func TestPrependedBlocks(t *testing.T) {
const BLOCKSIZE = 100
const BLOCK_COUNT = 20
checksum := NewFileChecksumGenerator(BLOCKSIZE)
file1 := io.LimitReader(
readers.NewNonRepeatingSequence(0),
BLOCKSIZE*BLOCK_COUNT,
)
file2 := io.LimitReader(
io.MultiReader(
readers.OneReader(BLOCKSIZE), // Off by one block
readers.NewNonRepeatingSequence(0),
),
BLOCKSIZE*BLOCK_COUNT,
)
output1 := bytes.NewBuffer(nil)
chksum1, _ := checksum.GenerateChecksums(file1, output1)
output2 := bytes.NewBuffer(nil)
chksum2, _ := checksum.GenerateChecksums(file2, output2)
if bytes.Compare(chksum1, chksum2) == 0 {
t.Fatal("Checksums should be different")
}
weaksize, strongSize := checksum.GetChecksumSizes()
sums1, _ := chunks.LoadChecksumsFromReader(output1, weaksize, strongSize)
sums2, _ := chunks.LoadChecksumsFromReader(output2, weaksize, strongSize)
if len(sums1) != len(sums2) {
t.Fatalf("Checksum lengths differ %v vs %v", len(sums1), len(sums2))
}
if sums1[0].Match(sums2[0]) {
t.Error("Chunk sums1[0] should differ from sums2[0]")
}
for i, _ := range sums2 {
if i == 0 {
continue
}
if !sums1[i-1].Match(sums2[i]) {
t.Errorf("Chunk sums1[%v] equal sums2[%v]", i-1, i)
}
}
}
// Test that partial content that ends in the middle of a strong
// hash is caught correctly
func TestInvalidReaderLength_Strong(t *testing.T) {
const BLOCKSIZE = 100
checksum := NewFileChecksumGenerator(BLOCKSIZE)
file1 := io.LimitReader(
readers.NewNonRepeatingSequence(0),
int64(checksum.ChecksumSize())+int64(checksum.WeakRollingHash.Size())+2,
)
ws, ss := checksum.GetChecksumSizes()
r, err := chunks.LoadChecksumsFromReader(file1, ws, ss)
if r != nil || err != chunks.ErrPartialChecksum {
t.Error("Expected partial checksum error")
}
}