = %d; want 2", r.Len())
	}
	if r.Size() != 3 {