Increased coverage

ptrie/trie_test.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"testing"
 
+	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/ethutil"
 )
 
@@ -18,6 +19,15 @@ func NewEmpty() *Trie {
 	return New(nil, make(Db))
 }
 
+func TestEmptyTrie(t *testing.T) {
+	trie := NewEmpty()
+	res := trie.Hash()
+	exp := crypto.Sha3(ethutil.Encode(""))
+	if !bytes.Equal(res, exp) {
+		t.Errorf("expected %x got %x", exp, res)
+	}
+}
+
 func TestInsert(t *testing.T) {
 	trie := NewEmpty()
 
@@ -62,6 +72,34 @@ func TestGet(t *testing.T) {
 func TestDelete(t *testing.T) {
 	trie := NewEmpty()
 
+	vals := []struct{ k, v string }{
+		{"do", "verb"},
+		{"ether", "wookiedoo"},
+		{"horse", "stallion"},
+		{"shaman", "horse"},
+		{"doge", "coin"},
+		{"ether", ""},
+		{"dog", "puppy"},
+		{"shaman", ""},
+	}
+	for _, val := range vals {
+		if val.v != "" {
+			trie.UpdateString(val.k, val.v)
+		} else {
+			trie.DeleteString(val.k)
+		}
+	}
+
+	hash := trie.Hash()
+	exp := ethutil.Hex2Bytes("5991bb8c6514148a29db676a14ac506cd2cd5775ace63c30a4fe457715e9ac84")
+	if !bytes.Equal(hash, exp) {
+		t.Errorf("expected %x got %x", exp, hash)
+	}
+}
+
+func TestEmptyValues(t *testing.T) {
+	trie := NewEmpty()
+
 	vals := []struct{ k, v string }{
 		{"do", "verb"},
 		{"ether", "wookiedoo"},
@@ -142,7 +180,7 @@ func TestReset(t *testing.T) {
 	}
 }
 
-// Not actual test
+// Not an actual test
 func TestOutput(t *testing.T) {
 	t.Skip()