Transaction: add internal flag to disable size assertion

src/transaction.js

@@ -22,7 +22,7 @@ Transaction.SIGHASH_NONE = 0x02
 Transaction.SIGHASH_SINGLE = 0x03
 Transaction.SIGHASH_ANYONECANPAY = 0x80
 
-Transaction.fromBuffer = function(buffer) {
+Transaction.fromBuffer = function(buffer, __disableAssert) {
   var offset = 0
   function readSlice(n) {
     offset += n
@@ -73,7 +73,10 @@ Transaction.fromBuffer = function(buffer) {
   }
 
   tx.locktime = readUInt32()
-  assert.equal(offset, buffer.length, 'Transaction has unexpected data')
+
+  if (!__disableAssert) {
+    assert.equal(offset, buffer.length, 'Transaction has unexpected data')
+  }
 
   return tx
 }