qt: use delegate QTranslator to gettext (as in QML) and include Qt standard lib translations for strings

used by QTextEdit.createStandardContextMenu()

electrum/gui/common_qt/i18n.py

@@ -0,0 +1,17 @@
+from PyQt6.QtCore import QTranslator
+
+from electrum.i18n import _
+
+
+class ElectrumTranslator(QTranslator):
+    """Delegator for Qt translations to gettext"""
+    def __init__(self, parent=None):
+        super().__init__(parent)
+
+        # explicit enumeration of translatable strings from Qt standard library, so these
+        # will be included in the electrum gettext translation template
+        self._strings = [_('&Undo'), _('&Redo'), _('Cu&t'), _('&Copy'), _('&Paste'), _('Select All'),
+                         _('Copy &Link Location')]
+
+    def translate(self, context, source_text: str, disambiguation, n):
+        return _(source_text, context=context)

electrum/gui/qml/__init__.py

@@ -20,14 +20,15 @@ except Exception as e:
         "Error: Could not import PyQt6.QtQml. On Linux systems, "
         "you may try 'sudo apt-get install python3-pyqt6.qtquick'") from e
 
-from PyQt6.QtCore import (Qt, QCoreApplication, QLocale, QTranslator, QTimer, QT_VERSION_STR, PYQT_VERSION_STR)
+from PyQt6.QtCore import (Qt, QCoreApplication, QLocale, QTimer, QT_VERSION_STR, PYQT_VERSION_STR)
 from PyQt6.QtGui import QGuiApplication
 
-from electrum.i18n import _
 from electrum.plugin import run_hook
 from electrum.util import profiler
 from electrum.logging import Logger
 from electrum.gui import BaseElectrumGui
+from electrum.gui.common_qt.i18n import ElectrumTranslator
+
 
 if TYPE_CHECKING:
     from electrum.daemon import Daemon
@@ -37,14 +38,6 @@ if TYPE_CHECKING:
 from .qeapp import ElectrumQmlApplication, Exception_Hook
 
 
-class ElectrumTranslator(QTranslator):
-    def __init__(self, parent=None):
-        super().__init__(parent)
-
-    def translate(self, context, source_text, disambiguation, n):
-        return _(source_text, context=context)
-
-
 class ElectrumGui(BaseElectrumGui, Logger):
     @profiler
     def __init__(self, config: 'SimpleConfig', daemon: 'Daemon', plugins: 'Plugins'):

electrum/gui/qt/__init__.py

@@ -41,6 +41,7 @@ except Exception as e:
 from PyQt6.QtGui import QGuiApplication
 from PyQt6.QtWidgets import QApplication, QSystemTrayIcon, QWidget, QMenu, QMessageBox, QDialog
 from PyQt6.QtCore import QObject, pyqtSignal, QTimer, Qt
+
 import PyQt6.QtCore as QtCore
 
 try:
@@ -72,6 +73,8 @@ from electrum.storage import WalletStorage
 from electrum.wizard import WizardViewState
 from electrum.keystore import load_keystore
 
+from electrum.gui.common_qt.i18n import ElectrumTranslator
+
 from .util import read_QIcon, ColorScheme, custom_message_box, MessageBoxMixin, WWLabel
 from .main_window import ElectrumWindow
 from .network_dialog import NetworkDialog
@@ -110,7 +113,6 @@ class QElectrumApplication(QApplication):
     alias_received_signal = pyqtSignal()
 
 
-
 class ElectrumGui(BaseElectrumGui, Logger):
 
     network_dialog: Optional['NetworkDialog']
@@ -137,6 +139,8 @@ class ElectrumGui(BaseElectrumGui, Logger):
         self.app = QElectrumApplication(sys.argv)
         self.app.installEventFilter(self.efilter)
         self.app.setWindowIcon(read_QIcon("electrum.png"))
+        self.translator = ElectrumTranslator()
+        self.app.installTranslator(self.translator)
         self._cleaned_up = False
         # timer
         self.timer = QTimer(self.app)

electrum/gui/qt/lightning_tx_dialog.py

@@ -41,7 +41,6 @@ if TYPE_CHECKING:
     from .main_window import ElectrumWindow
 
 
-
 class LightningTxDialog(WindowModalDialog):
 
     def __init__(self, parent: 'ElectrumWindow', tx_item: dict):
@@ -68,12 +67,13 @@ class LightningTxDialog(WindowModalDialog):
             fee_msat = tx_item['fee_msat']
             fee_sat = Decimal(fee_msat) / 1000 if fee_msat is not None else None
             fee_str = self.main_window.format_amount_and_units(fee_sat, timestamp=self.timestamp)
-            vbox.addWidget(QLabel(_("Fee") + f": {fee_str}"))
+            vbox.addWidget(QLabel(_("Fee: {}").format(fee_str)))
         time_str = datetime.datetime.fromtimestamp(self.timestamp).isoformat(' ')[:-3]
         vbox.addWidget(QLabel(_("Date") + ": " + time_str))
         self.tx_desc_label = QLabel(_("Description:"))
         vbox.addWidget(self.tx_desc_label)
         self.tx_desc = ButtonsLineEdit(self.label)
+
         def on_edited():
             text = self.tx_desc.text()
             if self.main_window.wallet.set_label(self.payment_hash, text):