package predictor
import (
diff "0dev.org/diff"
"bytes"
"io/ioutil"
"testing"
)
// Sample input from RFC1978 - PPP Predictor Compression Protocol
var input = []byte{0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x0a,
0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x0a,
0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x0a,
0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x0a,
0x41, 0x42, 0x41, 0x42, 0x41, 0x42, 0x41, 0x0a,
0x42, 0x41, 0x42, 0x41, 0x42, 0x41, 0x42, 0x0a,
0x78, 0x78, 0x78, 0x78, 0x78, 0x78, 0x78, 0x0a}
// Sample output from RFC1978 - PPP Predictor Compression Protocol
var output = []byte{0x60, 0x41, 0x41, 0x41, 0x41, 0x41, 0x0a, 0x60,
0x41, 0x41, 0x41, 0x41, 0x41, 0x0a, 0x6f, 0x41,
0x0a, 0x6f, 0x41, 0x0a, 0x41, 0x42, 0x41, 0x42,
0x41, 0x42, 0x0a, 0x60, 0x42, 0x41, 0x42, 0x41,
0x42, 0x0a, 0x60, 0x78, 0x78, 0x78, 0x78, 0x78, 0x0a}
func TestCompressor(t *testing.T) {
var (
buf bytes.Buffer
err error
)
out := Compressor(&buf)
err = out(input)
if err != nil {
t.Error(err)
}
err = out(nil)
if err != nil {
t.Error(err)
}
result := buf.Bytes()
delta := diff.Diff(diff.D{len(result), len(output), func(i, j int) bool { return result[i] == output[j] }})
if len(delta.Added) > 0 || len(delta.Removed) > 0 {
t.Error("Unexpected compressed output", delta)
}
}
func TestDecompressor(t *testing.T) {
in := Decompressor(bytes.NewReader(output))
result, err := ioutil.ReadAll(in)
if err != nil {
t.Error("Unexpected error while decompressing", err)
}
delta := diff.Diff(diff.D{len(result), len(input),
func(i, j int) bool { return result[i] == input[j] }})
if len(delta.Added) > 0 || len(delta.Removed) > 0 {
t.Error("Unexpected decompressed output", delta)
}
}
func TestPartial(t *testing.T) {
var (
input []byte = []byte{0, 1, 2, 3, 4, 5, 6}
buf bytes.Buffer
err error
)
out := Compressor(&buf)
err = out(input)
if err != nil {
t.Error(err)
}
err = out(nil)
if err != nil {
t.Error(err)
}
compressed := buf.Bytes()
decompressed, err := ioutil.ReadAll(Decompressor(bytes.NewReader(compressed)))
delta := diff.Diff(diff.D{len(input), len(decompressed),
func(i, j int) bool { return input[i] == decompressed[j] }})
if len(delta.Added) > 0 || len(delta.Removed) > 0 {
t.Error("Unexpected decompressed output", delta)
t.Errorf("%#x", input)
t.Errorf("%#x", decompressed)
}
}