From ed7d4b3b12e9ccc01b559f9e1b82d3b31f6fe668 Mon Sep 17 00:00:00 2001
From: Jeromy <why@ipfs.io>
Date: Mon, 24 Oct 2016 15:31:20 -0700
Subject: [PATCH] guard against empty strings

---
 multibase.go      | 4 ++++
 multibase_test.go | 5 +++++
 2 files changed, 9 insertions(+)

diff --git a/multibase.go b/multibase.go
index 8f1ce04..20d254c 100644
--- a/multibase.go
+++ b/multibase.go
@@ -31,6 +31,10 @@ func Encode(base int, data []byte) (string, error) {
 }
 
 func Decode(data string) (int, []byte, error) {
+	if len(data) == 0 {
+		return 0, nil, fmt.Errorf("cannot decode multibase for zero length string")
+	}
+
 	switch data[0] {
 	case Base58BTC:
 		return Base58BTC, b58.DecodeAlphabet(data[1:], b58.BTCAlphabet), nil
diff --git a/multibase_test.go b/multibase_test.go
index 5bb001e..8b8b6f1 100644
--- a/multibase_test.go
+++ b/multibase_test.go
@@ -27,4 +27,9 @@ func TestBase58RoundTrip(t *testing.T) {
 	if !bytes.Equal(buf, out) {
 		t.Fatal("input wasnt the same as output", buf, out)
 	}
+
+	_, _, err = Decode("")
+	if err == nil {
+		t.Fatal("shouldnt be able to decode empty string")
+	}
 }