[mypy] don't use implicit optionals

This is explicitely prohibited by PEP 484

electrumabc/address.py

@@ -28,7 +28,7 @@
 import hashlib
 import struct
 from collections import namedtuple
-from typing import Tuple, Union
+from typing import Optional, Tuple, Union
 
 from . import cashaddr, networks
 from .bitcoin import (
@@ -394,7 +394,7 @@ def from_cashaddr_string(
         cls,
         string: str,
         *,
-        net: networks.AbstractNet = None,
+        net: Optional[networks.AbstractNet] = None,
         support_arbitrary_prefix: bool = False,
     ):
         """Construct from a cashaddress string.
@@ -451,7 +451,7 @@ def from_string(
         cls,
         string: str,
         *,
-        net: networks.AbstractNet = None,
+        net: Optional[networks.AbstractNet] = None,
         support_arbitrary_prefix: bool = False,
     ):
         """Construct from an address string.

electrumabc/base_wizard.py

@@ -146,7 +146,7 @@ def do_upgrade():
             do_upgrade, _("Upgrading wallet format..."), on_finished=on_finished
         )
 
-    def run_task_without_blocking_gui(self, task, *, msg: str = None) -> Any:
+    def run_task_without_blocking_gui(self, task, *, msg: Optional[str] = None) -> Any:
         """Perform a task in a thread without blocking the GUI.
         Returns the result of 'task', or raises the same exception.
         This method blocks until 'task' is finished.

electrumabc/bitcoin.py

@@ -1508,13 +1508,13 @@ def __init__(self, enc, *, net=None):
         )
 
     @property
-    def lot(self) -> int:
+    def lot(self) -> Optional[int]:
         """Returns the 'lot' number if 'hasLotSequence' or None otherwise."""
         if self.dec and self.hasLotSequence:
             return self.entropy[4] * 4096 + self.entropy[5] * 16 + self.entropy[6] // 16
 
     @property
-    def sequence(self) -> int:
+    def sequence(self) -> Optional[int]:
         """Returns the 'sequence' number if 'hasLotSequence' or None
         otherwise."""
         if self.dec and self.hasLotSequence:
@@ -1783,7 +1783,7 @@ def encrypt(cls, wif: str, passphrase: str, *, net=None) -> object:
     def createECMult(
         cls,
         passphrase: str,
-        lot_sequence: Tuple[int, int] = None,
+        lot_sequence: Optional[Tuple[int, int]] = None,
         compressed=True,
         *,
         net=None,

electrumabc/contacts.py

@@ -26,7 +26,7 @@
 import re
 import traceback
 from collections import namedtuple
-from typing import List
+from typing import List, Optional
 
 import dns
 from dns.exception import DNSException
@@ -303,7 +303,10 @@ def replace(self, old: Contact, new: Contact):
         return False
 
     def add(
-        self, contact: Contact, replace_old: Contact = None, unique: bool = False
+        self,
+        contact: Contact,
+        replace_old: Optional[Contact] = None,
+        unique: bool = False,
     ) -> bool:
         """Puts a contact in the contact list, appending it at the end.
         Optionally, if replace_old is specified, will replace the entry

electrumabc/plugins.py

@@ -1092,7 +1092,7 @@ def unpaired_device_infos(
         self,
         handler: Optional[HardwareHandlerBase],
         plugin: HW_PluginBase,
-        devices: List[Device] = None,
+        devices: Optional[List[Device]] = None,
     ) -> List["DeviceInfo"]:
         """Returns a list of DeviceInfo objects: one for each connected,
         unpaired device accepted by the plugin."""
@@ -1122,7 +1122,7 @@ def select_device(
         plugin: HW_PluginBase,
         handler: HardwareHandlerBase,
         keystore: Hardware_KeyStore,
-        devices: List["Device"] = None,
+        devices: Optional[List["Device"]] = None,
     ) -> DeviceInfo:
         """Ask the user to select a device to use if there is more than one,
         and return the DeviceInfo for the device."""

electrumabc/transaction.py

@@ -26,7 +26,7 @@
 import hashlib
 import struct
 import warnings
-from typing import Tuple, Union
+from typing import Optional, Tuple, Union
 
 import ecdsa
 
@@ -1574,7 +1574,7 @@ def tx_cache_get(cls, txid: str) -> object:
         return None
 
     @classmethod
-    def tx_cache_put(cls, tx: object, txid: str = None):
+    def tx_cache_put(cls, tx: object, txid: Optional[str] = None):
         """Puts a non-deserialized copy of tx into the tx_cache."""
         if not tx or not tx.raw:
             raise ValueError("Please pass a tx which has a valid .raw attribute!")

electrumabc/wallet.py

@@ -2954,12 +2954,12 @@ def rebuild_history(self):
         self.start_threads(network)
         self.network.trigger_callback("wallet_updated", self)
 
-    def is_schnorr_possible(self, reason: list = None) -> bool:
+    def is_schnorr_possible(self, reason: Optional[list] = None) -> bool:
         """Returns True if this wallet type is compatible.
         `reason` is an optional list where you would like a translated string
         of why Schnorr isn't possible placed (on False return)."""
         ok = bool(not self.is_multisig() and not self.is_hardware())
-        if not ok and isinstance(reason, list):
+        if not ok and reason is not None:
             reason.insert(0, _("Schnorr signatures are disabled for this wallet type."))
         return ok
 

electrumabc/winconsole.py

@@ -32,12 +32,13 @@
 import ctypes
 import os
 import sys
+from typing import Iterator, Optional
 
 STD_OUTPUT_HANDLE = -11
 FILE_TYPE_DISK = 1
 
 
-def parent_process_pids() -> int:
+def parent_process_pids() -> Iterator[int]:
     """
     Returns all parent process PIDs, starting with the closest parent
     """
@@ -58,16 +59,15 @@ def get_console_title() -> str:
     b = bytes(1024)
     b_ptr = ctypes.c_char_p(b)
     title = None
-    title_len = ctypes.windll.kernel32.GetConsoleTitleW(
-        b_ptr, len(b) // 2
-    )  # GetConsoleTitleW expects size in 2-byte chars
+    # GetConsoleTitleW expects size in 2-byte chars
+    title_len = ctypes.windll.kernel32.GetConsoleTitleW(b_ptr, len(b) // 2)  # type: ignore[attr-defined]
     if title_len > 0:
         title = b.decode("utf-16")[:title_len]
     return title
 
 
 def create_or_attach_console(
-    *, attach: bool = True, create: bool = False, title: str = None
+    *, attach: bool = True, create: bool = False, title: Optional[str] = None
 ) -> bool:
     """
     Workaround to the fact that cmd.exe based execution of this program means
@@ -90,8 +90,7 @@ def create_or_attach_console(
     (sys.stdout, sys.stderr) to this found and/or created console.
 
     Always return True on success or if there was a console already,
-    False or None on failure (a None return indicates a missing lib or some
-    other unspecified exception was raised when attempting to create a console).
+    False on failure.
     """
     std_out_handle = ctypes.windll.kernel32.GetStdHandle(STD_OUTPUT_HANDLE)
 
@@ -111,7 +110,7 @@ def create_or_attach_console(
                     break
     except ImportError:
         # User's system lacks psutil
-        return  # Return None in case caller wants to differntiate exceptional failures from regular False return
+        return False
 
     created = False
 
@@ -134,12 +133,11 @@ def create_or_attach_console(
     except OSError:
         # If we get here, we likely were in MinGW / MSYS where CONOUT$ / CONIN$
         # are not valid files or some other weirdness occurred. Give up.
-        return  # return None to indicate underlying exception
+        return False
 
     if title:
-        old_title = (
-            get_console_title() if not created else None
-        )  # save the old title only if not created by us
+        # save the old title only if not created by us
+        old_title = get_console_title() if not created else None
         # Set the console title, if specified
         ctypes.windll.kernel32.SetConsoleTitleW(title)
         if old_title is not None:

electrumabc_gui/qt/avalanche/proof_editor.py

@@ -79,7 +79,7 @@ def __init__(
         self,
         wallet: Deterministic_Wallet,
         receive_address: Optional[Address] = None,
-        parent: QtWidgets.QWidget = None,
+        parent: Optional[QtWidgets.QWidget] = None,
     ):
         CachedWalletPasswordWidget.__init__(self, wallet, parent=parent)
         # This is enough width to show a whole compressed pubkey.

electrumabc_gui/qt/avalanche/util.py

@@ -42,7 +42,7 @@ def __init__(
         self,
         wallet: Deterministic_Wallet,
         pwd: Optional[str] = None,
-        parent: QtWidgets.QWidget = None,
+        parent: Optional[QtWidgets.QWidget] = None,
     ):
         super().__init__(parent)
         self._pwd = pwd
@@ -168,7 +168,7 @@ def __init__(
         self,
         wallet: Deterministic_Wallet,
         pwd: Optional[str] = None,
-        parent: QtWidgets.QWidget = None,
+        parent: Optional[QtWidgets.QWidget] = None,
         additional_info: Optional[str] = None,
     ):
         super().__init__(parent)

electrumabc_gui/qt/main_window.py

@@ -3447,7 +3447,7 @@ def change_password_dialog(self):
         self.status_bar.update_lock_icon(self.wallet.has_password())
 
     def get_passphrase_dialog(
-        self, msg: str, title: str = None, *, permit_empty=False
+        self, msg: str, title: Optional[str] = None, *, permit_empty=False
     ) -> str:
         d = PassphraseDialog(
             self.wallet, self.top_level_window(), msg, title, permit_empty=permit_empty

electrumabc_gui/qt/qrreader/crop_blur_effect.py

@@ -23,6 +23,7 @@
 # ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 # CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
+from typing import Optional
 
 from PyQt5 import QtWidgets
 from PyQt5.QtCore import QObject, QPoint, QRect, Qt
@@ -36,12 +37,12 @@ class QrReaderCropBlurEffect(QtWidgets.QGraphicsBlurEffect):
     BLUR_DARKEN = 0.25
     BLUR_RADIUS = 8
 
-    def __init__(self, parent: QObject, crop: QRect = None):
+    def __init__(self, parent: QObject, crop: Optional[QRect] = None):
         super().__init__(parent)
         self.crop = crop
         self.setBlurRadius(self.BLUR_RADIUS)
 
-    def setCrop(self, crop: QRect = None):
+    def setCrop(self, crop: Optional[QRect] = None):
         self.crop = crop
 
     def draw(self, painter: QPainter):

electrumabc_gui/qt/qrreader/video_overlay.py

@@ -24,7 +24,7 @@
 # CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
-from typing import List
+from typing import List, Optional
 
 from PyQt5 import QtWidgets
 from PyQt5.QtCore import QPoint, QRect, QRectF, QSize, Qt
@@ -48,7 +48,7 @@ class QrReaderVideoOverlay(QtWidgets.QWidget):
     QR_FINDER_OPACITY = 0.25
     QR_FINDER_SIZE = 0.5
 
-    def __init__(self, parent: QtWidgets.QWidget = None):
+    def __init__(self, parent: Optional[QtWidgets.QWidget] = None):
         super().__init__(parent)
 
         self.results = []

electrumabc_gui/qt/qrreader/video_surface.py

@@ -24,7 +24,7 @@
 # CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
-from typing import List
+from typing import List, Optional
 
 from PyQt5.QtCore import QObject, pyqtSignal
 from PyQt5.QtGui import QImage
@@ -45,7 +45,7 @@ class QrReaderVideoSurface(QAbstractVideoSurface):
     necessary and sends them to listeners via the frame_available event.
     """
 
-    def __init__(self, parent: QObject = None):
+    def __init__(self, parent: Optional[QObject] = None):
         super().__init__(parent)
 
     def present(self, frame: QVideoFrame) -> bool:

electrumabc_gui/qt/qrreader/video_widget.py

@@ -23,6 +23,7 @@
 # ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 # CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
+from typing import Optional
 
 from PyQt5 import QtWidgets
 from PyQt5.QtGui import QPainter, QPaintEvent, QPixmap
@@ -35,7 +36,7 @@ class QrReaderVideoWidget(QtWidgets.QWidget):
 
     USE_BILINEAR_FILTER = True
 
-    def __init__(self, parent: QtWidgets.QWidget = None):
+    def __init__(self, parent: Optional[QtWidgets.QWidget] = None):
         super().__init__(parent)
 
         self.pixmap = None

electrumabc_gui/qt/sign_verify_dialog.py

@@ -33,7 +33,9 @@
 
 
 class CollapsibleSection(QWidget):
-    def __init__(self, title: str, content_widget: QWidget, parent: QWidget = None):
+    def __init__(
+        self, title: str, content_widget: QWidget, parent: Optional[QWidget] = None
+    ):
         super().__init__(parent)
 
         main_layout = QGridLayout(self)

electrumabc_gui/qt/style_patcher.py

@@ -2,6 +2,7 @@
 This is used to patch the QApplication style sheet.
 It reads the current stylesheet, appends our modifications and sets the new stylesheet.
 """
+from typing import Optional
 
 from PyQt5 import QtWidgets
 
@@ -37,7 +38,7 @@
 """
 
 
-def patch(use_dark_theme: bool = False, darkstyle_ver: tuple = None):
+def patch(use_dark_theme: bool = False, darkstyle_ver: Optional[tuple] = None):
     if not use_dark_theme:
         return
     custom_patch = ""

electrumabc_gui/qt/util.py

@@ -9,6 +9,7 @@
 from collections import namedtuple
 from functools import partial, wraps
 from locale import atof
+from typing import Optional
 
 from PyQt5 import QtWidgets
 from PyQt5.QtCore import QObject, Qt, QThread, QTimer, pyqtSignal
@@ -980,7 +981,7 @@ def _updateOverlayPos(self):
             x -= scrollbar_width
         self.overlay_widget.move(x, y)
 
-    def addWidget(self, widget: QtWidgets.QWidget, index: int = None):
+    def addWidget(self, widget: QtWidgets.QWidget, index: Optional[int] = None):
         if index is not None:
             self.overlay_layout.insertWidget(index, widget)
         else:
@@ -991,9 +992,9 @@ def addButton(
         icon_name: str,
         on_click,
         tooltip: str,
-        index: int = None,
+        index: Optional[int] = None,
         *,
-        text: str = None,
+        text: Optional[str] = None,
     ) -> QtWidgets.QAbstractButton:
         """icon_name may be None but then you must define text (which is
         hopefully then some nice Unicode character). Both cannot be None.
@@ -1540,7 +1541,7 @@ class TextBrowserKeyboardFocusFilter(QtWidgets.QTextBrowser):
     deactivate keyboard text selection.
     """
 
-    def __init__(self, parent: QtWidgets.QWidget = None):
+    def __init__(self, parent: Optional[QtWidgets.QWidget] = None):
         super().__init__(parent)
 
     def focusInEvent(self, e: QFocusEvent):

electrumabc_gui/qt/utils/aspect_layout.py

@@ -24,14 +24,16 @@
 # CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
-from typing import List
+from typing import List, Optional
 
 from PyQt5 import QtWidgets
 from PyQt5.QtCore import QPoint, QRect, QSize, Qt
 
 
 class FixedAspectRatioLayout(QtWidgets.QLayout):
-    def __init__(self, parent: QtWidgets.QWidget = None, aspect_ratio: float = 1.0):
+    def __init__(
+        self, parent: Optional[QtWidgets.QWidget] = None, aspect_ratio: float = 1.0
+    ):
         super().__init__(parent)
         self.aspect_ratio = aspect_ratio
         self.items: List[QtWidgets.QLayoutItem] = []