PR: Fixes to make the app work with PySide6

spyder/api/config/mixins.py

@@ -13,6 +13,9 @@
 from typing import Any, Callable, Optional, Union
 import warnings
 
+# Third-party imports
+from qtpy import PYSIDE6
+
 # Local imports
 from spyder.config.manager import CONF
 from spyder.config.types import ConfigurationKey
@@ -239,10 +242,13 @@ def __init__(self):
             section = self.CONF_SECTION if section is None else section
             observed_options = self._configuration_listeners[section]
             for option in observed_options:
-                logger.debug(
-                    f'{self} is observing option "{option}" in section '
-                    f'"{section}"'
-                )
+                # Avoid a crash at startup due to MRO
+                if not PYSIDE6:
+                    logger.debug(
+                        f'{self} is observing option "{option}" in section '
+                        f'"{section}"'
+                    )
+
                 CONF.observe_configuration(self, section, option)
 
     def __del__(self):
@@ -252,6 +258,16 @@ def __del__(self):
     def _gather_observers(self):
         """Gather all the methods decorated with `on_conf_change`."""
         for method_name in dir(self):
+            # Avoid crash at startup due to MRO
+            if PYSIDE6 and method_name in {
+                # PySide seems to require that the class is instantiated to
+                # access this method
+                "painters",
+                # Method is debounced
+                "restart_kernel",
+            }:
+                continue
+
             method = getattr(self, method_name, None)
             if hasattr(method, '_conf_listen'):
                 info = method._conf_listen

spyder/api/widgets/comboboxes.py

@@ -15,7 +15,6 @@
 
 # Third-party imports
 import qstylizer.style
-from qtpy import PYQT5, PYQT6
 from qtpy.QtCore import QSize, Qt, Signal
 from qtpy.QtGui import QColor, QPainter, QFontMetrics
 from qtpy.QtWidgets import (
@@ -256,7 +255,7 @@ def _generate_stylesheet(self):
         return css
 
 
-class SpyderComboBox(QComboBox, _SpyderComboBoxMixin):
+class SpyderComboBox(_SpyderComboBoxMixin, QComboBox):
     """Default combobox widget for Spyder."""
 
     def __init__(self, parent=None, items_elide_mode=None):
@@ -270,11 +269,8 @@ def __init__(self, parent=None, items_elide_mode=None):
         items_elide_mode: Qt.TextElideMode, optional
             Elide mode for the combobox items.
         """
-        if PYQT5 or PYQT6:
-            super().__init__(parent)
-        else:
-            QComboBox.__init__(self, parent)
-            _SpyderComboBoxMixin.__init__(self)
+        QComboBox.__init__(self, parent)
+        _SpyderComboBoxMixin.__init__(self)
 
         self.is_editable = None
         self._is_shown = False
@@ -375,14 +371,11 @@ def __init__(self, parent=None, items_elide_mode=None):
         self.setStyleSheet(self._css.toString())
 
 
-class SpyderFontComboBox(QFontComboBox, _SpyderComboBoxMixin):
+class SpyderFontComboBox(_SpyderComboBoxMixin, QFontComboBox):
 
     def __init__(self, parent=None):
-        if PYQT5 or PYQT6:
-            super().__init__(parent)
-        else:
-            QFontComboBox.__init__(self, parent)
-            _SpyderComboBoxMixin.__init__(self)
+        QFontComboBox.__init__(self, parent)
+        _SpyderComboBoxMixin.__init__(self)
 
         # Avoid font name eliding because it confuses users.
         # Fixes spyder-ide/spyder#22683

spyder/api/widgets/main_container.py

@@ -12,7 +12,7 @@
 status bar widgets or toolbars.
 """
 
-from qtpy import PYQT5, PYQT6
+from qtpy import PYSIDE2
 from qtpy.QtCore import Signal
 from qtpy.QtWidgets import QWidget
 
@@ -113,7 +113,7 @@ class PluginMainContainer(QWidget, SpyderWidgetMixin):
     """
 
     def __init__(self, name, plugin, parent=None):
-        if PYQT5 or PYQT6:
+        if not PYSIDE2:
             super().__init__(parent=parent, class_parent=plugin)
         else:
             QWidget.__init__(self, parent)

spyder/api/widgets/main_widget.py

@@ -17,7 +17,7 @@
 from typing import Optional
 
 # Third party imports
-from qtpy import PYQT5, PYQT6
+from qtpy import PYSIDE2
 from qtpy.QtCore import QByteArray, QSize, Qt, Signal, Slot
 from qtpy.QtGui import QFocusEvent, QIcon
 from qtpy.QtWidgets import (QApplication, QHBoxLayout, QSizePolicy,
@@ -206,7 +206,7 @@ class PluginMainWidget(QWidget, SpyderWidgetMixin):
     """
 
     def __init__(self, name, plugin, parent=None):
-        if PYQT5 or PYQT6:
+        if not PYSIDE2:
             super().__init__(parent=parent, class_parent=plugin)
         else:
             QWidget.__init__(self, parent)

spyder/api/widgets/mixins.py

@@ -672,7 +672,7 @@ class SpyderWidgetMixin(
     # Context name used to store actions, toolbars, toolbuttons and menus
     CONTEXT_NAME = None
 
-    def __init__(self, class_parent=None):
+    def __init__(self, class_parent=None, parent=None):
         for attr in ['CONF_SECTION', 'PLUGIN_NAME']:
             if getattr(self, attr, None) is None:
                 if hasattr(class_parent, attr):

spyder/api/widgets/status.py

@@ -9,7 +9,7 @@
 
 # Third party imports
 import qstylizer.parser
-from qtpy import PYQT5, PYQT6
+from qtpy import PYSIDE2
 from qtpy.QtCore import Qt, QSize, QTimer, Signal
 from qtpy.QtGui import QIcon
 from qtpy.QtWidgets import QHBoxLayout, QLabel, QWidget
@@ -82,7 +82,7 @@ def __init__(self, parent=None, show_icon=True, show_label=True,
         1. To use an icon, you need to redefine the ``get_icon`` method.
         2. To use a label, you need to call ``set_value``.
         """
-        if PYQT5 or PYQT6:
+        if not PYSIDE2:
             super().__init__(parent, class_parent=parent)
         else:
             QWidget.__init__(self, parent)

spyder/app/tests/test_mainwindow.py

@@ -5414,7 +5414,7 @@ def test_goto_find(main_window, qtbot, tmpdir):
     for i in range(5):
         item = file_item.child(i)
         findinfiles.result_browser.setCurrentItem(item)
-        findinfiles.result_browser.activated(item)
+        findinfiles.result_browser.on_item_activated(item)
         cursor = code_editor.textCursor()
         position = (cursor.selectionStart(), cursor.selectionEnd())
         assert position == match_positions[i]

spyder/plugins/completion/api.py

@@ -16,6 +16,7 @@
 from typing import Any, Optional, Tuple, Union
 
 # Third party imports
+from qtpy import PYSIDE6
 from qtpy.QtCore import Signal, QObject, Slot, Qt
 
 # Local imports
@@ -675,6 +676,13 @@ class CompletionConfigurationObserver(SpyderConfigurationObserver):
     def _gather_observers(self):
         """Gather all the methods decorated with `on_conf_change`."""
         for method_name in dir(self):
+            # Avoid crash at startup due to MRO
+            if PYSIDE6 and method_name in {
+                # Method is debounced
+                "interpreter_changed"
+            }:
+                continue
+
             method = getattr(self, method_name, None)
             if hasattr(method, '_conf_listen'):
                 info = method._conf_listen

spyder/plugins/debugger/widgets/breakpoint_table_view.py

@@ -17,7 +17,7 @@
 
 # Third party imports
 import qstylizer.style
-from qtpy import PYQT5, PYQT6
+from qtpy import PYSIDE2
 from qtpy.compat import to_qvariant
 from qtpy.QtCore import QAbstractTableModel, QModelIndex, Qt, Signal
 from qtpy.QtWidgets import QAbstractItemView, QTableView
@@ -175,7 +175,7 @@ class BreakpointTableView(QTableView, SpyderWidgetMixin):
     sig_conditional_breakpoint_requested = Signal()
 
     def __init__(self, parent, data):
-        if PYQT5 or PYQT6:
+        if not PYSIDE2:
             super().__init__(parent, class_parent=parent)
         else:
             QTableView.__init__(self, parent)

spyder/plugins/debugger/widgets/framesbrowser.py

@@ -492,13 +492,13 @@ def __init__(self, parent):
 
         # Signals
         self.header().sectionClicked.connect(self.sort_section)
-        self.itemActivated.connect(self.activated)
-        self.itemClicked.connect(self.activated)
+        self.itemActivated.connect(self.on_item_activated)
+        self.itemClicked.connect(self.on_item_activated)
 
     def set_title(self, title):
         self.setHeaderLabels([title])
 
-    def activated(self, item):
+    def on_item_activated(self, item):
         """Double-click event."""
         itemdata = self.data.get(id(self.currentItem()))
         if itemdata is not None:

spyder/plugins/editor/api/decoration.py

@@ -111,14 +111,23 @@ def __init__(self, cursor_or_bloc_or_doc, start_pos=None, end_pos=None,
         if start_pos is not None:
             self.cursor.setPosition(start_pos)
         if end_pos is not None:
-            self.cursor.setPosition(end_pos, QTextCursor.KeepAnchor)
+            self.cursor.setPosition(end_pos, QTextCursor.MoveMode.KeepAnchor)
         if start_line is not None:
-            self.cursor.movePosition(self.cursor.Start, self.cursor.MoveAnchor)
-            self.cursor.movePosition(self.cursor.Down, self.cursor.MoveAnchor,
-                                     start_line)
+            self.cursor.movePosition(
+                QTextCursor.MoveOperation.Start,
+                QTextCursor.MoveMode.MoveAnchor
+            )
+            self.cursor.movePosition(
+                QTextCursor.MoveOperation.Down,
+                QTextCursor.MoveMode.MoveAnchor,
+                start_line
+            )
         if end_line is not None:
-            self.cursor.movePosition(self.cursor.Down, self.cursor.KeepAnchor,
-                                     end_line - start_line)
+            self.cursor.movePosition(
+                QTextCursor.MoveOperation.Down,
+                QTextCursor.MoveMode.KeepAnchor,
+                end_line - start_line
+            )
         if font is not None:
             self.format.setFont(font)
 
@@ -173,12 +182,14 @@ def select_line(self):
         and stops at the non-whitespace character.
         :return:
         """
-        self.cursor.movePosition(self.cursor.StartOfBlock)
+        self.cursor.movePosition(QTextCursor.MoveOperation.StartOfBlock)
         text = self.cursor.block().text()
         lindent = len(text) - len(text.lstrip())
         self.cursor.setPosition(self.cursor.block().position() + lindent)
-        self.cursor.movePosition(self.cursor.EndOfBlock,
-                                 self.cursor.KeepAnchor)
+        self.cursor.movePosition(
+            QTextCursor.MoveOperation.EndOfBlock,
+            QTextCursor.MoveMode.KeepAnchor
+        )
 
     def set_full_width(self, flag=True, clear=True):
         """