From 37c488c802575b44854178d5092a957bd6a60b70 Mon Sep 17 00:00:00 2001
From: Christopher Jeffrey <chjjeffrey@gmail.com>
Date: Sat, 26 Mar 2016 01:29:04 -0700
Subject: [PATCH] txdb and mempool work.

---
 lib/bcoin/fullnode.js |  33 ++--
 lib/bcoin/mempool.js  | 119 +++++++-------
 lib/bcoin/txdb.js     | 354 ++++++++++++++++++++++++++----------------
 test/wallet-test.js   |  19 ++-
 4 files changed, 303 insertions(+), 222 deletions(-)

diff --git a/lib/bcoin/fullnode.js b/lib/bcoin/fullnode.js
index c042f554..e5f6c435 100644
--- a/lib/bcoin/fullnode.js
+++ b/lib/bcoin/fullnode.js
@@ -118,12 +118,21 @@ Fullnode.prototype._init = function _init() {
 
   // Update the mempool.
   this.chain.on('add block', function(block) {
-    self.mempool.addBlock(block);
+    self.mempool.addBlock(block, function(err) {
+      if (err)
+        self.emit('error', err);
+    });
   });
 
   this.chain.on('remove block', function(block) {
-    self.mempool.removeBlock(block);
-    self.walletdb.removeBlock(block);
+    self.mempool.removeBlock(block, function(err) {
+      if (err)
+        self.emit('error', err);
+    });
+    self.walletdb.removeBlock(block, function(err) {
+      if (err)
+        self.emit('error', err);
+    });
   });
 
   function load(err) {
@@ -149,7 +158,7 @@ Fullnode.prototype._init = function _init() {
 
     self.createWallet(options, function(err, wallet) {
       if (err)
-        throw err;
+        return self.emit('error', err);
 
       // Set the miner payout address if the
       // programmer didn't pass one in.
@@ -340,22 +349,14 @@ Fullnode.prototype.getTXByAddress = function getTXByAddress(addresses, callback)
 Fullnode.prototype.fillCoin = function fillCoin(tx, callback) {
   var self = this;
 
-  this.mempool.tx.isDoubleSpend(tx, function(err, result) {
+  this.mempool.fillCoin(tx, function(err) {
     if (err)
       return callback(err);
 
-    if (result)
-      return callback(null, tx, true);
+    if (tx.hasPrevout())
+      return callback(null, tx);
 
-    self.mempool.fillCoin(tx, function(err) {
-      if (err)
-        return callback(err);
-
-      if (tx.hasPrevout())
-        return callback(null, tx);
-
-      self.chain.db.fillCoin(tx, callback);
-    });
+    self.chain.db.fillCoin(tx, callback);
   });
 };
 
diff --git a/lib/bcoin/mempool.js b/lib/bcoin/mempool.js
index 00408e50..ddfe0d1a 100644
--- a/lib/bcoin/mempool.js
+++ b/lib/bcoin/mempool.js
@@ -31,7 +31,6 @@ function Mempool(node, options) {
   this.options = options;
   this.node = node;
   this.chain = node.chain;
-  // this.db = node.chain.db.db;
 
   this.db = bcoin.ldb('mempool', {
     db: 'memdown'
@@ -100,22 +99,34 @@ Mempool.prototype.open = function open(callback) {
   return this.db.open(callback);
 };
 
-Mempool.prototype.addBlock = function addBlock(block, callback) {
+Mempool.prototype.addBlock = function addBlock(block, callback, force) {
   var self = this;
-  callback = utils.ensure(callback);
-  // Remove now-mined transactions
-  // XXX should batch this
-  utils.forEachSerial(block.txs, function(tx, next) {
-    self.tx.remove(tx, next);
-  }, callback);
+  var unlock = this._lock(addBlock, [block, callback], force);
+  if (!unlock)
+    return;
+
+  callback = utils.wrap(callback, unlock);
+
+  this.open(function(err) {
+    if (err)
+      return callback(err);
+
+    utils.forEachSerial(block.txs, function(tx, next) {
+      self.tx.removeUnchecked(tx, next);
+    }, callback);
+  });
 };
 
-Mempool.prototype.removeBlock = function removeBlock(block, callback) {
+Mempool.prototype.removeBlock = function removeBlock(block, callback, force) {
   var self = this;
-  callback = utils.ensure(callback);
-  // XXX should batch this
+  var unlock = this._lock(removeBlock, [block, callback], force);
+  if (!unlock)
+    return;
+
+  callback = utils.wrap(callback, unlock);
+
   utils.forEachSerial(block.txs.slice().reverse(), function(tx, next) {
-    self.tx.add(tx, next);
+    self.tx.addUnchecked(tx, next);
   }, callback);
 };
 
@@ -208,7 +219,7 @@ Mempool.prototype.addTX = function addTX(tx, peer, callback, force) {
     if (exists)
       return callback();
 
-    self.node.fillCoin(tx, function(err, tx, doubleSpend) {
+    self.tx.isDoubleSpend(tx, function(err, doubleSpend) {
       if (err)
         return callback(err);
 
@@ -217,17 +228,22 @@ Mempool.prototype.addTX = function addTX(tx, peer, callback, force) {
         return callback(new VerifyError('bad-txns-inputs-spent', 0));
       }
 
-      if (!tx.hasPrevout())
-        return self.storeOrphan(tx, callback);
-
-      self.verify(tx, function(err) {
-        if (err) {
-          if (err.type === 'VerifyError' && err.score >= 0)
-            peer.sendReject(tx, err.reason, err.score);
+      self.node.fillCoin(tx, function(err) {
+        if (err)
           return callback(err);
-        }
 
-        self.addUnchecked(tx, peer, callback);
+        if (!tx.hasPrevout())
+          return self.storeOrphan(tx, callback);
+
+        self.verify(tx, function(err) {
+          if (err) {
+            if (err.type === 'VerifyError' && err.score >= 0)
+              peer.sendReject(tx, err.reason, err.score);
+            return callback(err);
+          }
+
+          self.addUnchecked(tx, peer, callback);
+        });
       });
     });
   });
@@ -235,7 +251,7 @@ Mempool.prototype.addTX = function addTX(tx, peer, callback, force) {
 
 Mempool.prototype.addUnchecked = function addUnchecked(tx, peer, callback) {
   var self = this;
-  self.tx.add(tx, function(err) {
+  self.tx.addUnchecked(tx, function(err) {
     if (err)
       return callback(err);
 
@@ -351,7 +367,7 @@ Mempool.prototype._hasTX = function hasTX(tx, callback, force) {
     if (result)
       return callback(null, result);
 
-    self.db.get('D/' + hash, function(err, tx) {
+    self.db.get('m/D/' + hash, function(err, tx) {
       if (err && err.type !== 'NotFoundError')
         return callback(err);
 
@@ -378,7 +394,7 @@ Mempool.prototype.storeOrphan = function storeOrphan(tx, callback, force) {
   assert(outputs.length > 0);
 
   utils.forEachSerial(outputs, function(key, next) {
-    self.db.get('d/' + key, function(err, buf) {
+    self.db.get('m/d/' + key, function(err, buf) {
       if (err && err.type !== 'NotFoundError')
         return next(err);
 
@@ -389,7 +405,7 @@ Mempool.prototype.storeOrphan = function storeOrphan(tx, callback, force) {
 
       p.writeHash(hash);
 
-      batch.put('d/' + key, p.render());
+      batch.put('m/d/' + key, p.render());
 
       next();
     });
@@ -397,7 +413,7 @@ Mempool.prototype.storeOrphan = function storeOrphan(tx, callback, force) {
     if (err)
       return callback(err);
 
-    batch.put('D/' + hash, tx.toExtended(true));
+    batch.put('m/D/' + hash, tx.toExtended(true));
     batch.write(callback);
   });
 };
@@ -418,7 +434,7 @@ Mempool.prototype.resolveOrphans = function resolveOrphans(tx, callback, force)
   var batch = this.db.batch();
   var p;
 
-  this.db.get('d/' + hash, function(err, buf) {
+  this.db.get('m/d/' + hash, function(err, buf) {
     if (err && err.type !== 'NotFoundError')
       return callback(err);
 
@@ -439,7 +455,7 @@ Mempool.prototype.resolveOrphans = function resolveOrphans(tx, callback, force)
     p.end();
 
     utils.forEachSerial(hashes, function(orphanHash, next, i) {
-      self.db.get('D/' + orphanHash, function(err, orphan) {
+      self.db.get('m/D/' + orphanHash, function(err, orphan) {
         if (err && err.type !== 'NotFoundError')
           return next(err);
 
@@ -452,10 +468,13 @@ Mempool.prototype.resolveOrphans = function resolveOrphans(tx, callback, force)
           return next(e);
         }
 
-        orphan.fillPrevout(tx);
+        orphan.inputs.forEach(function(input) {
+          if (!input.output && input.prevout.hash === hash)
+            input.output = bcoin.coin(tx, input.prevout.index);
+        });
 
         if (orphan.hasPrevout()) {
-          batch.del('D/' + orphanHash);
+          batch.del('m/D/' + orphanHash);
           return self.verify(orphan, function(err) {
             if (err) {
               if (err.type === 'VerifyError')
@@ -467,7 +486,7 @@ Mempool.prototype.resolveOrphans = function resolveOrphans(tx, callback, force)
           });
         }
 
-        batch.put('D/' + orphanHash, orphan.toExtended(true));
+        batch.put('m/D/' + orphanHash, orphan.toExtended(true));
         next();
       });
     }, function(err) {
@@ -481,7 +500,7 @@ Mempool.prototype.resolveOrphans = function resolveOrphans(tx, callback, force)
         return callback(null, resolved);
       }
 
-      batch.del('d/' + hash);
+      batch.del('m/d/' + hash);
 
       return batch.write(done);
     });
@@ -492,40 +511,6 @@ Mempool.prototype.getInv = function getInv(callback) {
   return this.tx.getAllHashes(callback);
 };
 
-Mempool.prototype.remove =
-Mempool.prototype.removeTX = function removeTX(hash, callback, force) {
-  var self = this;
-
-  var unlock = this._lock(removeTX, [hash, callback], force);
-  if (!unlock)
-    return;
-
-  function getTX() {
-    if (hash instanceof bcoin.tx)
-      return callback(null, hash);
-
-    return self.getTX(hash, function(err, tx) {
-      if (err)
-        return callback(err);
-      if (!tx)
-        return callback();
-      return self.node.fillTX(tx, callback);
-    });
-  }
-
-  return getTX(function(err, tx) {
-    if (err)
-      return callback(err);
-
-    self.tx.remove(tx, function(err) {
-      if (err)
-        return callback(err);
-
-      self.emit('remove tx', tx);
-    });
-  });
-};
-
 Mempool.prototype.checkTX = function checkTX(tx, peer) {
   return Mempool.checkTX(tx, peer);
 };
diff --git a/lib/bcoin/txdb.js b/lib/bcoin/txdb.js
index 1f8d6559..3d6998b6 100644
--- a/lib/bcoin/txdb.js
+++ b/lib/bcoin/txdb.js
@@ -30,6 +30,7 @@ function TXPool(prefix, db, options) {
   this.options = options;
   this.busy = false;
   this.jobs = [];
+  this.locker = new bcoin.locker(this);
 
   if (this.options.mapAddress)
     this.options.indexAddress = true;
@@ -38,40 +39,7 @@ function TXPool(prefix, db, options) {
 utils.inherits(TXPool, EventEmitter);
 
 TXPool.prototype._lock = function _lock(func, args, force) {
-  var self = this;
-  var called;
-
-  if (force) {
-    assert(this.busy);
-    return function unlock() {
-      assert(!called);
-      called = true;
-    };
-  }
-
-  if (this.busy) {
-    this.jobs.push([func, args]);
-    return;
-  }
-
-  this.busy = true;
-
-  return function unlock() {
-    var item;
-
-    assert(!called);
-    called = true;
-
-    self.busy = false;
-
-    if (self.jobs.length === 0) {
-      self.emit('flush');
-      return;
-    }
-
-    item = self.jobs.shift();
-    item[0].apply(self, item[1]);
-  };
+  return this.locker.lock(func, args, force);
 };
 
 TXPool.prototype.getMap = function getMap(tx, callback) {
@@ -325,20 +293,24 @@ TXPool.prototype._add = function add(tx, map, callback, force) {
 
     // Consume unspent money or add orphans
     utils.forEachSerial(tx.inputs, function(input, next, i) {
-      var key;
+      var key, address;
 
       if (tx.isCoinbase())
         return next();
 
-      key = input.prevout.hash + '/' + input.prevout.index;
+      address = input.getAddress();
+
+      // Only add orphans if this input is ours.
+      if (self.options.mapAddress) {
+        if (!address || !map[address].length)
+          return next();
+      }
 
       self.getCoin(input.prevout.hash, input.prevout.index, function(err, coin) {
-        var address;
-
         if (err)
           return next(err);
 
-        address = input.getAddress();
+        key = input.prevout.hash + '/' + input.prevout.index;
 
         if (coin) {
           // Add TX to inputs and spend money
@@ -354,50 +326,52 @@ TXPool.prototype._add = function add(tx, map, callback, force) {
 
           if (self.options.indexAddress && address) {
             map[address].forEach(function(id) {
-              batch.del(
-                prefix + 'u/a/' + id
-                + '/' + input.prevout.hash
-                + '/' + input.prevout.index);
+              batch.del(prefix + 'u/a/' + id + '/' + key);
             });
           }
 
-          batch.del(
-            prefix + 'u/t/'
-            + input.prevout.hash
-            + '/' + input.prevout.index);
-
-          if (self.options.indexSpent) {
-            batch.put(
-              prefix + 's/t/'
-              + input.prevout.hash
-              + '/' + input.prevout.index,
-              tx.hash());
-          }
+          batch.del(prefix + 'u/t/' + key);
+          batch.put(prefix + 's/t/' + key, tx.hash());
 
           return next();
         }
 
         input.output = null;
 
-        // Only add orphans if this input is ours.
-        if (self.options.mapAddress) {
-          if (!address || !map[address].length)
-            return next();
-        }
-
-        self.isSpent(input.prevout.hash, input.prevout.index, function(err, result) {
+        self.isSpent(input.prevout.hash, input.prevout.index, function(err, spentBy) {
           if (err)
             return next(err);
 
           // Are we double-spending?
-          if (result) {
-            if (!self.options.indexSpent)
-              return next(new Error('Transaction is double-spending.'));
-            return self._removeSpenders(hash, function(err) {
+          // Replace older txs with newer ones.
+          if (spentBy) {
+            return self.getTX(input.prevout.hash, function(err, prev) {
               if (err)
                 return next(err);
-              batch.clear();
-              self._add(tx, map, callback, true);
+
+              if (!prev)
+                return callback(new Error('Could not find double-spent coin.'));
+
+              input.output = bcoin.coin(prev, input.prevout.index);
+
+              // Skip invalid transactions
+              if (self.options.verify) {
+                if (!tx.verify(i))
+                  return callback(null, false);
+              }
+
+              return self._removeSpenders(spentBy, tx, function(err, result) {
+                if (err)
+                  return next(err);
+
+                if (!result) {
+                  assert(tx.ts === 0, 'I\'m confused');
+                  return callback(null, false);
+                }
+
+                batch.clear();
+                self._add(tx, map, callback, true);
+              });
             });
           }
 
@@ -525,7 +499,7 @@ TXPool.prototype._add = function add(tx, map, callback, force) {
   }, true);
 };
 
-TXPool.prototype._removeSpenders = function removeSpenders(hash, callback) {
+TXPool.prototype._removeSpenders = function removeSpenders(hash, ref, callback) {
   var self = this;
   this.getTX(hash, function(err, tx) {
     if (err)
@@ -535,54 +509,31 @@ TXPool.prototype._removeSpenders = function removeSpenders(hash, callback) {
       return callback(new Error('Could not find spender.'));
 
     if (tx.ts !== 0)
-      return callback(new Error('Transaction is double-spending.'));
+      return callback(null, false);
 
-    utils.forEachSerial(tx.outputs, function(next, output, i) {
+    if (ref.ts === 0 && ref.ps < ts.ps)
+      return callback(null, false);
+
+    utils.forEachSerial(tx.outputs, function(output, next, i) {
       self.isSpent(hash, i, function(err, spent) {
         if (err)
           return next(err);
         if (spent)
-          return self._removeSpenders(spent, next);
+          return self._removeSpenders(spent, ref, next);
         next();
       });
     }, function(err) {
       if (err)
         return callback(err);
-      return self.lazyRemove(tx, callback, true);
+      return self.lazyRemove(tx, function(err) {
+        if (err)
+          return callback(err);
+        return callback(null, true);
+      }, true);
     });
   });
 };
 
-TXPool.prototype._collectSpenders = function _collectSpenders(tx, callback, spenders) {
-  var self = this;
-  var hash = tx.hash('hex');
-
-  if (!spenders)
-    spenders = [];
-
-  utils.forEachSerial(tx.outputs, function(next, output, i) {
-    self.isSpent(hash, i, function(err, spentBy) {
-      if (err)
-        return next(err);
-      if (spentBy) {
-        spenders.push(spentBy);
-        return self.getTX(spentBy, function(err, tx) {
-          if (err)
-            return next(err);
-          if (!tx)
-            return next();
-          return self._removeSpenders(tx, next, spenders);
-        });
-      }
-      next();
-    });
-  }, function(err) {
-    if (err)
-      return callback(err);
-    return callback(null, spenders);
-  });
-};
-
 TXPool.prototype.isDoubleSpend = function isDoubleSpend(tx, callback) {
   var self = this;
   utils.everySerial(tx.inputs, function(input, next) {
@@ -601,36 +552,19 @@ TXPool.prototype.isDoubleSpend = function isDoubleSpend(tx, callback) {
   });
 };
 
-TXPool.prototype.isSpent = function isSpent(hash, index, callback, checkCoin) {
+TXPool.prototype.isSpent = function isSpent(hash, index, callback) {
   var self = this;
+  var prefix = this.prefix + '/';
+  var key = prefix + 's/t/' + hash + '/' + index;
 
-  if (this.options.indexSpent) {
-    return this.db.get('s/t/' + hash + '/' + index, function(err, exists) {
-      if (err && err.type !== 'NotFoundError')
-        return callback(err);
-
-      return callback(null, exists ? exists.toString('hex') : null);
-    });
-  }
-
-  function getCoin(callback) {
-    if (!checkCoin)
-      return callback(null, null);
-    return self.getCoin(hash, index, callback);
-  }
-
-  return getCoin(function(err, coin) {
-    if (err)
+  return this.db.get(key, function(err, hash) {
+    if (err && err.type !== 'NotFoundError')
       return callback(err);
 
-    if (coin)
-      return callback(null, false);
+    if (!hash)
+      return callback(null, null);
 
-    return self.getTX(hash, function(err, tx) {
-      if (err)
-        return callback(err);
-      return callback(null, !!tx);
-    });
+    return callback(null, utils.toHex(hash));
   });
 };
 
@@ -728,10 +662,6 @@ TXPool.prototype._confirm = function _confirm(tx, map, callback, force) {
 
 TXPool.prototype.remove = function remove(hash, callback, force) {
   var self = this;
-  var first = Array.isArray(hash) ? hash[0] : hash;
-
-  if (!this.options.indexExtra && (first instanceof bcoin.tx))
-    return this.lazyRemove(hash, callback, force);
 
   if (Array.isArray(hash)) {
     return utils.forEachSerial(hash, function(hash, next) {
@@ -858,11 +788,9 @@ TXPool.prototype._remove = function remove(tx, map, callback, force) {
         + '/' + input.prevout.index,
         input.output.toRaw());
 
-      if (self.options.indexSpent) {
-        batch.del(prefix + 's/t/'
-          + input.prevout.hash
-          + '/' + input.prevout.index);
-      }
+      batch.del(prefix + 's/t/'
+        + input.prevout.hash
+        + '/' + input.prevout.index);
 
       batch.del(prefix + 'o/' + input.prevout.hash + '/' + input.prevout.index);
     });
@@ -1603,6 +1531,158 @@ TXPool.prototype.getBalance = function getBalance(callback) {
   return this.getBalanceByAddress(null, callback);
 };
 
+TXPool.prototype.addUnchecked = function addUnchecked(tx, callback, force) {
+  var self = this;
+  var prefix = this.prefix + '/';
+  var hash = tx.hash('hex');
+  var batch;
+
+  var unlock = this._lock(addUnchecked, [tx, callback], force);
+  if (!unlock)
+    return;
+
+  callback = utils.wrap(callback, unlock);
+
+  batch = this.db.batch();
+
+  batch.put(prefix + 't/t/' + hash, tx.toExtended());
+
+  tx.getAddresses().forEach(function(address) {
+    batch.put(prefix + 't/a/' + address + '/' + hash, DUMMY);
+  });
+
+  tx.inputs.forEach(function(input) {
+    var key = input.prevout.hash + '/' + input.prevout.index;
+    var address;
+
+    if (tx.isCoinbase())
+      return;
+
+    assert(input.output);
+    address = input.getAddress();
+
+    batch.del(prefix + 'u/t/' + key);
+    batch.put(prefix + 's/t/' + key, tx.hash());
+
+    if (address)
+      batch.del(prefix + 'u/a/' + address + '/' + key);
+  });
+
+  tx.outputs.forEach(function(output, i) {
+    var key = hash + '/' + i;
+    var address = output.getAddress();
+    var coin = bcoin.coin(tx, i).toRaw();
+    batch.put(prefix + 'u/t/' + key, coin);
+
+    if (address)
+      batch.put(prefix + 'u/a/' + address + '/' + key, DUMMY);
+  });
+
+  return batch.write(function(err) {
+    if (err)
+      return callback(err);
+    self.emit('add tx', tx);
+    return callback();
+  });
+};
+
+TXPool.prototype.removeUnchecked = function removeUnchecked(tx, callback, force) {
+  var self = this;
+  var prefix = this.prefix + '/';
+  var hash = tx.hash('hex');
+  var batch;
+
+  var unlock = this._lock(removeUnchecked, [tx, callback], force);
+  if (!unlock)
+    return;
+
+  callback = utils.wrap(callback, unlock);
+
+  batch = this.db.batch();
+
+  batch.del(prefix + 't/t/' + hash);
+  batch.del(prefix + 'D/' + hash);
+
+  tx.getAddresses().forEach(function(address) {
+    batch.del(prefix + 't/a/' + address + '/' + hash);
+  });
+
+  tx.inputs.forEach(function(input) {
+    var key = input.prevout.hash + '/' + input.prevout.index;
+    var address;
+
+    if (tx.isCoinbase())
+      return;
+
+    if (!input.output)
+      return;
+
+    address = input.getAddress();
+
+    batch.del(prefix + 'u/t/' + key);
+    batch.del(prefix + 's/t/' + key);
+
+    if (address)
+      batch.del(prefix + 'u/a/' + address + '/' + key);
+  });
+
+  tx.outputs.forEach(function(output, i) {
+    var key = hash + '/' + i;
+    var address = output.getAddress();
+
+    batch.del(prefix + 'u/t/' + key);
+
+    if (address)
+      batch.del(prefix + 'u/a/' + address + '/' + key);
+  });
+
+  batch.write(function(err) {
+    if (err)
+      return callback(err);
+    self.emit('remove tx', tx);
+    return callback();
+  });
+};
+
+TXPool.prototype.zap = function zap(tip, callback, force) {
+  var self = this;
+  var now = tip.ts;
+  var age = 10 * 60 * 60;
+
+  var unlock = this._lock(zap, [tip, callback], force);
+  if (!unlock)
+    return;
+
+  callback = utils.wrap(callback, unlock);
+
+  // return this.getRange(null, {
+  //   start: 0,
+  //   end: now - age
+  // }, function(err, txs) {
+  // });
+
+  this.getPending(function(err, txs) {
+    if (err)
+      return callback(err);
+
+    txs = txs.filter(function(tx) {
+      return now > tx.ps + age;
+    });
+
+    if (txs.length === 0)
+      return callback();
+
+    self.fillTX(txs, function(err) {
+      if (err)
+        return callback(err);
+
+      utils.forEachSerial(txs, function(tx, next) {
+        self.lazyRemove(tx, next);
+      }, callback);
+    });
+  });
+};
+
 /**
  * Expose
  */
diff --git a/test/wallet-test.js b/test/wallet-test.js
index feb32655..fa2cab82 100644
--- a/test/wallet-test.js
+++ b/test/wallet-test.js
@@ -19,6 +19,7 @@ var dummyInput = {
     index: 0
   },
   script: new bcoin.script([]),
+  witness: new bcoin.script.witness([]),
   sequence: 0xffffffff
 };
 
@@ -131,11 +132,13 @@ describe('Wallet', function() {
     assert(tx.verify());
   });
 
+  var dw, di;
   it('should have TX pool and be serializable', function(cb) {
     wdb.create({}, function(err, w) {
       assert.noError(err);
       wdb.create({}, function(err, f) {
         assert.noError(err);
+        dw = w;
 
         // Coinbase
         var t1 = bcoin.mtx().addOutput(w, 50000).addOutput(w, 1000);
@@ -145,6 +148,7 @@ describe('Wallet', function() {
         var t2 = bcoin.mtx().addInput(t1, 0) // 50000
                            .addOutput(w, 24000)
                            .addOutput(w, 24000);
+        di = t2.inputs[0];
         // balance: 49000
         w.sign(t2);
         var t3 = bcoin.mtx().addInput(t1, 1) // 1000
@@ -179,8 +183,6 @@ describe('Wallet', function() {
         fake.hint = 'fake';
 
         // Fake TX should temporarly change output
-        // wdb.addTX(fake);
-
         wdb.addTX(fake, function(err) {
           assert.noError(err);
           wdb.addTX(t4, function(err) {
@@ -234,6 +236,19 @@ describe('Wallet', function() {
     });
   });
 
+  it('should cleanup spenders after double-spend', function(cb) {
+    var t1 = bcoin.mtx().addOutput(dw, 5000);
+    t1.addInput(di);
+    wdb.addTX(t1, function(err) {
+      assert.noError(err);
+      dw.getBalance(function(err, balance) {
+        assert.noError(err);
+        assert.equal(balance.toString(10), '11000');
+        cb();
+      });
+    });
+  });
+
   it('should fill tx with inputs', function(cb) {
     wdb.create({}, function(err, w1) {
       assert.noError(err);