confirm_tx_dialog: simplify messages and warnings. reduce the use of side effects

electrum/gui/qt/confirm_tx_dialog.py

@@ -67,8 +67,7 @@ class TxEditor(WindowModalDialog):
         self.make_tx = make_tx
         self.output_value = output_value
         self.tx = None  # type: Optional[PartialTransaction]
-        self.message = '' # set by side effect in RBF dialogs
+        self.messages = []
-        self.warning = '' # set by side effect
         self.error = ''   # set by side effect
 
         self.config = window.config
@@ -95,11 +94,9 @@ class TxEditor(WindowModalDialog):
 
         vbox.addLayout(top)
         vbox.addLayout(grid)
+        vbox.addWidget(self.io_widget)
         self.message_label = WWLabel('')
         vbox.addWidget(self.message_label)
-        vbox.addWidget(self.io_widget)
-        self.warning_label = WWLabel('')
-        vbox.addWidget(self.warning_label)
 
         buttons = self.create_buttons_bar()
         vbox.addStretch(1)
@@ -227,7 +224,7 @@ class TxEditor(WindowModalDialog):
     def trigger_update(self):
         # set tx to None so that the ok button is disabled while we compute the new tx
         self.tx = None
-        self.message = ''
+        self.messages = []
         self.error = ''
         self._update_widgets()
         self.needs_update = True
@@ -523,6 +520,7 @@ class TxEditor(WindowModalDialog):
         self.accept()
 
     def _update_widgets(self):
+        # side effect: self.error
         self._update_amount_label()
         if self.not_enough_funds:
             self.error = _('Not enough funds.')
@@ -533,15 +531,13 @@ class TxEditor(WindowModalDialog):
                 self.error += ' ' + _('You need to set a lower fee.')
             else:
                 self.error += ''
-        else:
-            self.error = ''
         if not self.tx:
             if self.not_enough_funds:
                 self.io_widget.update(None)
             self.set_feerounding_visibility(False)
-            self.warning = ''
+            self.messages = []
         else:
-            self.check_warnings()
+            self.messages = self.get_messages()
             self.update_fee_fields()
             if self.locktime_e.get_locktime() is None:
                 self.locktime_e.set_locktime(self.tx.locktime)
@@ -551,11 +547,10 @@ class TxEditor(WindowModalDialog):
 
         self._update_send_button()
         self._update_message()
-        self._update_warning()
 
-    def check_warnings(self):
+    def get_messages(self):
-        # side effects: self.error, self.warning
+        # side effect: self.error
-        warnings = []
+        messages = []
         fee = self.tx.get_fee()
         assert fee is not None
         amount = self.tx.output_value() if self.output_value == '!' else self.output_value
@@ -567,19 +562,19 @@ class TxEditor(WindowModalDialog):
             if not allow_send:
                 self.error = long_warning
             else:
-                warnings.append(long_warning)
+                messages.append(long_warning)
         # warn if spending unconf
         if any((txin.block_height is not None and txin.block_height<=0) for txin in self.tx.inputs()):
-            warnings.append(_('This transaction will spend unconfirmed coins.'))
+            messages.append(_('This transaction will spend unconfirmed coins.'))
         # warn if we merge from mempool
         if self.tx.rbf_merge_txid:
-            warnings.append(_('This payment will be merged with another existing transaction.'))
+            messages.append(_('This payment will be merged with another existing transaction.'))
         # warn if we use multiple change outputs
         num_change = sum(int(o.is_change) for o in self.tx.outputs())
         if num_change > 1:
-            warnings.append(_('This transaction has {} change outputs.'.format(num_change)))
+            messages.append(_('This transaction has {} change outputs.'.format(num_change)))
         # TODO: warn if we send change back to input address
-        self.warning = _('Warning') + ': ' + '\n'.join(warnings) if warnings else ''
+        return messages
 
     def set_locktime(self):
         if not self.tx:
@@ -595,14 +590,10 @@ class TxEditor(WindowModalDialog):
         pass
 
     def _update_message(self):
-        style = ColorScheme.BLUE
-        self.message_label.setStyleSheet(style.as_stylesheet())
-        self.message_label.setText(self.message)
-
-    def _update_warning(self):
         style = ColorScheme.RED if self.error else ColorScheme.BLUE
-        self.warning_label.setStyleSheet(style.as_stylesheet())
+        message_str = '\n'.join(self.messages) if self.messages else ''
-        self.warning_label.setText(self.error or self.warning)
+        self.message_label.setStyleSheet(style.as_stylesheet())
+        self.message_label.setText(self.error or message_str)
 
     def _update_send_button(self):
         enabled = bool(self.tx) and not self.error
@@ -645,8 +636,6 @@ class ConfirmTxDialog(TxEditor):
             self.tx = self.make_tx(fee_estimator, confirmed_only=confirmed_only)
             self.not_enough_funds = False
             self.no_dynfee_estimates = False
-            error = ''
-            message = ''
         except NotEnoughFunds:
             self.not_enough_funds = True
             self.tx = None

electrum/gui/qt/rbf_dialog.py

@@ -126,14 +126,18 @@ class _BaseRBFDialog(TxEditor):
             except CannotBumpFee as e:
                 self.tx = None
                 self.error = str(e)
+
+    def get_messages(self):
+        messages = super().get_messages()
         if not self.tx:
             return
         delta = self.tx.get_fee() - self.old_tx.get_fee()
         if not self.is_decrease_payment():
-            self.message = _("You will pay {} more.").format(self.main_window.format_amount_and_units(delta))
+            msg = _("You will pay {} more.").format(self.main_window.format_amount_and_units(delta))
         else:
-            self.message = _("The recipient will receive {} less.").format(self.main_window.format_amount_and_units(delta))
+            msg = _("The recipient will receive {} less.").format(self.main_window.format_amount_and_units(delta))
-
+        messages.insert(0, msg)
+        return messages
 
 
 class BumpFeeDialog(_BaseRBFDialog):