Cleanup message box implementation

Fixes continuous resize loop when clicking show details under sway.
Bloody wayland waste of time

src/calibre/gui2/dialogs/message_box.py

@@ -5,6 +5,7 @@ __license__   = 'GPL v3'
 __copyright__ = '2011, Kovid Goyal <kovid@kovidgoyal.net>'
 __docformat__ = 'restructuredtext en'
 
+from contextlib import suppress
 import sys
 from qt.core import (
     QAction, QApplication, QCheckBox, QDialog, QDialogButtonBox, QGridLayout, QIcon,
@@ -84,7 +85,7 @@ class MessageBox(QDialog):  # {{{
                  add_abort_button=False,
                  only_copy_details=False
     ):
-        QDialog.__init__(self, parent)
+        super().__init__(parent)
         self.only_copy_details = only_copy_details
         self.aborted = False
         if q_icon is None:
@@ -151,18 +152,12 @@ class MessageBox(QDialog):  # {{{
         if not det_msg:
             self.det_msg_toggle.setVisible(False)
 
-        self.resize_needed.connect(self.do_resize, type=Qt.ConnectionType.QueuedConnection)
+        self.resize_needed.connect(self.do_resize)
         self.do_resize()
 
     def on_abort(self):
         self.aborted = True
 
-    def sizeHint(self):
-        ans = QDialog.sizeHint(self)
-        ans.setWidth(max(min(ans.width(), 500), self.bb.sizeHint().width() + 100))
-        ans.setHeight(min(ans.height(), 500))
-        return ans
-
     def toggle_det_msg(self, *args):
         vis = self.det_msg.isVisible()
         self.det_msg.setVisible(not vis)
@@ -170,6 +165,10 @@ class MessageBox(QDialog):  # {{{
         self.resize_needed.emit()
 
     def do_resize(self):
+        sz = self.sizeHint()
+        sz.setWidth(max(min(sz.width(), 500), self.bb.sizeHint().width() + 100))
+        sz.setHeight(min(sz.height(), 500))
+        self.setMaximumSize(sz)
         self.resize(self.sizeHint())
 
     def copy_to_clipboard(self, *args):
@@ -183,11 +182,9 @@ class MessageBox(QDialog):  # {{{
     def showEvent(self, ev):
         ret = QDialog.showEvent(self, ev)
         if self.is_question:
-            try:
+            with suppress(Exception):
                 self.bb.button(QDialogButtonBox.StandardButton.Yes if self.default_yes else QDialogButtonBox.StandardButton.No
                         ).setFocus(Qt.FocusReason.OtherFocusReason)
-            except:
-                pass  # Buttons were changed
         else:
             self.bb.button(QDialogButtonBox.StandardButton.Ok).setFocus(Qt.FocusReason.OtherFocusReason)
         return ret
@@ -494,6 +491,7 @@ class JobError(QDialog):  # {{{
 if __name__ == '__main__':
     from calibre import prepare_string_for_xml
     from calibre.gui2 import Application, question_dialog
+    from qt.core import QMainWindow, QTimer
     app = Application([])
     merged = {'Kovid Goyal': ['Waterloo', 'Doomed'], 'Someone Else': ['Some other book ' * 1000]}
     lines = []
@@ -502,7 +500,12 @@ if __name__ == '__main__':
         for title in sorted(merged[author]):
             lines.append(f'<li>{prepare_string_for_xml(title)}</li>')
         lines.append('</ol>')
-
+    w = QMainWindow()
-    print(question_dialog(None, 'title', 'msg <a href="http://google.com">goog</a> ',
+    w.show()
+    def doit():
+        print(question_dialog(w, 'title', 'msg <a href="http://google.com">goog</a> ',
             det_msg='\n'.join(lines),
             show_copy_button=True))
+        w.close()
+    QTimer.singleShot(100, doit)
+    app.exec()