From 2d8df85aab780f6ceecf64701ae41c836fca4052 Mon Sep 17 00:00:00 2001
From: ThomasV <thomasv@electrum.org>
Date: Mon, 13 Mar 2017 11:02:25 +0100
Subject: [PATCH] use maxint-2 to signal RBF, in order to standardize with
 Bitcoin Core

---
 gui/kivy/uix/dialogs/tx_dialog.py | 2 +-
 gui/kivy/uix/screens.py           | 2 +-
 gui/qt/main_window.py             | 6 +++---
 lib/commands.py                   | 2 +-
 lib/transaction.py                | 5 +++--
 5 files changed, 9 insertions(+), 8 deletions(-)

diff --git a/gui/kivy/uix/dialogs/tx_dialog.py b/gui/kivy/uix/dialogs/tx_dialog.py
index 640d635eb..00564cfcb 100644
--- a/gui/kivy/uix/dialogs/tx_dialog.py
+++ b/gui/kivy/uix/dialogs/tx_dialog.py
@@ -148,7 +148,7 @@ class TxDialog(Factory.Popup):
             self.app.show_error(str(e))
             return
         if is_final:
-            new_tx.set_sequence(0xffffffff)
+            new_tx.set_rbf(False)
         self.tx = new_tx
         self.update()
         self.do_sign()
diff --git a/gui/kivy/uix/screens.py b/gui/kivy/uix/screens.py
index 272d7e540..af424b4a5 100644
--- a/gui/kivy/uix/screens.py
+++ b/gui/kivy/uix/screens.py
@@ -284,7 +284,7 @@ class SendScreen(CScreen):
             self.app.show_error(str(e))
             return
         if rbf:
-            tx.set_sequence(0)
+            tx.set_rbf(True)
         fee = tx.get_fee()
         msg = [
             _("Amount to be sent") + ": " + self.app.format_amount_and_units(amount),
diff --git a/gui/qt/main_window.py b/gui/qt/main_window.py
index a3213437e..9e5097d5e 100644
--- a/gui/qt/main_window.py
+++ b/gui/qt/main_window.py
@@ -1306,7 +1306,7 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, PrintError):
 
         use_rbf = self.rbf_checkbox.isChecked()
         if use_rbf:
-            tx.set_sequence(0)
+            tx.set_rbf(True)
 
         if fee < self.wallet.relayfee() * tx.estimated_size() / 1000 and tx.requires_fee(self.wallet):
             self.show_error(_("This transaction requires a higher fee, or it will not be propagated by the network"))
@@ -2823,7 +2823,7 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, PrintError):
             self.show_error(_('Max fee exceeded'))
             return
         new_tx = self.wallet.cpfp(parent_tx, fee)
-        new_tx.set_sequence(0)
+        new_tx.set_rbf(True)
         self.show_transaction(new_tx)
 
     def bump_fee_dialog(self, tx):
@@ -2860,5 +2860,5 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, PrintError):
             self.show_error(str(e))
             return
         if is_final:
-            new_tx.set_sequence(0xffffffff)
+            new_tx.set_rbf(False)
         self.show_transaction(new_tx)
diff --git a/lib/commands.py b/lib/commands.py
index fd0273bcf..41199989f 100644
--- a/lib/commands.py
+++ b/lib/commands.py
@@ -414,7 +414,7 @@ class Commands:
         coins = self.wallet.get_spendable_coins(domain)
         tx = self.wallet.make_unsigned_transaction(coins, final_outputs, self.config, fee, change_addr)
         if rbf:
-            tx.set_sequence(0)
+            tx.set_rbf(True)
         if not unsigned:
             self.wallet.sign_transaction(tx, self._password)
         return tx
diff --git a/lib/transaction.py b/lib/transaction.py
index e7d5c0266..6048bac0d 100644
--- a/lib/transaction.py
+++ b/lib/transaction.py
@@ -681,9 +681,10 @@ class Transaction:
         s += int_to_hex(txin.get('sequence', 0xffffffff), 4)
         return s
 
-    def set_sequence(self, n):
+    def set_rbf(self, rbf):
+        nSequence = 0xffffffff - (2 if rbf else 0)
         for txin in self.inputs():
-            txin['sequence'] = n
+            txin['sequence'] = nSequence
 
     def BIP_LI01_sort(self):
         # See https://github.com/kristovatlas/rfc/blob/master/bips/bip-li01.mediawiki