Merge pull request #200 from dcousens/walletclean

HD/Wallet clean

src/bufferutils.js

@@ -1,6 +1,14 @@
 var assert = require('assert')
 var opcodes = require('./opcodes')
 
+// https://github.com/feross/buffer/blob/master/index.js#L1127
+function verifuint(value, max) {
+  assert(typeof value === 'number', 'cannot write a non-number as a number')
+  assert(value >= 0, 'specified a negative value for writing an unsigned value')
+  assert(value <= max, 'value is larger than maximum value for type')
+  assert(Math.floor(value) === value, 'value has a fractional component')
+}
+
 function pushDataSize(i) {
   return i < opcodes.OP_PUSHDATA1 ? 1
     : i < 0xff        ? 2
@@ -47,9 +55,7 @@ function readUInt64LE(buffer, offset) {
   var b = buffer.readUInt32LE(offset + 4)
   b *= 0x100000000
 
-  // Javascript Safe Integer limitation
-  // assert(Number.isSafeInteger(value), 'value must be < 2^53')
-  assert(b + a < 0x0020000000000000, 'value must be < 2^53')
+  verifuint(b + a, 0x001fffffffffffff)
 
   return b + a
 }
@@ -104,10 +110,6 @@ function writePushDataInt(buffer, number, offset) {
 
   // 32 bit
   } else {
-    // Javascript Safe Integer limitation
-    // assert(Number.isSafeInteger(value), 'value must be < 2^53')
-    assert(number < 0x0020000000000000, 'value must be < 2^53')
-
     buffer.writeUInt8(opcodes.OP_PUSHDATA4, offset)
     buffer.writeUInt32LE(number, offset + 1)
 
@@ -117,9 +119,7 @@ function writePushDataInt(buffer, number, offset) {
 }
 
 function writeUInt64LE(buffer, value, offset) {
-  // Javascript Safe Integer limitation
-  // assert(Number.isSafeInteger(value), 'value must be < 2^53')
-  assert(value < 0x0020000000000000, 'value must be < 2^53')
+  verifuint(value, 0x001fffffffffffff)
 
   buffer.writeInt32LE(value & -1, offset)
   buffer.writeUInt32LE(Math.floor(value / 0x100000000), offset + 4)

src/hdwallet.js

@@ -12,14 +12,11 @@ var networks = require('./networks')
 var sec = require('./sec')
 var ecparams = sec("secp256k1")
 
-function HDWallet(seed, networkString) {
+function HDWallet(seed, network) {
   if (seed == undefined) return; // FIXME: Boo, should be stricter
 
-  this.network = networkString || 'bitcoin'
-
-  if(!networks.hasOwnProperty(this.network)) {
-    throw new Error("Unknown network: " + this.network)
-  }
+  network = network || networks.bitcoin
+  assert(network.bip32, 'Unknown BIP32 constants for network')
 
   var I = crypto.HmacSHA512(seed, HDWallet.MASTER_SECRET)
   var IL = I.slice(0, 32)
@@ -28,6 +25,7 @@ function HDWallet(seed, networkString) {
   // In case IL is 0 or >= n, the master key is invalid (handled by ECKey.fromBuffer)
   var pIL = BigInteger.fromBuffer(IL)
 
+  this.network = network
   this.priv = new ECKey(pIL, true)
   this.pub = this.priv.pub
 
@@ -40,8 +38,8 @@ HDWallet.MASTER_SECRET = new Buffer('Bitcoin seed')
 HDWallet.HIGHEST_BIT = 0x80000000
 HDWallet.LENGTH = 78
 
-HDWallet.fromSeedHex = function(hex, networkString) {
-  return new HDWallet(new Buffer(hex, 'hex'), networkString)
+HDWallet.fromSeedHex = function(hex, network) {
+  return new HDWallet(new Buffer(hex, 'hex'), network)
 }
 
 HDWallet.fromBase58 = function(string) {
@@ -51,8 +49,8 @@ HDWallet.fromBase58 = function(string) {
   var checksum = buffer.slice(-4)
   var newChecksum = crypto.hash256(payload).slice(0, 4)
 
-  assert.deepEqual(newChecksum, checksum)
-  assert.equal(payload.length, HDWallet.LENGTH)
+  assert.deepEqual(newChecksum, checksum, 'Invalid checksum')
+  assert.equal(payload.length, HDWallet.LENGTH, 'Invalid BIP32 string')
 
   return HDWallet.fromBuffer(payload)
 }
@@ -66,14 +64,14 @@ HDWallet.fromBuffer = function(input) {
   var version = input.readUInt32BE(0)
 
   var type
-  for(var name in networks) {
+  for (var name in networks) {
     var network = networks[name]
 
-    for(var t in network.bip32) {
+    for (var t in network.bip32) {
       if (version != network.bip32[t]) continue
 
       type = t
-      hd.network = name
+      hd.network = network
     }
   }
 
@@ -127,7 +125,7 @@ HDWallet.prototype.getAddress = function() {
 
 HDWallet.prototype.toBuffer = function(priv) {
   // Version
-  var version = networks[this.network].bip32[priv ? 'priv' : 'pub']
+  var version = this.network.bip32[priv ? 'priv' : 'pub']
   var buffer = new Buffer(HDWallet.LENGTH)
 
   // 4 bytes: version bytes
@@ -254,7 +252,7 @@ HDWallet.prototype.derivePrivate = function(index) {
 }
 
 HDWallet.prototype.getKeyVersion = function() {
-  return networks[this.network].pubKeyHash
+  return this.network.pubKeyHash
 }
 
 HDWallet.prototype.toString = HDWallet.prototype.toBase58

src/wallet.js

@@ -1,15 +1,13 @@
-var Address = require('./address')
-var convert = require('./convert')
-var HDNode = require('./hdwallet.js')
+var assert = require('assert')
 var networks = require('./networks')
 var rng = require('secure-random')
-var Transaction = require('./transaction').Transaction
 
-function Wallet(seed, options) {
-  if (!(this instanceof Wallet)) { return new Wallet(seed, options); }
+var Address = require('./address')
+var HDNode = require('./hdwallet')
+var Transaction = require('./transaction').Transaction
 
-  var options = options || {}
-  var network = options.network || 'bitcoin'
+function Wallet(seed, network) {
+  network = network || networks.bitcoin
 
   // Stored in a closure to make accidental serialization less likely
   var masterkey = null
@@ -22,11 +20,14 @@ function Wallet(seed, options) {
   this.addresses = []
   this.changeAddresses = []
 
+  // Dust value
+  this.dustThreshold = 5430
+
   // Transaction output data
   this.outputs = {}
 
   // Make a new master key
-  this.newMasterKey = function(seed, network) {
+  this.newMasterKey = function(seed) {
     seed = seed || new Buffer(rng(32))
     masterkey = new HDNode(seed, network)
 
@@ -41,7 +42,8 @@ function Wallet(seed, options) {
 
     me.outputs = {}
   }
-  this.newMasterKey(seed, network)
+
+  this.newMasterKey(seed)
 
   this.generateAddress = function() {
     var key = externalAccount.derive(this.addresses.length)
@@ -84,23 +86,11 @@ function Wallet(seed, options) {
     this.outputs = outputs
   }
 
-  this.setUnspentOutputsAsync = function(utxo, callback) {
-    var error = null
-    try {
-      this.setUnspentOutputs(utxo)
-    } catch(err) {
-      error = err
-    } finally {
-      process.nextTick(function(){ callback(error) })
-    }
-  }
-
   function outputToUnspentOutput(output){
     var hashAndIndex = output.receive.split(":")
 
     return {
       hash: hashAndIndex[0],
-      hashLittleEndian: convert.reverseEndian(hashAndIndex[0]),
       outputIndex: parseInt(hashAndIndex[1]),
       address: output.address,
       value: output.value
@@ -108,7 +98,7 @@ function Wallet(seed, options) {
   }
 
   function unspentOutputToOutput(o) {
-    var hash = o.hash || convert.reverseEndian(o.hashLittleEndian)
+    var hash = o.hash
     var key = hash + ":" + o.outputIndex
     return {
       receive: key,
@@ -120,8 +110,8 @@ function Wallet(seed, options) {
   function validateUnspentOutput(uo) {
     var missingField
 
-    if (isNullOrUndefined(uo.hash) && isNullOrUndefined(uo.hashLittleEndian)) {
-      missingField = "hash(or hashLittleEndian)"
+    if (isNullOrUndefined(uo.hash)) {
+      missingField = "hash"
     }
 
     var requiredKeys = ['outputIndex', 'address', 'value']
@@ -137,7 +127,7 @@ function Wallet(seed, options) {
         'A valid unspent output must contain'
       ]
       message.push(requiredKeys.join(', '))
-      message.push("and hash(or hashLittleEndian)")
+      message.push("and hash")
       throw new Error(message.join(' '))
     }
   }
@@ -153,7 +143,7 @@ function Wallet(seed, options) {
       var address
 
       try {
-        address = Address.fromScriptPubKey(txOut.script, networks[network]).toString()
+        address = Address.fromScriptPubKey(txOut.script, network).toString()
       } catch(e) {
         if (!(e.message.match(/has no matching Address/))) throw e
       }
@@ -171,73 +161,50 @@ function Wallet(seed, options) {
 
     tx.ins.forEach(function(txIn, i){
       var op = txIn.outpoint
-      var o = me.outputs[op.hash+':'+op.index]
+
+      var o = me.outputs[op.hash + ':' + op.index]
       if (o) {
-        o.spend = txhash + ':' +i
+        o.spend = txhash + ':' + i
       }
     })
   }
 
   this.createTx = function(to, value, fixedFee, changeAddress) {
-    checkDust(value)
+    assert(value > this.dustThreshold, value + ' must be above dust threshold (' + this.dustThreshold + ' Satoshis)')
+
+    var utxos = getCandidateOutputs(value)
+    var accum = 0
+    var subTotal = value
 
     var tx = new Transaction()
     tx.addOutput(to, value)
 
-    var utxo = getCandidateOutputs(value)
-    var totalInValue = 0
-    for(var i=0; i<utxo.length; i++){
-      var output = utxo[i]
-      tx.addInput(output.receive)
+    for (var i = 0; i < utxos.length; ++i) {
+      var utxo = utxos[i]
 
-      totalInValue += output.value
-      if(totalInValue < value) continue
+      tx.addInput(utxo.receive)
+      accum += utxo.value
 
       var fee = fixedFee == undefined ? estimateFeePadChangeOutput(tx) : fixedFee
-      if(totalInValue < value + fee) continue
 
-      var change = totalInValue - value - fee
-      if(change > 0 && !isDust(change)) {
-        tx.addOutput(changeAddress || getChangeAddress(), change)
+      subTotal = value + fee
+      if (accum >= subTotal) {
+        var change = accum - subTotal
+
+        if (change > this.dustThreshold) {
+          tx.addOutput(changeAddress || getChangeAddress(), change)
+        }
+
+        break
       }
-      break
     }
 
-    checkInsufficientFund(totalInValue, value, fee)
+    assert(accum >= subTotal, 'Not enough funds (incl. fee): ' + accum + ' < ' + subTotal)
 
     this.sign(tx)
-
     return tx
   }
 
-  this.createTxAsync = function(to, value, fixedFee, callback){
-    if(fixedFee instanceof Function) {
-      callback = fixedFee
-      fixedFee = undefined
-    }
-    var tx = null
-    var error = null
-
-    try {
-      tx = this.createTx(to, value, fixedFee)
-    } catch(err) {
-      error = err
-    } finally {
-      process.nextTick(function(){ callback(error, tx) })
-    }
-  }
-
-  this.dustThreshold = 5430
-  function isDust(amount) {
-    return amount <= me.dustThreshold
-  }
-
-  function checkDust(value){
-    if (isNullOrUndefined(value) || isDust(value)) {
-      throw new Error("Value must be above dust threshold")
-    }
-  }
-
   function getCandidateOutputs(value){
     var unspent = []
     for (var key in me.outputs){
@@ -263,13 +230,6 @@ function Wallet(seed, options) {
     return me.changeAddresses[me.changeAddresses.length - 1]
   }
 
-  function checkInsufficientFund(totalInValue, value, fee) {
-    if(totalInValue < value + fee) {
-      throw new Error('Not enough money to send funds including transaction fee. Have: ' +
-                      totalInValue + ', needed: ' + (value + fee))
-    }
-  }
-
   this.sign = function(tx) {
     tx.ins.forEach(function(inp,i) {
       var output = me.outputs[inp.outpoint.hash + ':' + inp.outpoint.index]

test/bufferutils.js

@@ -1,7 +1,7 @@
 var assert = require('assert')
 var bufferutils = require('../src/bufferutils')
 
-var fixtures = require('./fixtures/buffer.json')
+var fixtures = require('./fixtures/bufferutils.json')
 
 describe('bufferutils', function() {
   describe('pushDataSize', function() {
@@ -39,6 +39,16 @@ describe('bufferutils', function() {
         assert.equal(number, f.dec)
       })
     })
+
+    fixtures.invalid.forEach(function(f) {
+      it('throws on ' + f.description, function() {
+        var buffer = new Buffer(f.hex64, 'hex')
+
+        assert.throws(function() {
+          bufferutils.readUInt64LE(buffer, 0)
+        }, new RegExp(f.exception))
+      })
+    })
   })
 
   describe('readVarInt', function() {
@@ -51,6 +61,16 @@ describe('bufferutils', function() {
         assert.equal(d.size, buffer.length)
       })
     })
+
+    fixtures.invalid.forEach(function(f) {
+      it('throws on ' + f.description, function() {
+        var buffer = new Buffer(f.hexVI, 'hex')
+
+        assert.throws(function() {
+          bufferutils.readVarInt(buffer, 0)
+        }, new RegExp(f.exception))
+      })
+    })
   })
 
   describe('varIntSize', function() {
@@ -75,17 +95,6 @@ describe('bufferutils', function() {
         assert.equal(buffer.slice(0, n).toString('hex'), f.hexPD)
       })
     })
-
-    fixtures.invalid.forEach(function(f) {
-      it('throws on ' + f.description, function() {
-        var buffer = new Buffer(5)
-        buffer.fill(0)
-
-        assert.throws(function() {
-          bufferutils.writePushDataInt(buffer, f.dec, 0)
-        }, /value must be < 2\^53/)
-      })
-    })
   })
 
   describe('writeUInt64LE', function() {
@@ -106,7 +115,7 @@ describe('bufferutils', function() {
 
         assert.throws(function() {
           bufferutils.writeUInt64LE(buffer, f.dec, 0)
-        }, /value must be < 2\^53/)
+        }, new RegExp(f.exception))
       })
     })
   })
@@ -129,7 +138,7 @@ describe('bufferutils', function() {
 
         assert.throws(function() {
           bufferutils.writeVarInt(buffer, f.dec, 0)
-        }, /value must be < 2\^53/)
+        }, new RegExp(f.exception))
       })
     })
   })

test/fixtures/buffer.json → test/fixtures/bufferutils.json

@@ -85,11 +85,17 @@
   "invalid": [
     {
       "description": "n === 2^53",
-      "value": 9007199254740992
+      "exception": "value is larger than maximum value for type",
+      "hex64": "0000000000002000",
+      "hexVI": "ff0000000000000020",
+      "dec": 9007199254740992
     },
     {
       "description": "n > 2^53",
-      "value": 18374686479671624000
+      "exception": "value is larger than maximum value for type",
+      "hex64": "0100000000002000",
+      "hexVI": "ff0100000000000020",
+      "dec": 9007199254740993
     }
   ]
 }

test/fixtures/hdwallet.json

@@ -176,5 +176,20 @@
       ]
     }
   ],
-  "invalid": []
+  "invalid": {
+    "fromBase58": [
+      {
+        "exception": "Invalid checksum",
+        "string": "xprvQQQQQQQQQQQQQQQQCviVfJSKyQ1mDYahRjijr5idH2WwLsEd4Hsb2Tyh8RfQMuPh7f7RtyzTtdrbdqqsunu5Mm3wDvUAKRHSC34sJ7in334"
+      },
+      {
+        "exception": "Invalid BIP32 string",
+        "string": "SQ8nQ2jWarXqLo9oHGKKP6iQDsQbPRftq7rjtYY3hqJRPQRgrmeunFnDKbH7B15yGPLZBrhhkKXx3pwD6LcBooJRGq6x7matAXpMsgn"
+      },
+      {
+        "exception": "Invalid BIP32 string",
+        "string": "37hdAfw3aMiWcBGPP2ywmY5jizTeSSP5GXayKY3RxkEZ7f3SBnRE1pN6eY3VzGkgx6vbdNtuKfrHgEaYvW9KkFZCycaPvWiA9TtfmeVB592Sf9RfSzQzXo72"
+      }
+    ]
+  }
 }

test/hdwallet.js

@@ -1,4 +1,5 @@
 var assert = require('assert')
+var networks = require('../src/networks')
 
 var HDWallet = require('../src/hdwallet')
 var fixtures = require('./fixtures/hdwallet.json')
@@ -32,6 +33,16 @@ describe('HDWallet', function() {
     })
   })
 
+  describe('fromBase58', function() {
+    fixtures.invalid.fromBase58.forEach(function(f) {
+      it('throws on ' + f.string, function() {
+        assert.throws(function() {
+          HDWallet.fromBase58(f.string)
+        }, new RegExp(f.exception))
+      })
+    })
+  })
+
   describe('constructor & seed deserialization', function() {
     var expectedPrivateKey = '0fd71c652e847ba7ea7956e3cf3fc0a0985871846b1b2c23b9c6a29a38cee860'
     var seed = new Buffer([
@@ -68,6 +79,15 @@ describe('HDWallet', function() {
         buffer.writeUInt32BE(0xFFFFFFFF, 9)
         assert.throws(function() { HDWallet.fromBuffer(buffer) }, /Invalid index/)
       })
+
+      it('fails for an invalid network type', function() {
+        var network = { bip32: { priv: 0x11111111, pub: 0x22222222 } }
+        var buffer = new HDWallet(seed, network).toBuffer()
+
+        assert.throws(function() {
+          HDWallet.fromBuffer(buffer)
+        }, /Could not find version 22222222/)
+      })
     })
   })
 
@@ -119,24 +139,36 @@ describe('HDWallet', function() {
   })
 
   describe('network types', function() {
+    var seed
+
+    beforeEach(function() {
+      seed = new Buffer('foobar')
+    })
+
+    it('ensure that a bitcoin wallet is the default', function() {
+      var wallet = new HDWallet(seed)
+
+      assert.equal(wallet.network, networks.bitcoin)
+    })
+
     it('ensures that a bitcoin Wallet generates bitcoin addresses', function() {
-      var wallet = new HDWallet(new Buffer('foobar'), 'bitcoin')
-      assert.equal(wallet.getAddress().toString(), '17SnB9hyGwJPoKpLb9eVPHjsujyEuBpMAA')
+      var wallet = new HDWallet(seed)
+      var address = wallet.getAddress().toString()
+
+      assert.equal(address, '17SnB9hyGwJPoKpLb9eVPHjsujyEuBpMAA')
     })
 
     it('ensures that a testnet Wallet generates testnet addresses', function() {
-      var wallet = new HDWallet(new Buffer('foobar'), 'testnet')
-      assert.equal(wallet.getAddress().toString(), 'mmxjUCnx5xjeaSHxJicsDCxCmjZwq8KTbv')
-    })
+      var wallet = new HDWallet(seed, networks.testnet)
+      var address = wallet.getAddress().toString()
 
-    it('throws an exception when unknown network type is passed in', function() {
-      assert.throws(function() { new HDWallet(new Buffer('foobar'), 'doge') }, /Unknown network: doge/)
+      assert.equal(address, 'mmxjUCnx5xjeaSHxJicsDCxCmjZwq8KTbv')
     })
 
-    it('throws an exception with bad network type using fromBuffer', function() {
-      var buffer = new HDWallet(new Buffer('foobar'), 'bitcoin').toBuffer()
-      buffer.writeUInt32BE(0x00000000, 0)
-      assert.throws(function() { HDWallet.fromBuffer(buffer) }, /Could not find version 0/)
+    it('throws an exception when unknown network type is passed in', function() {
+      assert.throws(function() {
+        new HDWallet(seed, {})
+      }, /Unknown BIP32 constants for network/)
     })
   })
 })

test/wallet.js

@@ -1,5 +1,6 @@
 var assert = require('assert')
 var crypto = require('../src/crypto')
+var networks = require('../src/networks')
 var sinon = require('sinon')
 
 var Address = require('../src/address')
@@ -24,12 +25,8 @@ describe('Wallet', function() {
   })
 
   describe('constructor', function() {
-    it('should be ok to call without new', function() {
-      assert.ok(Wallet(seed) instanceof Wallet)
-    })
-
     it('defaults to Bitcoin network', function() {
-      assert.equal(wallet.getMasterKey().network, 'bitcoin')
+      assert.equal(wallet.getMasterKey().network, networks.bitcoin)
     })
 
     it("generates m/0' as the main account", function() {
@@ -59,11 +56,11 @@ describe('Wallet', function() {
 
     describe('constructor options', function() {
       beforeEach(function() {
-        wallet = new Wallet(seed, {network: 'testnet'})
+        wallet = new Wallet(seed, networks.testnet)
       })
 
       it('uses the network if specified', function() {
-        assert.equal(wallet.getMasterKey().network, 'testnet')
+        assert.equal(wallet.getMasterKey().network, networks.testnet)
       })
     })
   })
@@ -98,7 +95,7 @@ describe('Wallet', function() {
 
   describe('generateAddress', function(){
     it('generate receiving addresses', function(){
-      var wallet = new Wallet(seed, {network: 'testnet'})
+      var wallet = new Wallet(seed, networks.testnet)
       var expectedAddresses = [
         "n1GyUANZand9Kw6hGSV9837cCC9FFUQzQa",
         "n2fiWrHqD6GM5GiEqkbWAc6aaZQp3ba93X"
@@ -112,7 +109,7 @@ describe('Wallet', function() {
 
   describe('generateChangeAddress', function(){
     it('generates change addresses', function(){
-      var wallet = new Wallet(seed, {network: 'testnet'})
+      var wallet = new Wallet(seed, networks.testnet)
       var expectedAddresses = ["mnXiDR4MKsFxcKJEZjx4353oXvo55iuptn"]
 
       assert.equal(wallet.generateChangeAddress(), expectedAddresses[0])
@@ -122,7 +119,7 @@ describe('Wallet', function() {
 
   describe('getPrivateKey', function(){
     it('returns the private key at the given index of external account', function(){
-      var wallet = new Wallet(seed, {network: 'testnet'})
+      var wallet = new Wallet(seed, networks.testnet)
 
       assertEqual(wallet.getPrivateKey(0), wallet.getExternalAccount().derive(0).priv)
       assertEqual(wallet.getPrivateKey(1), wallet.getExternalAccount().derive(1).priv)
@@ -131,7 +128,7 @@ describe('Wallet', function() {
 
   describe('getInternalPrivateKey', function(){
     it('returns the private key at the given index of internal account', function(){
-      var wallet = new Wallet(seed, {network: 'testnet'})
+      var wallet = new Wallet(seed, networks.testnet)
 
       assertEqual(wallet.getInternalPrivateKey(0), wallet.getInternalAccount().derive(0).priv)
       assertEqual(wallet.getInternalPrivateKey(1), wallet.getInternalAccount().derive(1).priv)
@@ -140,7 +137,7 @@ describe('Wallet', function() {
 
   describe('getPrivateKeyForAddress', function(){
     it('returns the private key for the given address', function(){
-      var wallet = new Wallet(seed, {network: 'testnet'})
+      var wallet = new Wallet(seed, networks.testnet)
       wallet.generateChangeAddress()
       wallet.generateAddress()
       wallet.generateAddress()
@@ -156,7 +153,7 @@ describe('Wallet', function() {
     })
 
     it('raises an error when address is not found', function(){
-      var wallet = new Wallet(seed, {network: 'testnet'})
+      var wallet = new Wallet(seed, networks.testnet)
       assert.throws(function() {
         wallet.getPrivateKeyForAddress("n2fiWrHqD6GM5GiEqkbWAc6aaZQp3ba93X")
       }, /Unknown address. Make sure the address is from the keychain and has been generated./)
@@ -168,7 +165,6 @@ describe('Wallet', function() {
     beforeEach(function(){
       expectedUtxo = {
         "hash":"6a4062273ac4f9ea4ffca52d9fd102b08f6c32faa0a4d1318e3a7b2e437bb9c7",
-        "hashLittleEndian":"c7b97b432e7b3a8e31d1a4a0fa326c8fb002d19f2da5fc4feaf9c43a2762406a",
         "outputIndex": 0,
         "address" : "1AZpKpcfCzKDUeTFBQUL4MokQai3m3HMXv",
         "value": 20000
@@ -230,36 +226,13 @@ describe('Wallet', function() {
         utxo = cloneObject([expectedUtxo])
       })
 
-      it('uses hashLittleEndian when hash is not present', function(){
-        delete utxo[0]['hash']
-
-        wallet.setUnspentOutputs(utxo)
-        verifyOutputs()
-      })
-
-      it('uses hash when hashLittleEndian is not present', function(){
-        delete utxo[0]['hashLittleEndian']
-
-        wallet.setUnspentOutputs(utxo)
-        verifyOutputs()
-      })
-
-      it('uses hash when both hash and hashLittleEndian are present', function(){
+      it('matches the expected behaviour', function(){
         wallet.setUnspentOutputs(utxo)
         verifyOutputs()
       })
 
       describe('required fields', function(){
-        it("throws an error when hash and hashLittleEndian are both missing", function(){
-          delete utxo[0]['hash']
-          delete utxo[0]['hashLittleEndian']
-
-          assert.throws(function() {
-            wallet.setUnspentOutputs(utxo)
-          }, /Invalid unspent output: key hash\(or hashLittleEndian\) is missing/)
-        });
-
-        ['outputIndex', 'address', 'value'].forEach(function(field){
+        ['outputIndex', 'address', 'hash', 'value'].forEach(function(field){
           it("throws an error when " + field + " is missing", function(){
             delete utxo[0][field]
 
@@ -277,38 +250,6 @@ describe('Wallet', function() {
         assert.equal(output.address, utxo[0].address)
       }
     })
-
-    describe('setUnspentOutputsAsync', function(){
-      var utxo
-      beforeEach(function(){
-        utxo = cloneObject([expectedUtxo])
-      })
-
-      afterEach(function(){
-        wallet.setUnspentOutputs.restore()
-      })
-
-      it('calls setUnspentOutputs', function(done){
-        sinon.stub(wallet, "setUnspentOutputs")
-
-        var callback = function(){
-          assert(wallet.setUnspentOutputs.calledWith(utxo))
-          done()
-        }
-
-        wallet.setUnspentOutputsAsync(utxo, callback)
-      })
-
-      it('when setUnspentOutputs throws an error, it invokes callback with error', function(done){
-        sinon.stub(wallet, "setUnspentOutputs").throws()
-
-        var callback = function(err){
-          assert(err instanceof Error)
-          done()
-        }
-        wallet.setUnspentOutputsAsync(utxo, callback)
-      })
-    })
   })
 
   describe('processTx', function(){
@@ -490,21 +431,31 @@ describe('Wallet', function() {
       })
     })
 
-    describe('testnet', function(){
+    describe(networks.testnet, function(){
       it('should create transaction', function(){
+        var wallet = new Wallet(seed, networks.testnet)
+        var address = wallet.generateAddress()
+
+        wallet.setUnspentOutputs([{
+          hash: fakeTxHash(0),
+          outputIndex: 0,
+          address: address,
+          value: value
+        }])
+
         var to = 'mt7MyTVVEWnbwpF5hBn6fgnJcv95Syk2ue'
-        var wallet = new Wallet(seed, {network: 'testnet'})
-        var tx = wallet.createTx(to, value)
+        var toValue = value - 20000
 
+        var tx = wallet.createTx(to, toValue)
         assert.equal(tx.outs.length, 1)
         assert.equal(tx.outs[0].address.toString(), to)
-        assert.equal(tx.outs[0].value, value)
+        assert.equal(tx.outs[0].value, toValue)
       })
     })
 
     describe('changeAddress', function(){
       it('should allow custom changeAddress', function(){
-        var wallet = new Wallet(seed, {network: 'testnet'})
+        var wallet = new Wallet(seed, networks.testnet)
         var address = wallet.generateAddress()
 
         wallet.setUnspentOutputs([{
@@ -595,7 +546,7 @@ describe('Wallet', function() {
 
         assert.throws(function() {
           wallet.createTx(to, value)
-        }, /Value must be above dust threshold/)
+        }, /5430 must be above dust threshold \(5430 Satoshis\)/)
       })
     })
 
@@ -605,62 +556,11 @@ describe('Wallet', function() {
 
         assert.throws(function() {
           wallet.createTx(to, value)
-        }, /Not enough money to send funds including transaction fee. Have: 1420000, needed: 1420001/)
+        }, /Not enough funds \(incl. fee\): 1420000 < 1420001/)
       })
     })
   })
 
-  describe('createTxAsync', function(){
-    var to, value, fee
-
-    beforeEach(function(){
-      to = '15mMHKL96tWAUtqF3tbVf99Z8arcmnJrr3'
-      value = 500000
-      fee = 10000
-    })
-
-    afterEach(function(){
-      wallet.createTx.restore()
-    })
-
-    it('calls createTx', function(done){
-      sinon.stub(wallet, "createTx").returns("fakeTx")
-
-      var callback = function(err, tx){
-        assert(wallet.createTx.calledWith(to, value))
-        assert.equal(err, null)
-        assert.equal(tx, "fakeTx")
-        done()
-      }
-
-      wallet.createTxAsync(to, value, callback)
-    })
-
-    it('calls createTx correctly when fee is specified', function(done){
-      sinon.stub(wallet, "createTx").returns("fakeTx")
-
-      var callback = function(err, tx){
-        assert(wallet.createTx.calledWith(to, value, fee))
-        assert.equal(err, null)
-        assert.equal(tx, "fakeTx")
-        done()
-      }
-
-      wallet.createTxAsync(to, value, fee, callback)
-    })
-
-    it('when createTx throws an error, it invokes callback with error', function(done){
-      sinon.stub(wallet, "createTx").throws()
-
-      var callback = function(err, tx){
-        assert(err instanceof Error)
-        done()
-      }
-
-      wallet.createTxAsync(to, value, callback)
-    })
-  })
-
   function assertEqual(obj1, obj2){
     assert.equal(obj1.toString(), obj2.toString())
   }