From 2dfdae9d7397e394488c206ac68990eccae4bafd Mon Sep 17 00:00:00 2001
From: holgerd77 <Holger.Drewes@gmail.com>
Date: Fri, 29 Jun 2018 14:36:01 +0200
Subject: [PATCH 1/2] Do not set default zero adress, only include signature
 with from set in fake transaction (undo PR #94)

---
 fake.js | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/fake.js b/fake.js
index 3dc0342..91ab0c6 100644
--- a/fake.js
+++ b/fake.js
@@ -49,8 +49,7 @@ module.exports = class FakeTransaction extends Transaction {
       }
     })
 
-    // set from address or default to null address
-    this.from = (data && data.from) ? data.from : '0x0000000000000000000000000000000000000000'
+    this.from = data.from
   }
 
   /**
@@ -59,7 +58,7 @@ module.exports = class FakeTransaction extends Transaction {
    * @return {Buffer}
    */
   hash (includeSignature = true) {
-    if (includeSignature) {
+    if (includeSignature && this._from && this._from.toString('hex') !== '') {
       // include a fake signature using the from address as a private key
       let fakeKey = Buffer.concat([this._from, this._from.slice(0, 12)])
       this.sign(fakeKey)

From 0bd25a1143f4a828dc49cc8bf2a614e143f1ac20 Mon Sep 17 00:00:00 2001
From: holgerd77 <Holger.Drewes@gmail.com>
Date: Fri, 29 Jun 2018 14:36:58 +0200
Subject: [PATCH 2/2] Added tests for instantiating and hash creation of a fake
 tx with and without from set

---
 test/fake.js | 58 ++++++++++++++++++++++++++++++++++++++--------------
 1 file changed, 43 insertions(+), 15 deletions(-)

diff --git a/test/fake.js b/test/fake.js
index b41cd7a..49767e3 100644
--- a/test/fake.js
+++ b/test/fake.js
@@ -1,23 +1,51 @@
 const tape = require('tape')
 const utils = require('ethereumjs-util')
 const FakeTransaction = require('../fake.js')
+
+var txData = {
+  data: '0x7cf5dab00000000000000000000000000000000000000000000000000000000000000005',
+  gasLimit: '0x15f90',
+  gasPrice: '0x1',
+  nonce: '0x01',
+  to: '0xd9024df085d09398ec76fbed18cac0e1149f50dc',
+  value: '0x0',
+  from: '0x1111111111111111111111111111111111111111'
+}
+
 tape('[FakeTransaction]: Basic functions', function (t) {
+  t.test('instantiate with from / create a hash', function (st) {
+    st.plan(3)
+    var tx = new FakeTransaction(txData)
+    var hash = tx.hash()
+    var cmpHash = Buffer.from('f0327c058946be12609d2afc0c45e8e1fffe57acbbff0e9c252e8fab61c3b2b9', 'hex')
+    st.deepEqual(hash, cmpHash, 'should create hash with includeSignature=true (default)')
+    var hash2 = tx.hash(false)
+    var cmpHash2 = Buffer.from('0401bf740d698674be321d0064f92cd6ebba5d73d1e5e5189c0bebbda33a85fe', 'hex')
+    st.deepEqual(hash2, cmpHash2, 'should create hash with includeSignature=false')
+    st.notDeepEqual(hash, hash2, 'previous hashes should be different')
+  })
+
+  t.test('instantiate without from / create a hash', function (st) {
+    var txDataNoFrom = Object.assign({}, txData)
+    delete txDataNoFrom['from']
+    st.plan(3)
+    var tx = new FakeTransaction(txDataNoFrom)
+    var hash = tx.hash()
+    var cmpHash = Buffer.from('7521eb94880840a93e2105f064cec3fe605f0159778a420b9b529c2f3d3b4e37', 'hex')
+    st.deepEqual(hash, cmpHash, 'should create hash with includeSignature=true (default)')
+    var hash2 = tx.hash(false)
+    var cmpHash2 = Buffer.from('0401bf740d698674be321d0064f92cd6ebba5d73d1e5e5189c0bebbda33a85fe', 'hex')
+    st.deepEqual(hash2, cmpHash2, 'should create hash with includeSignature=false')
+    st.notDeepEqual(hash, hash2, 'previous hashes should be different')
+  })
+
   t.test('should not produce hash collsions for different senders', function (st) {
     st.plan(1)
-    var baseTxData = {
-      data: '0x7cf5dab00000000000000000000000000000000000000000000000000000000000000005',
-      gasLimit: '0x15f90',
-      gasPrice: '0x1',
-      nonce: '0x01',
-      to: '0xd9024df085d09398ec76fbed18cac0e1149f50dc',
-      value: '0x0',
-      from: '0x1111111111111111111111111111111111111111'
-    }
-    var modifiedFromFieldTxData = Object.assign({}, baseTxData, { from: '0x2222222222222222222222222222222222222222' })
-    var baseTx = new FakeTransaction(baseTxData)
-    var modifiedFromFieldTx = new FakeTransaction(modifiedFromFieldTxData)
-    var baseTxHash = utils.bufferToHex(baseTx.hash())
-    var modifiedFromFieldTxHash = utils.bufferToHex(modifiedFromFieldTx.hash())
-    st.notEqual(baseTxHash, modifiedFromFieldTxHash, 'FakeTransactions with different `from` addresses but otherwise identical data should have different hashes')
+    var txDataModFrom = Object.assign({}, txData, { from: '0x2222222222222222222222222222222222222222' })
+    var tx = new FakeTransaction(txData)
+    var txModFrom = new FakeTransaction(txDataModFrom)
+    var hash = utils.bufferToHex(tx.hash())
+    var hashModFrom = utils.bufferToHex(txModFrom.hash())
+    st.notEqual(hash, hashModFrom, 'FakeTransactions with different `from` addresses but otherwise identical data should have different hashes')
   })
 })