mv go-crypto files to crypto dir

crypto/tmhash/hash.go

@@ -0,0 +1,48 @@
+package tmhash
+
+import (
+	"crypto/sha256"
+	"hash"
+)
+
+const (
+	Size      = 20
+	BlockSize = sha256.BlockSize
+)
+
+type sha256trunc struct {
+	sha256 hash.Hash
+}
+
+func (h sha256trunc) Write(p []byte) (n int, err error) {
+	return h.sha256.Write(p)
+}
+func (h sha256trunc) Sum(b []byte) []byte {
+	shasum := h.sha256.Sum(b)
+	return shasum[:Size]
+}
+
+func (h sha256trunc) Reset() {
+	h.sha256.Reset()
+}
+
+func (h sha256trunc) Size() int {
+	return Size
+}
+
+func (h sha256trunc) BlockSize() int {
+	return h.sha256.BlockSize()
+}
+
+// New returns a new hash.Hash.
+func New() hash.Hash {
+	return sha256trunc{
+		sha256: sha256.New(),
+	}
+}
+
+// Sum returns the first 20 bytes of SHA256 of the bz.
+func Sum(bz []byte) []byte {
+	hash := sha256.Sum256(bz)
+	return hash[:Size]
+}

crypto/tmhash/hash_test.go

@@ -0,0 +1,23 @@
+package tmhash_test
+
+import (
+	"crypto/sha256"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/tendermint/go-crypto/tmhash"
+)
+
+func TestHash(t *testing.T) {
+	testVector := []byte("abc")
+	hasher := tmhash.New()
+	hasher.Write(testVector)
+	bz := hasher.Sum(nil)
+
+	hasher = sha256.New()
+	hasher.Write(testVector)
+	bz2 := hasher.Sum(nil)
+	bz2 = bz2[:20]
+
+	assert.Equal(t, bz, bz2)
+}