path: root/swarm/multihash/multihash_test.go

// Copyright 2018 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.

package multihash

import (
    "bytes"
    "math/rand"
    "testing"
)

// parse multihash, and check that invalid multihashes fail
func TestCheckMultihash(t *testing.T) {
    hashbytes := make([]byte, 32)
    c, err := rand.Read(hashbytes)
    if err != nil {
        t.Fatal(err)
    } else if c < 32 {
        t.Fatal("short read")
    }

    expected := ToMultihash(hashbytes)

    l, hl, _ := GetMultihashLength(expected)
    if l != 32 {
        t.Fatalf("expected length %d, got %d", 32, l)
    } else if hl != 2 {
        t.Fatalf("expected header length %d, got %d", 2, hl)
    }
    if _, _, err := GetMultihashLength(expected[1:]); err == nil {
        t.Fatal("expected failure on corrupt header")
    }
    if _, _, err := GetMultihashLength(expected[:len(expected)-2]); err == nil {
        t.Fatal("expected failure on short content")
    }
    dh, _ := FromMultihash(expected)
    if !bytes.Equal(dh, hashbytes) {
        t.Fatalf("expected content hash %x, got %x", hashbytes, dh)
    }
}