Export VarIntSerializeSize function.

This commit exports the VarIntSerializeSize function to provide callers
with an easy method to determine how many bytes it would take to serialize
the passed value as a variable length integer.

common.go

@@ -325,9 +325,9 @@ func writeVarInt(w io.Writer, pver uint32, val uint64) error {
 	return err
 }
 
-// varIntSerializeSize returns the number of bytes it would take to serialize
+// VarIntSerializeSize returns the number of bytes it would take to serialize
 // val as a variable length integer.
-func varIntSerializeSize(val uint64) int {
+func VarIntSerializeSize(val uint64) int {
 	// The value is small enough to be represented by itself, so it's
 	// just 1 byte.
 	if val < 0xfd {

common_test.go

@@ -352,9 +352,9 @@ func TestVarIntSerializeSize(t *testing.T) {
 
 	t.Logf("Running %d tests", len(tests))
 	for i, test := range tests {
-		serializedSize := btcwire.TstVarIntSerializeSize(test.val)
+		serializedSize := btcwire.VarIntSerializeSize(test.val)
 		if serializedSize != test.size {
-			t.Errorf("varIntSerializeSize #%d got: %d, want: %d", i,
+			t.Errorf("VarIntSerializeSize #%d got: %d, want: %d", i,
 				serializedSize, test.size)
 			continue
 		}

internal_test.go

@@ -53,12 +53,6 @@ func TstWriteVarInt(w io.Writer, pver uint32, val uint64) error {
 	return writeVarInt(w, pver, val)
 }
 
-// TstVarIntSerializeSize makes the internal varIntSerializeSize function
-// available to the test package.
-func TstVarIntSerializeSize(val uint64) int {
-	return varIntSerializeSize(val)
-}
-
 // TstReadVarString makes the internal readVarString function available to the
 // test package.
 func TstReadVarString(r io.Reader, pver uint32) (string, error) {

msgtx.go

@@ -88,7 +88,7 @@ func (t *TxIn) SerializeSize() int {
 	// Outpoint Hash 32 bytes + Outpoint Index 4 bytes + Sequence 4 bytes +
 	// serialized varint size for the length of SignatureScript +
 	// SignatureScript bytes.
-	return 40 + varIntSerializeSize(uint64(len(t.SignatureScript))) +
+	return 40 + VarIntSerializeSize(uint64(len(t.SignatureScript))) +
 		len(t.SignatureScript)
 }
 
@@ -114,7 +114,7 @@ type TxOut struct {
 func (t *TxOut) SerializeSize() int {
 	// Value 8 bytes + serialized varint size for the length of PkScript +
 	// PkScript bytes.
-	return 8 + varIntSerializeSize(uint64(len(t.PkScript))) + len(t.PkScript)
+	return 8 + VarIntSerializeSize(uint64(len(t.PkScript))) + len(t.PkScript)
 }
 
 // NewTxOut returns a new bitcoin transaction output with the provided
@@ -388,8 +388,8 @@ func (msg *MsgTx) Serialize(w io.Writer) error {
 func (msg *MsgTx) SerializeSize() int {
 	// Version 4 bytes + LockTime 4 bytes + Serialized varint size for the
 	// number of transaction inputs and outputs.
-	n := 8 + varIntSerializeSize(uint64(len(msg.TxIn))) +
-		varIntSerializeSize(uint64(len(msg.TxOut)))
+	n := 8 + VarIntSerializeSize(uint64(len(msg.TxIn))) +
+		VarIntSerializeSize(uint64(len(msg.TxOut)))
 
 	for _, txIn := range msg.TxIn {
 		n += txIn.SerializeSize()