Merge pull request #222 from jbenet/fix/peer-string-2014-10-28

fix(peer) String() bounds check

peer/peer.go

@@ -115,8 +115,18 @@ type peer struct {
 }
 
 // String prints out the peer.
+//
+// TODO(brian): ensure correctness at ID generation and
+// enforce this by only exposing functions that generate
+// IDs safely. Then any peer.ID type found in the
+// codebase is known to be correct.
 func (p *peer) String() string {
-	return "[Peer " + p.id.String()[:12] + "]"
+	pid := p.id.String()
+	maxRunes := 12
+	if len(pid) < maxRunes {
+		maxRunes = len(pid)
+	}
+	return "[Peer " + pid[:maxRunes] + "]"
 }
 
 // Key returns the ID as a Key (string) for maps.

peer/peer_test.go

@@ -46,3 +46,12 @@ func TestNetAddress(t *testing.T) {
 		t.Error("NetAddress lookup failed", udp, udp2)
 	}
 }
+
+func TestStringMethodWithSmallId(t *testing.T) {
+	p := WithID([]byte(string(0)))
+	p1, ok := p.(*peer)
+	if !ok {
+		t.Fatal("WithID doesn't return a peer")
+	}
+	p1.String()
+}