transaction: always sort i/o deterministically

this was previously the caller's responsibility; now it's done implicitly when creating a txn

electrum/transaction.py

@@ -747,6 +747,7 @@ class Transaction:
         self._inputs = inputs
         self._outputs = outputs
         self.locktime = locktime
+        self.BIP69_sort()
         return self
 
     @classmethod
@@ -981,10 +982,11 @@ class Transaction:
         for txin in self.inputs():
             txin['sequence'] = nSequence
 
-    def BIP_LI01_sort(self):
-        # See https://github.com/kristovatlas/rfc/blob/master/bips/bip-li01.mediawiki
-        self._inputs.sort(key = lambda i: (i['prevout_hash'], i['prevout_n']))
-        self._outputs.sort(key = lambda o: (o[2], self.pay_script(o[0], o[1])))
+    def BIP69_sort(self, inputs=True, outputs=True):
+        if inputs:
+            self._inputs.sort(key = lambda i: (i['prevout_hash'], i['prevout_n']))
+        if outputs:
+            self._outputs.sort(key = lambda o: (o[2], self.pay_script(o[0], o[1])))
 
     def serialize_output(self, output):
         output_type, addr, amount = output
@@ -1070,10 +1072,12 @@ class Transaction:
     def add_inputs(self, inputs):
         self._inputs.extend(inputs)
         self.raw = None
+        self.BIP69_sort(outputs=False)
 
     def add_outputs(self, outputs):
         self._outputs.extend(outputs)
         self.raw = None
+        self.BIP69_sort(inputs=False)
 
     def input_value(self):
         return sum(x['value'] for x in self.inputs())

electrum/wallet.py

@@ -143,7 +143,6 @@ def sweep(privkeys, network, config, recipient, fee=None, imax=100):
     locktime = network.get_local_height()
 
     tx = Transaction.from_io(inputs, outputs, locktime=locktime)
-    tx.BIP_LI01_sort()
     tx.set_rbf(True)
     tx.sign(keypairs)
     return tx
@@ -608,8 +607,6 @@ class Abstract_Wallet(AddressSynchronizer):
             outputs[i_max] = outputs[i_max]._replace(value=amount)
             tx = Transaction.from_io(inputs, outputs[:])
 
-        # Sort the inputs and outputs deterministically
-        tx.BIP_LI01_sort()
         # Timelock tx to current height.
         tx.locktime = self.get_local_height()
         run_hook('make_unsigned_transaction', self, tx)
@@ -714,7 +711,6 @@ class Abstract_Wallet(AddressSynchronizer):
             raise CannotBumpFee(_('Cannot bump fee') + ': ' + _('could not find suitable outputs'))
         locktime = self.get_local_height()
         tx_new = Transaction.from_io(inputs, outputs, locktime=locktime)
-        tx_new.BIP_LI01_sort()
         return tx_new
 
     def cpfp(self, tx, fee):
@@ -733,7 +729,6 @@ class Abstract_Wallet(AddressSynchronizer):
         inputs = [item]
         outputs = [TxOutput(TYPE_ADDRESS, address, value - fee)]
         locktime = self.get_local_height()
-        # note: no need to call tx.BIP_LI01_sort() here - single input/output
         return Transaction.from_io(inputs, outputs, locktime=locktime)
 
     def add_input_sig_info(self, txin, address):