key version check always always relies on the network property

[#27]

src/hdwallet.js

@@ -13,10 +13,9 @@ var HDWallet = module.exports = function(seed, network) {
 
     var I = Crypto.HMAC(Crypto.SHA512, seed, 'Bitcoin seed', { asBytes: true })
     this.chaincode = I.slice(32)
-    this.keyVersion = network == 'Bitcoin' ? Address.address_types.prod : Address.address_types.testnet
-    this.priv = new ECKey(I.slice(0, 32).concat([1]), true, this.keyVersion)
-    this.pub = this.priv.getPub()
     this.network = network || 'Bitcoin'
+    this.priv = new ECKey(I.slice(0, 32).concat([1]), true, this.getKeyVersion())
+    this.pub = this.priv.getPub()
     this.index = 0
     this.depth = 0
 }
@@ -107,10 +106,10 @@ HDWallet.fromBytes = function(input) {
     // 33 bytes: the public key or private key data (0x02 + X or 0x03 + X for
     // public keys, 0x00 + k for private keys)
     if (type == 'private') {
-        hd.priv = new ECKey(input.slice(46, 78).concat([1]), true, this.keyVersion)
+        hd.priv = new ECKey(input.slice(46, 78).concat([1]), true, hd.getKeyVersion())
         hd.pub = hd.priv.getPub()
     } else {
-        hd.pub = new ECPubKey(input.slice(45, 78), true, this.keyVersion)
+        hd.pub = new ECPubKey(input.slice(45, 78), true, hd.getKeyVersion())
     }
 
     return hd
@@ -214,11 +213,11 @@ HDWallet.prototype.derive = function(i) {
         // ki = IL + kpar (mod n).
         hd.priv = this.priv.add(new ECKey(IL.concat([1])))
         hd.priv.compressed = true
-        hd.priv.version = this.keyVersion
+        hd.priv.version = this.getKeyVersion()
         hd.pub = hd.priv.getPub()
     } else {
         // Ki = (IL + kpar)*G = IL*G + Kpar
-        hd.pub = this.pub.add(new ECKey(IL.concat([1]), true, this.keyVersion).getPub())
+        hd.pub = this.pub.add(new ECKey(IL.concat([1]), true, this.getKeyVersion()).getPub())
     }
 
     // ci = IR.
@@ -234,4 +233,8 @@ HDWallet.prototype.derivePrivate = function(index) {
     return this.derive(index + HDWallet.HIGHEST_BIT)
 }
 
+HDWallet.prototype.getKeyVersion = function() {
+    return this.network == 'Bitcoin' ? Address.address_types.prod : Address.address_types.testnet
+}
+
 HDWallet.prototype.toString = HDWallet.prototype.toBase58