protocol/rtp: wrote TestVersion

Wrote test that checks the version func will correctly get the
version from an RTP packet.

protocol/rtp/parse.go

@@ -84,5 +84,5 @@ func csrcCount(d []byte) int {
 
 // version returns the version of the RTP packet.
 func version(d []byte) int {
-	return int(d[0] & 0xb0 >> 4)
+	return int(d[0] & 0xc0 >> 6)
 }

protocol/rtp/parse_test.go

@@ -26,3 +26,17 @@ LICENSE
 */
 
 package rtp
+
+import (
+	"testing"
+)
+
+// TestVersion checks that we can correctly get the version from an RTP packet.
+func TestVersion(t *testing.T) {
+	const expect = 1
+	pkt := (&Pkt{V: expect}).Bytes(nil)
+	got := version(pkt)
+	if got != expect {
+		t.Errorf("unexpected version for RTP packet. Got: %v\n Want: %v\n", got, expect)
+	}
+}