Merge pull request #40321 from elpaso/bugfix-gh40316-filtering-error

elpaso · web-flow · commit 4d26e109a16e · 2020-11-29T16:05:38.000+01:00
Do not silently fail while filtering on exp error
diff --git a/python/gui/auto_generated/attributetable/qgsattributetablefiltermodel.sip.in b/python/gui/auto_generated/attributetable/qgsattributetablefiltermodel.sip.in
@@ -234,6 +234,13 @@ Emitted when the filtering of the features has been done
     void visibleReloaded();
 %Docstring
 Emitted when the the visible features on extend are reloaded (the list is created)
+%End
+
+    void filterError( const QString &errorMessage );
+%Docstring
+Emitted when an error occurred while filtering features
+
+.. versionadded:: 3.18
 %End
 
   protected:
diff --git a/src/gui/attributetable/qgsattributetablefiltermodel.cpp b/src/gui/attributetable/qgsattributetablefiltermodel.cpp
@@ -503,15 +503,20 @@ void QgsAttributeTableFilterModel::filterFeatures()
 
   QgsFeature f;
 
+  // Record the first evaluation error
+  QString error;
+
   while ( featIt.nextFeature( f ) )
   {
     mFilterExpressionContext.setFeature( f );
     if ( mFilterExpression.evaluate( &mFilterExpressionContext ).toInt() != 0 )
       filteredFeatures << f.id();
 
     // check if there were errors during evaluating
-    if ( mFilterExpression.hasEvalError() )
-      break;
+    if ( mFilterExpression.hasEvalError() && error.isEmpty() )
+    {
+      error = mFilterExpression.evalErrorString( );
+    }
   }
 
   featIt.close();
@@ -521,6 +526,12 @@ void QgsAttributeTableFilterModel::filterFeatures()
   QApplication::restoreOverrideCursor();
 
   emit featuresFiltered();
+
+  if ( ! error.isEmpty() )
+  {
+    emit filterError( error );
+  }
+
 }
 
 
diff --git a/src/gui/attributetable/qgsattributetablefiltermodel.h b/src/gui/attributetable/qgsattributetablefiltermodel.h
@@ -258,6 +258,12 @@ class GUI_EXPORT QgsAttributeTableFilterModel: public QSortFilterProxyModel, pub
      */
     void visibleReloaded();
 
+    /**
+     * Emitted when an error occurred while filtering features
+     * \since QGIS 3.18
+     */
+    void filterError( const QString &errorMessage );
+
   protected:
 
     /**
diff --git a/src/gui/attributetable/qgsdualview.cpp b/src/gui/attributetable/qgsdualview.cpp
@@ -44,6 +44,7 @@
 #include "qgsshortcutsmanager.h"
 #include "qgsfieldconditionalformatwidget.h"
 #include "qgsmapcanvasutils.h"
+#include "qgsmessagebar.h"
 
 
 QgsDualView::QgsDualView( QWidget *parent )
@@ -293,6 +294,7 @@ void QgsDualView::setFilterMode( QgsAttributeTableFilterModel::FilterMode filter
     case QgsAttributeTableFilterModel::ShowEdited:
     case QgsAttributeTableFilterModel::ShowFilteredList:
       disconnect( mFilterModel, &QgsAttributeTableFilterModel::featuresFiltered, this, &QgsDualView::filterChanged );
+      disconnect( mFilterModel, &QgsAttributeTableFilterModel::filterError, this, &QgsDualView::filterError );
       break;
 
     case QgsAttributeTableFilterModel::ShowSelected:
@@ -332,6 +334,7 @@ void QgsDualView::setFilterMode( QgsAttributeTableFilterModel::FilterMode filter
     case QgsAttributeTableFilterModel::ShowEdited:
     case QgsAttributeTableFilterModel::ShowFilteredList:
       connect( mFilterModel, &QgsAttributeTableFilterModel::featuresFiltered, this, &QgsDualView::filterChanged );
+      connect( mFilterModel, &QgsAttributeTableFilterModel::filterError, this, &QgsDualView::filterError );
       break;
 
     case QgsAttributeTableFilterModel::ShowSelected:
@@ -599,6 +602,14 @@ void QgsDualView::flashButtonClicked( bool clicked )
     canvas->flashFeatureIds( mLayer, mFeatureListView->currentEditSelection() );
 }
 
+void QgsDualView::filterError( const QString &errorMessage )
+{
+  if ( mEditorContext.mainMessageBar() )
+  {
+    mEditorContext.mainMessageBar()->pushWarning( tr( "An error occurred while filtering features" ), errorMessage );
+  }
+}
+
 void QgsDualView::featureListAboutToChangeEditSelection( bool &ok )
 {
   if ( mLayer->isEditable() && !mAttributeForm->save() )
diff --git a/src/gui/attributetable/qgsdualview.h b/src/gui/attributetable/qgsdualview.h
@@ -388,6 +388,8 @@ class GUI_EXPORT QgsDualView : public QStackedWidget, private Ui::QgsDualViewBas
 
     void flashButtonClicked( bool clicked );
 
+    void filterError( const QString &errorMessage );
+
   private:
 
     /**
