Subversion Repositories openrisc

// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

package ascii85

import (
        "bytes"
        "io"
        "io/ioutil"
        "testing"
)

type testpair struct {
        decoded, encoded string
}

var pairs = []testpair{
        // Wikipedia example
        {
                "Man is distinguished, not only by his reason, but by this singular passion from " +
                        "other animals, which is a lust of the mind, that by a perseverance of delight in " +
                        "the continued and indefatigable generation of knowledge, exceeds the short " +
                        "vehemence of any carnal pleasure.",
                "9jqo^BlbD-BleB1DJ+*+F(f,q/0JhKF<GL>Cj@.4Gp$d7F!,L7@<6@)/0JDEF<G%<+EV:2F!,\n" +
                        "O<DJ+*.@<*K0@<6L(Df-\\0Ec5e;DffZ(EZee.Bl.9pF\"AGXBPCsi+DGm>@3BB/F*&OCAfu2/AKY\n" +
                        "i(DIb:@FD,*)+C]U=@3BN#EcYf8ATD3s@q?d$AftVqCh[NqF<G:8+EV:.+Cf>-FD5W8ARlolDIa\n" +
                        "l(DId<j@<?3r@:F%a+D58'ATD4$Bl@l3De:,-DJs`8ARoFb/0JMK@qB4^F!,R<AKZ&-DfTqBG%G\n" +
                        ">uD.RTpAKYo'+CT/5+Cei#DII?(E,9)oF*2M7/c\n",
        },
}

var bigtest = pairs[len(pairs)-1]

func testEqual(t *testing.T, msg string, args ...interface{}) bool {
        if args[len(args)-2] != args[len(args)-1] {
                t.Errorf(msg, args...)
                return false
        }
        return true
}

func strip85(s string) string {
        t := make([]byte, len(s))
        w := 0
        for r := 0; r < len(s); r++ {
                c := s[r]
                if c > ' ' {
                        t[w] = c
                        w++
                }
        }
        return string(t[0:w])
}

func TestEncode(t *testing.T) {
        for _, p := range pairs {
                buf := make([]byte, MaxEncodedLen(len(p.decoded)))
                n := Encode(buf, []byte(p.decoded))
                buf = buf[0:n]
                testEqual(t, "Encode(%q) = %q, want %q", p.decoded, strip85(string(buf)), strip85(p.encoded))
        }
}

func TestEncoder(t *testing.T) {
        for _, p := range pairs {
                bb := &bytes.Buffer{}
                encoder := NewEncoder(bb)
                encoder.Write([]byte(p.decoded))
                encoder.Close()
                testEqual(t, "Encode(%q) = %q, want %q", p.decoded, strip85(bb.String()), strip85(p.encoded))
        }
}

func TestEncoderBuffering(t *testing.T) {
        input := []byte(bigtest.decoded)
        for bs := 1; bs <= 12; bs++ {
                bb := &bytes.Buffer{}
                encoder := NewEncoder(bb)
                for pos := 0; pos < len(input); pos += bs {
                        end := pos + bs
                        if end > len(input) {
                                end = len(input)
                        }
                        n, err := encoder.Write(input[pos:end])
                        testEqual(t, "Write(%q) gave error %v, want %v", input[pos:end], err, error(nil))
                        testEqual(t, "Write(%q) gave length %v, want %v", input[pos:end], n, end-pos)
                }
                err := encoder.Close()
                testEqual(t, "Close gave error %v, want %v", err, error(nil))
                testEqual(t, "Encoding/%d of %q = %q, want %q", bs, bigtest.decoded, strip85(bb.String()), strip85(bigtest.encoded))
        }
}

func TestDecode(t *testing.T) {
        for _, p := range pairs {
                dbuf := make([]byte, 4*len(p.encoded))
                ndst, nsrc, err := Decode(dbuf, []byte(p.encoded), true)
                testEqual(t, "Decode(%q) = error %v, want %v", p.encoded, err, error(nil))
                testEqual(t, "Decode(%q) = nsrc %v, want %v", p.encoded, nsrc, len(p.encoded))
                testEqual(t, "Decode(%q) = ndst %v, want %v", p.encoded, ndst, len(p.decoded))
                testEqual(t, "Decode(%q) = %q, want %q", p.encoded, string(dbuf[0:ndst]), p.decoded)
        }
}

func TestDecoder(t *testing.T) {
        for _, p := range pairs {
                decoder := NewDecoder(bytes.NewBufferString(p.encoded))
                dbuf, err := ioutil.ReadAll(decoder)
                if err != nil {
                        t.Fatal("Read failed", err)
                }
                testEqual(t, "Read from %q = length %v, want %v", p.encoded, len(dbuf), len(p.decoded))
                testEqual(t, "Decoding of %q = %q, want %q", p.encoded, string(dbuf), p.decoded)
                if err != nil {
                        testEqual(t, "Read from %q = %v, want %v", p.encoded, err, io.EOF)
                }
        }
}

func TestDecoderBuffering(t *testing.T) {
        for bs := 1; bs <= 12; bs++ {
                decoder := NewDecoder(bytes.NewBufferString(bigtest.encoded))
                buf := make([]byte, len(bigtest.decoded)+12)
                var total int
                for total = 0; total < len(bigtest.decoded); {
                        n, err := decoder.Read(buf[total : total+bs])
                        testEqual(t, "Read from %q at pos %d = %d, %v, want _, %v", bigtest.encoded, total, n, err, error(nil))
                        total += n
                }
                testEqual(t, "Decoding/%d of %q = %q, want %q", bs, bigtest.encoded, string(buf[0:total]), bigtest.decoded)
        }
}

func TestDecodeCorrupt(t *testing.T) {
        type corrupt struct {
                e string
                p int
        }
        examples := []corrupt{
                {"v", 0},
                {"!z!!!!!!!!!", 1},
        }

        for _, e := range examples {
                dbuf := make([]byte, 4*len(e.e))
                _, _, err := Decode(dbuf, []byte(e.e), true)
                switch err := err.(type) {
                case CorruptInputError:
                        testEqual(t, "Corruption in %q at offset %v, want %v", e.e, int(err), e.p)
                default:
                        t.Error("Decoder failed to detect corruption in", e)
                }
        }
}

func TestBig(t *testing.T) {
        n := 3*1000 + 1
        raw := make([]byte, n)
        const alpha = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
        for i := 0; i < n; i++ {
                raw[i] = alpha[i%len(alpha)]
        }
        encoded := new(bytes.Buffer)
        w := NewEncoder(encoded)
        nn, err := w.Write(raw)
        if nn != n || err != nil {
                t.Fatalf("Encoder.Write(raw) = %d, %v want %d, nil", nn, err, n)
        }
        err = w.Close()
        if err != nil {
                t.Fatalf("Encoder.Close() = %v want nil", err)
        }
        decoded, err := ioutil.ReadAll(NewDecoder(encoded))
        if err != nil {
                t.Fatalf("io.ReadAll(NewDecoder(...)): %v", err)
        }

        if !bytes.Equal(raw, decoded) {
                var i int
                for i = 0; i < len(decoded) && i < len(raw); i++ {
                        if decoded[i] != raw[i] {
                                break
                        }
                }
                t.Errorf("Decode(Encode(%d-byte string)) failed at offset %d", n, i)
        }
}