Setting crs for extent group box shouldn't auto check the box

Causes e.g. changing the destination CRS in the save vector
file dialog to accidentally enable the "extent" filter option.

Refs #18977

src/gui/qgsextentgroupbox.cpp

@@ -78,6 +78,7 @@ void QgsExtentGroupBox::setOutputCrs( const QgsCoordinateReferenceSystem &output
 {
   if ( mOutputCrs != outputCrs )
   {
+    bool prevExtentEnabled = isChecked();
     switch ( mExtentState )
     {
       case CurrentExtent:
@@ -116,6 +117,8 @@ void QgsExtentGroupBox::setOutputCrs( const QgsCoordinateReferenceSystem &output
         break;
     }
 
+    if ( !prevExtentEnabled )
+      setChecked( false );
   }
 
 }

tests/src/python/test_qgsextentgroupbox.py

@@ -86,6 +86,15 @@ def test_SettingExtent(self):
 
     def testSetOutputCrs(self):
         w = qgis.gui.QgsExtentGroupBox()
+        w.setCheckable(True)
+
+        # ensure setting output crs doesn't change state of group box
+        w.setChecked(False)
+        w.setOutputCrs(QgsCoordinateReferenceSystem('epsg:4326'))
+        self.assertFalse(w.isChecked())
+        w.setChecked(True)
+        w.setOutputCrs(QgsCoordinateReferenceSystem('epsg:4326'))
+        self.assertTrue(w.isChecked())
 
         w.setOutputCrs(QgsCoordinateReferenceSystem('epsg:4326'))
         w.setCurrentExtent(QgsRectangle(1, 2, 3, 4), QgsCoordinateReferenceSystem('epsg:4326'))