}
	})

	t.Run("NegativeSize", func(t *testing.T) {
		tw := NewWriter(new(bytes.Buffer))
		hdr := &Header{Name: "small.txt", Size: -1}
		if err := tw.WriteHeader(hdr); err == nil {
			t.Fatalf("WriteHeader() = nil, want non-nil error")
		}
	})

	t.Run("BeforeHeader", func(t *testing.T) {
		tw := NewWriter(new(bytes.Buffer))
		if _, err := tw.Write([]byte("Kilts")); err != ErrWriteTooLong {

	// write a zip file
	archive := new(bytes.Buffer)
	w := NewWriter(archive)

	for i := range files {
		f := &files[i]
		f.crc32 = crc32.ChecksumIEEE(f.content)
		size := uint64(len(f.content))
		f.uncompressedSize = size
		f.compressedSize = size

		var compressedContent []byte
		if f.method == Deflate {
			var buf bytes.Buffer
			w, err := flate.NewWriter(&buf, flate.BestSpeed)
			if err != nil {