Fix feature request containing a filter expression which needs

both geometry and the magic all attributes flag

(cherry picked from commit 33aa63b)

Author: nyalldawson

src/core/qgsvectorlayerfeatureiterator.cpp

@@ -199,6 +199,7 @@ QgsVectorLayerFeatureIterator::QgsVectorLayerFeatureIterator( QgsVectorLayerFeat
 
   if ( mProviderRequest.filterType() == QgsFeatureRequest::FilterExpression )
   {
+    const bool needsGeom = mProviderRequest.filterExpression()->needsGeometry();
     Q_FOREACH ( const QString &field, mProviderRequest.filterExpression()->referencedColumns() )
     {
       int idx = source->mFields.lookupField( field );
@@ -210,6 +211,12 @@ QgsVectorLayerFeatureIterator::QgsVectorLayerFeatureIterator( QgsVectorLayerFeat
         mProviderRequest.disableFilter();
         // can't limit at provider side
         mProviderRequest.setLimit( -1 );
+        if ( needsGeom )
+        {
+          // have to get geometry from provider in order to evaluate expression on client
+          mProviderRequest.setFlags( mProviderRequest.flags() & ~QgsFeatureRequest::NoGeometry );
+        }
+        break;
       }
     }
   }

tests/src/python/featuresourcetestbase.py

@@ -528,6 +528,22 @@ def testRectAndExpression(self):
         for f in self.source.getFeatures():
             self.assertEqual(request.acceptFeature(f), f['pk'] in expected)
 
+    def testGeomAndAllAttributes(self):
+        """
+        Test combination of a filter which requires geometry and all attributes
+        """
+        request = QgsFeatureRequest().setFilterExpression('attribute($currentfeature,\'cnt\')>200 and $x>=-70 and $x<=-60').setSubsetOfAttributes([]).setFlags(QgsFeatureRequest.NoGeometry)
+        result = set([f['pk'] for f in self.source.getFeatures(request)])
+        all_valid = (all(f.isValid() for f in self.source.getFeatures(request)))
+        self.assertEqual(result, {4})
+        self.assertTrue(all_valid)
+
+        request = QgsFeatureRequest().setFilterExpression('attribute($currentfeature,\'cnt\')>200 and $x>=-70 and $x<=-60')
+        result = set([f['pk'] for f in self.source.getFeatures(request)])
+        all_valid = (all(f.isValid() for f in self.source.getFeatures(request)))
+        self.assertEqual(result, {4})
+        self.assertTrue(all_valid)
+
     def testRectAndFids(self):
         """
         Test the combination of a filter rect along with filterfids

tests/src/python/test_provider_wfs.py

@@ -3857,6 +3857,9 @@ def test_NullValues_regression_20961(self):
         self.assertEqual(str(got_f2[1]['elevation']), 'NULL')
         self.assertEqual(str(got_f2[1]['name']), 'sdf')
 
+    def testGeomAndAllAttributes(self):
+        pass # skip this feature source test -- provider is not affected
+
     def testFilteredFeatureRequests(self):
         """Test https://issues.qgis.org/issues/21077 """
 

tests/src/python/test_qgsvectorlayer.py

@@ -66,6 +66,8 @@
 from featuresourcetestbase import FeatureSourceTestCase
 from utilities import unitTestDataPath
 
+TEST_DATA_DIR = unitTestDataPath()
+
 start_app()
 
 
@@ -184,6 +186,25 @@ def dumpEditBuffer(layer):
         print(("%d | %s" % (f.id(), f.geometry().asWkt())))
 
 
+class TestQgsVectorLayerShapefile(unittest.TestCase, FeatureSourceTestCase):
+
+    """
+    Tests a vector layer against the feature source tests, using a real layer source (not a memory layer)
+    """
+    @classmethod
+    def getSource(cls):
+        vl = QgsVectorLayer(os.path.join(TEST_DATA_DIR, 'provider', 'shapefile.shp'), 'test')
+        assert (vl.isValid())
+        return vl
+
+    @classmethod
+    def setUpClass(cls):
+        """Run before all tests"""
+        QgsGui.editorWidgetRegistry().initEditors()
+        # Create test layer for FeatureSourceTestCase
+        cls.source = cls.getSource()
+
+
 class TestQgsVectorLayer(unittest.TestCase, FeatureSourceTestCase):
 
     @classmethod