qt: try even harder not to crash whole app on first start

electrum/gui/qt/__init__.py

@@ -44,7 +44,7 @@ from electrum.plugin import run_hook
 from electrum.storage import WalletStorage
 from electrum.base_wizard import GoBack
 from electrum.util import (UserCancelled, PrintError, profiler,
-                           WalletFileException, BitcoinException)
+                           WalletFileException, BitcoinException, get_new_wallet_name)
 
 from .installwizard import InstallWizard
 
@@ -263,6 +263,10 @@ class ElectrumGui(PrintError):
             d = QMessageBox(QMessageBox.Warning, _('Error'),
                             _('Cannot create window for wallet') + ':\n' + str(e))
             d.exec_()
+            if app_is_starting:
+                wallet_dir = os.path.dirname(path)
+                path = os.path.join(wallet_dir, get_new_wallet_name(wallet_dir))
+                self.start_new_window(path, uri)
             return
         if uri:
             w.pay_to_URI(uri)

electrum/gui/qt/main_window.py

@@ -55,7 +55,8 @@ from electrum.util import (format_time, format_satoshis, format_fee_satoshis,
                            export_meta, import_meta, bh2u, bfh, InvalidPassword,
                            base_units, base_units_list, base_unit_name_to_decimal_point,
                            decimal_point_to_base_unit_name, quantize_feerate,
-                           UnknownBaseUnit, DECIMAL_POINT_DEFAULT, UserFacingException)
+                           UnknownBaseUnit, DECIMAL_POINT_DEFAULT, UserFacingException,
+                           get_new_wallet_name)
 from electrum.transaction import Transaction, TxOutput
 from electrum.address_synchronizer import AddTransactionException
 from electrum.wallet import (Multisig_Wallet, CannotBumpFee, Abstract_Wallet,
@@ -487,13 +488,7 @@ class ElectrumWindow(QMainWindow, MessageBoxMixin, PrintError):
         except FileNotFoundError as e:
             self.show_error(str(e))
             return
-        i = 1
-        while True:
-            filename = "wallet_%d" % i
-            if filename in os.listdir(wallet_folder):
-                i += 1
-            else:
-                break
+        filename = get_new_wallet_name(wallet_folder)
         full_path = os.path.join(wallet_folder, filename)
         self.gui_object.start_new_window(full_path, None)
 

electrum/util.py

@@ -413,6 +413,17 @@ def assert_file_in_datadir_available(path, config_path):
             'Should be at {}'.format(path))
 
 
+def get_new_wallet_name(wallet_folder: str) -> str:
+    i = 1
+    while True:
+        filename = "wallet_%d" % i
+        if filename in os.listdir(wallet_folder):
+            i += 1
+        else:
+            break
+    return filename
+
+
 def assert_bytes(*args):
     """
     porting helper, assert args type