Added RLE compression. Closes #171

compression/rle/read_write_test.go

@@ -0,0 +1,93 @@
+package rle
+
+import (
+	"bytes"
+	"testing"
+
+	"github.com/ethereum/go-ethereum/crypto"
+)
+
+func TestDecompressSimple(t *testing.T) {
+	res, err := Decompress([]byte{token, 0xfd})
+	if err != nil {
+		t.Error(err)
+	}
+	if bytes.Compare(res, crypto.Sha3([]byte(""))) != 0 {
+		t.Error("empty sha3", res)
+	}
+
+	res, err = Decompress([]byte{token, 0xfe})
+	if err != nil {
+		t.Error(err)
+	}
+	if bytes.Compare(res, crypto.Sha3([]byte{0x80})) != 0 {
+		t.Error("0x80 sha3", res)
+	}
+
+	res, err = Decompress([]byte{token, 0xff})
+	if err != nil {
+		t.Error(err)
+	}
+	if bytes.Compare(res, []byte{token}) != 0 {
+		t.Error("token", res)
+	}
+
+	res, err = Decompress([]byte{token, 12})
+	if err != nil {
+		t.Error(err)
+	}
+	if bytes.Compare(res, make([]byte, 10)) != 0 {
+		t.Error("10 * zero", res)
+	}
+}
+
+func TestDecompressMulti(t *testing.T) {
+	res, err := Decompress([]byte{token, 0xfd, token, 0xfe, token, 12})
+	if err != nil {
+		t.Error(err)
+	}
+
+	var exp []byte
+	exp = append(exp, crypto.Sha3([]byte(""))...)
+	exp = append(exp, crypto.Sha3([]byte{0x80})...)
+	exp = append(exp, make([]byte, 10)...)
+
+	if bytes.Compare(res, res) != 0 {
+		t.Error("Expected", exp, "result", res)
+	}
+}
+
+func TestCompressSimple(t *testing.T) {
+	res := Compress([]byte{0, 0, 0, 0, 0})
+	if bytes.Compare(res, []byte{token, 7}) != 0 {
+		t.Error("5 * zero", res)
+	}
+
+	res = Compress(crypto.Sha3([]byte("")))
+	if bytes.Compare(res, []byte{token, emptyShaToken}) != 0 {
+		t.Error("empty sha", res)
+	}
+
+	res = Compress(crypto.Sha3([]byte{0x80}))
+	if bytes.Compare(res, []byte{token, emptyListShaToken}) != 0 {
+		t.Error("empty list sha", res)
+	}
+
+	res = Compress([]byte{token})
+	if bytes.Compare(res, []byte{token, tokenToken}) != 0 {
+		t.Error("token", res)
+	}
+}
+
+func TestCompressMulti(t *testing.T) {
+	in := []byte{0, 0, 0, 0, 0}
+	in = append(in, crypto.Sha3([]byte(""))...)
+	in = append(in, crypto.Sha3([]byte{0x80})...)
+	in = append(in, token)
+	res := Compress(in)
+
+	exp := []byte{token, 7, token, emptyShaToken, token, emptyListShaToken, token, tokenToken}
+	if bytes.Compare(res, exp) != 0 {
+		t.Error("expected", exp, "got", res)
+	}
+}