From 1e7e9a2aa75eecb881631c343d6f7d3546e0f55f Mon Sep 17 00:00:00 2001
From: Christopher Jeffrey <chjjeffrey@gmail.com>
Date: Tue, 19 Apr 2016 07:36:05 -0700
Subject: [PATCH] handle negative outputs. serialize int64 correctly.

---
 lib/bcoin/utils.js | 14 ++++++++++----
 test/tx-test.js    |  8 ++++++++
 2 files changed, 18 insertions(+), 4 deletions(-)

diff --git a/lib/bcoin/utils.js b/lib/bcoin/utils.js
index ea0be826..50b6282e 100644
--- a/lib/bcoin/utils.js
+++ b/lib/bcoin/utils.js
@@ -600,6 +600,7 @@ utils.assert = assert;
 utils.btc =
 utils.toBTC = function toBTC(satoshi, strict) {
   var m = new bn(10000000).mul(new bn(10));
+  var neg = false;
   var lo;
 
   if (utils.isBTC(satoshi))
@@ -613,6 +614,11 @@ utils.toBTC = function toBTC(satoshi, strict) {
   if (!satoshi)
     throw new Error('Could not calculate BTC');
 
+  if (satoshi.isNeg()) {
+    satoshi = satoshi.neg();
+    neg = true;
+  }
+
   lo = satoshi.mod(m);
 
   if (lo.cmpn(0) !== 0) {
@@ -628,7 +634,7 @@ utils.toBTC = function toBTC(satoshi, strict) {
   if (lo === '.')
     lo += '0';
 
-  return satoshi.div(m).toString(10) + lo;
+  return (neg ? '-' : '') + satoshi.div(m).toString(10) + lo;
 };
 
 /**
@@ -689,7 +695,7 @@ utils.isInt = function isInt(val) {
  */
 
 utils.isFloat = function isFloat(val) {
-  return typeof val === 'string' && /^\d+\.\d+$/.test(val);
+  return typeof val === 'string' && /^-?\d+\.\d+$/.test(val);
 };
 
 /**
@@ -1980,7 +1986,7 @@ utils.write64 = function write64(dst, num, off) {
     if (num.cmpn(0) === 0)
       num = new bn(0);
     else
-      num = num.neg().notn(64).subn(1);
+      num = num.neg().notn(64).addn(1);
   }
 
   if (num.bitLength() > 64)
@@ -2016,7 +2022,7 @@ utils.write64BE = function write64BE(dst, num, off) {
     if (num.cmpn(0) === 0)
       num = new bn(0);
     else
-      num = num.neg().notn(64).subn(1);
+      num = num.neg().notn(64).addn(1);
   }
 
   if (num.bitLength() > 64)
diff --git a/test/tx-test.js b/test/tx-test.js
index 7c498e6d..983a48f0 100644
--- a/test/tx-test.js
+++ b/test/tx-test.js
@@ -210,6 +210,14 @@ describe('TX', function() {
             });
             return;
           }
+          if (comments === 'Negative output') {
+            it('should handle invalid tx (negative)' + suffix + ': ' + comments, function () {
+              clearCache(tx, nocache);
+              assert.ok(tx.verify(null, true, flags));
+              assert.ok(!tx.isSane());
+            });
+            return;
+          }
           if (comments.indexOf('Coinbase') === 0) {
             it('should handle invalid coinbase' + suffix + ': ' + comments, function () {
               clearCache(tx, nocache);