wizard: some fixes

related: #5174

electrum/base_wizard.py

@@ -299,7 +299,8 @@ class BaseWizard(object):
                 _('Debug message') + '\n',
                 debug_msg
             ])
-            self.confirm_dialog(title=title, message=msg, run_next= lambda x: self.choose_hw_device(purpose))
+            self.confirm_dialog(title=title, message=msg,
+                                run_next=lambda x: self.choose_hw_device(purpose, storage=storage))
             return
         # select device
         self.devices = devices
@@ -326,15 +327,15 @@ class BaseWizard(object):
                             + _('Please try again.'))
             devmgr = self.plugins.device_manager
             devmgr.unpair_id(device_info.device.id_)
-            self.choose_hw_device(purpose)
+            self.choose_hw_device(purpose, storage=storage)
             return
         except (UserCancelled, GoBack):
-            self.choose_hw_device(purpose)
+            self.choose_hw_device(purpose, storage=storage)
             return
         except BaseException as e:
             traceback.print_exc(file=sys.stderr)
             self.show_error(str(e))
-            self.choose_hw_device(purpose)
+            self.choose_hw_device(purpose, storage=storage)
             return
         if purpose == HWD_SETUP_NEW_WALLET:
             def f(derivation, script_type):

electrum/gui/qt/__init__.py

@@ -28,6 +28,7 @@ import signal
 import sys
 import traceback
 import threading
+from typing import Optional
 
 
 try:
@@ -46,9 +47,9 @@ from electrum.plugin import run_hook
 from electrum.base_wizard import GoBack
 from electrum.util import (UserCancelled, PrintError, profiler,
                            WalletFileException, BitcoinException, get_new_wallet_name)
-from electrum.wallet import Wallet
+from electrum.wallet import Wallet, Abstract_Wallet
 
-from .installwizard import InstallWizard
+from .installwizard import InstallWizard, WalletAlreadyOpenInMemory
 
 
 from .util import get_default_language, read_QIcon, ColorScheme
@@ -191,7 +192,7 @@ class ElectrumGui(PrintError):
                                 self.network_updated_signal_obj)
         self.nd.show()
 
-    def create_window_for_wallet(self, wallet):
+    def _create_window_for_wallet(self, wallet):
         w = ElectrumWindow(self, wallet)
         self.windows.append(w)
         self.build_tray_menu()
@@ -212,9 +213,10 @@ class ElectrumGui(PrintError):
         return wrapper
 
     @count_wizards_in_progress
-    def start_new_window(self, path, uri, app_is_starting=False):
+    def start_new_window(self, path, uri, *, app_is_starting=False):
         '''Raises the window for the wallet if it is open.  Otherwise
         opens the wallet and creates a new window for it'''
+        wallet = None
         try:
             wallet = self.daemon.load_wallet(path, None)
         except BaseException as e:
@@ -222,49 +224,20 @@ class ElectrumGui(PrintError):
             d = QMessageBox(QMessageBox.Warning, _('Error'),
                             _('Cannot load wallet') + ' (1):\n' + str(e))
             d.exec_()
-            if app_is_starting:
-                # do not return so that the wizard can appear
-                wallet = None
-            else:
+            # if app is starting, still let wizard to appear
+            if not app_is_starting:
                 return
         if not wallet:
-            wizard = InstallWizard(self.config, self.app, self.plugins)
-            storage = None
-            try:
-                path, storage = wizard.select_storage(path, self.daemon.get_wallet)
-                # storage is None if file does not exist
-                if storage is None:
-                    wizard.path = path # needed by trustedcoin plugin
-                    wizard.run('new')
-                    storage = wizard.create_storage(path)
-                else:
-                    wizard.run_upgrades(storage)
-            except UserCancelled:
-                return
-            except GoBack as e:
-                self.print_error('[start_new_window] Exception caught (GoBack)', e)
-            except (WalletFileException, BitcoinException) as e:
-                traceback.print_exc(file=sys.stderr)
-                d = QMessageBox(QMessageBox.Warning, _('Error'),
-                                _('Cannot load wallet') + ' (2):\n' + str(e))
-                d.exec_()
-                return
-            finally:
-                wizard.terminate()
-            # return if wallet creation is not complete
-            if storage is None or storage.get_action():
-                return
-            wallet = Wallet(storage)
-            if not self.daemon.get_wallet(wallet.storage.path):
-                # wallet was not in memory
-                wallet.start_network(self.daemon.network)
-                self.daemon.add_wallet(wallet)
+            wallet = self._start_wizard_to_select_or_create_wallet(path)
+        if not wallet:
+            return
+        # create or raise window
         try:
             for w in self.windows:
                 if w.wallet.storage.path == wallet.storage.path:
                     break
             else:
-                w = self.create_window_for_wallet(wallet)
+                w = self._create_window_for_wallet(wallet)
         except BaseException as e:
             traceback.print_exc(file=sys.stdout)
             d = QMessageBox(QMessageBox.Warning, _('Error'),
@@ -284,6 +257,37 @@ class ElectrumGui(PrintError):
         w.activateWindow()
         return w
 
+    def _start_wizard_to_select_or_create_wallet(self, path) -> Optional[Abstract_Wallet]:
+        wizard = InstallWizard(self.config, self.app, self.plugins)
+        try:
+            path, storage = wizard.select_storage(path, self.daemon.get_wallet)
+            # storage is None if file does not exist
+            if storage is None:
+                wizard.path = path  # needed by trustedcoin plugin
+                wizard.run('new')
+                storage = wizard.create_storage(path)
+            else:
+                wizard.run_upgrades(storage)
+        except (UserCancelled, GoBack):
+            return
+        except WalletAlreadyOpenInMemory as e:
+            return e.wallet
+        except (WalletFileException, BitcoinException) as e:
+            traceback.print_exc(file=sys.stderr)
+            d = QMessageBox(QMessageBox.Warning, _('Error'),
+                            _('Cannot load wallet') + ' (2):\n' + str(e))
+            d.exec_()
+            return
+        finally:
+            wizard.terminate()
+        # return if wallet creation is not complete
+        if storage is None or storage.get_action():
+            return
+        wallet = Wallet(storage)
+        wallet.start_network(self.daemon.network)
+        self.daemon.add_wallet(wallet)
+        return wallet
+
     def close_window(self, window):
         if window in self.windows:
            self.windows.remove(window)

electrum/gui/qt/installwizard.py

@@ -6,7 +6,7 @@ import os
 import sys
 import threading
 import traceback
-from typing import Tuple, List, Callable
+from typing import Tuple, List, Callable, NamedTuple, Optional
 
 from PyQt5.QtCore import QRect, QEventLoop, Qt, pyqtSignal
 from PyQt5.QtGui import QPalette, QPen, QPainter, QPixmap
@@ -14,7 +14,7 @@ from PyQt5.QtWidgets import (QWidget, QDialog, QLabel, QHBoxLayout, QMessageBox,
                              QVBoxLayout, QLineEdit, QFileDialog, QPushButton,
                              QGridLayout, QSlider, QScrollArea)
 
-from electrum.wallet import Wallet
+from electrum.wallet import Wallet, Abstract_Wallet
 from electrum.storage import WalletStorage
 from electrum.util import UserCancelled, InvalidPassword, WalletFileException
 from electrum.base_wizard import BaseWizard, HWD_SETUP_DECRYPT_WALLET, GoBack
@@ -104,6 +104,11 @@ def wizard_dialog(func):
     return func_wrapper
 
 
+class WalletAlreadyOpenInMemory(Exception):
+    def __init__(self, wallet: Abstract_Wallet):
+        super().__init__()
+        self.wallet = wallet
+
 
 # WindowModalDialog must come first as it overrides show_error
 class InstallWizard(QDialog, MessageBoxMixin, BaseWizard):
@@ -162,7 +167,7 @@ class InstallWizard(QDialog, MessageBoxMixin, BaseWizard):
         self.raise_()
         self.refresh_gui()  # Need for QT on MacOSX.  Lame.
 
-    def select_storage(self, path, get_wallet_from_daemon):
+    def select_storage(self, path, get_wallet_from_daemon) -> Tuple[str, Optional[WalletStorage]]:
 
         vbox = QVBoxLayout()
         hbox = QHBoxLayout()
@@ -254,7 +259,7 @@ class InstallWizard(QDialog, MessageBoxMixin, BaseWizard):
                 break
             wallet_from_memory = get_wallet_from_daemon(self.temp_storage.path)
             if wallet_from_memory:
-                return wallet_from_memory
+                raise WalletAlreadyOpenInMemory(wallet_from_memory)
             if self.temp_storage.file_exists() and self.temp_storage.is_encrypted():
                 if self.temp_storage.is_encrypted_with_user_pw():
                     password = self.pw_e.text()
@@ -267,7 +272,7 @@ class InstallWizard(QDialog, MessageBoxMixin, BaseWizard):
                     except BaseException as e:
                         traceback.print_exc(file=sys.stdout)
                         QMessageBox.information(None, _('Error'), str(e))
-                        return
+                        raise UserCancelled()
                 elif self.temp_storage.is_encrypted_with_hw_device():
                     try:
                         self.run('choose_hw_device', HWD_SETUP_DECRYPT_WALLET, storage=self.temp_storage)
@@ -281,11 +286,9 @@ class InstallWizard(QDialog, MessageBoxMixin, BaseWizard):
                     except BaseException as e:
                         traceback.print_exc(file=sys.stdout)
                         QMessageBox.information(None, _('Error'), str(e))
-                        return
-                    if self.temp_storage.is_past_initial_decryption():
-                        break
-                    else:
-                        return
+                        raise UserCancelled()
+                    assert self.temp_storage.is_past_initial_decryption()
+                    break
                 else:
                     raise Exception('Unexpected encryption version')
 

electrum/storage.py

@@ -119,7 +119,10 @@ class WalletStorage(PrintError):
             if encryption is disabled completely (self.is_encrypted() == False),
             or if encryption is enabled but the contents have already been decrypted.
         """
-        return bool(self.db.data)
+        try:
+            return bool(self.db.data)
+        except AttributeError:
+            return False
 
     def is_encrypted(self):
         """Return if storage encryption is currently enabled."""