package fibonacci
import (
diff "0dev.org/diff"
"bytes"
"io"
"strings"
"testing"
)
func TestNumbers(t *testing.T) {
n := New(32)
expected := []uint64{1, 1, 2, 3, 5, 8, 13, 21}
for i, v := range expected {
if f := n[i]; f != v {
t.Error("Unexpected value for", i, f, "expected", v)
}
}
}
func TestCoding(t *testing.T) {
n := New(32)
for i := uint64(0); i < 4096; i++ {
enc, encLen := n.Code(i)
dec, decLen := n.Decode(enc)
if i != dec {
t.Errorf("Unexpected value for %d - enc is %b, dec is %d\n", i, enc, dec)
}
if encLen != decLen {
t.Errorf("Unexpected difference between encoded and decoded lengths.", encLen, decLen)
}
}
}
func TestWriterReader(t *testing.T) {
var (
buf bytes.Buffer
w io.Writer = Encoder(&buf)
input []byte = make([]byte, 256)
fib Numbers = New(16)
)
for i := uint64(0); i < 256; i++ {
input[i] = byte(i)
}
// Write the input
count, err := w.Write(input)
if count != len(input) {
t.Error("Unexpected write count", count)
}
if err != nil {
t.Error("Unexpected write error", err.Error())
}
// Flush remaining bits
count, err = w.Write(nil)
if count != 0 {
t.Error("Unexpected write count while flushing", count)
}
if err != nil {
t.Error("Unexpected write error while flushing", err.Error())
}
var output string
for _, v := range buf.Bytes() {
output += u2s(uint64(v), 8)
}
for i, v := range input {
c, l := fib.Code(uint64(v))
vs := u2s(c, l)
if loc := strings.Index(output, vs); loc != 0 {
t.Fatal("Unexpected location for", i, "value", vs)
}
output = output[len(vs):]
}
var (
in *bytes.Reader = bytes.NewReader(buf.Bytes())
r io.Reader = Decoder(in)
out bytes.Buffer
)
io.Copy(&out, r)
decoded := out.Bytes()
delta := diff.Diff(diff.D{Len1: len(decoded), Len2: len(input), EqualFunc: func(i, j int) bool {
return decoded[i] == input[j]
}})
if len(delta.Added) > 0 || len(delta.Removed) > 0 {
t.Error("Differences detected ", delta)
}
}
func u2s(b uint64, l byte) (result string) {
for i := byte(0); i < l; i++ {
if (b & 1) > 0 {
result += "1"
} else {
result += "0"
}
b >>= 1
}
return
}