Rename UseSelection -> UseSelectionIfPresent, clarify docs

Author: nyalldawson

python/core/processing/qgsprocessingcontext.sip

@@ -28,7 +28,7 @@ class QgsProcessingContext
 
     enum Flag
     {
-      UseSelection,
+      UseSelectionIfPresent,
     };
     typedef QFlags<QgsProcessingContext::Flag> Flags;
 

python/plugins/processing/tests/ToolsTest.py

@@ -86,7 +86,7 @@ def testValues(self):
         self.assertEqual(res[2], [2, 1, 0, 2, 1, 0, 0, 0, 0])
 
         # test with selected features
-        context.setFlags(QgsProcessingContext.UseSelection)
+        context.setFlags(QgsProcessingContext.UseSelectionIfPresent)
         test_layer.selectByIds([2, 4, 6])
         res = vector.values(test_layer, context, 1)
         self.assertEqual(set(res[1]), set([5, 7, 3]))
@@ -111,7 +111,7 @@ def testUniqueValues(self):
         self.assertEqual(set(v), set([2, 1, 0]))
 
         # test with selected features
-        context.setFlags(QgsProcessingContext.UseSelection)
+        context.setFlags(QgsProcessingContext.UseSelectionIfPresent)
         test_layer.selectByIds([2, 4, 6])
         v = vector.uniqueValues(test_layer, context, 'id')
         self.assertEqual(len(v), len(set(v)))

python/plugins/processing/tools/general.py

@@ -108,7 +108,7 @@ def createContext():
 
     use_selection = ProcessingConfig.getSetting(ProcessingConfig.USE_SELECTED)
     if use_selection:
-        context.setFlags(QgsProcessingContext.UseSelection)
+        context.setFlags(QgsProcessingContext.UseSelectionIfPresent)
 
     invalid_features_method = ProcessingConfig.getSetting(ProcessingConfig.FILTER_INVALID_GEOMETRIES)
     context.setInvalidGeometryCheck(invalid_features_method)

python/plugins/processing/tools/vector.py

@@ -94,7 +94,7 @@ def uniqueValues(layer, context, attribute):
     """
 
     fieldIndex = resolveFieldIndex(layer, attribute)
-    if context.flags() & QgsProcessingContext.UseSelection \
+    if context.flags() & QgsProcessingContext.UseSelectionIfPresent \
             and layer.selectedFeatureCount() > 0:
 
         # iterate through selected features

src/core/processing/qgsprocessingcontext.h

@@ -41,7 +41,7 @@ class CORE_EXPORT QgsProcessingContext
     //! Flags that affect how processing algorithms are run
     enum Flag
     {
-      UseSelection = 1 << 0,  //!< Filter to selected features when running algorithms
+      UseSelectionIfPresent = 1 << 0,  //!< Filter to selected features when running algorithms (if a selection exists)
     };
     Q_DECLARE_FLAGS( Flags, Flag )
 

src/core/processing/qgsprocessingutils.cpp

@@ -175,7 +175,7 @@ QString QgsProcessingUtils::normalizeLayerSource( const QString &source )
 
 QgsFeatureIterator QgsProcessingUtils::getFeatures( QgsVectorLayer *layer, const QgsProcessingContext &context, const QgsFeatureRequest &request )
 {
-  bool useSelection = context.flags() & QgsProcessingContext::UseSelection && layer->selectedFeatureCount() > 0;
+  bool useSelection = context.flags() & QgsProcessingContext::UseSelectionIfPresent && layer->selectedFeatureCount() > 0;
 
   QgsFeatureRequest req( request );
   req.setInvalidGeometryCheck( context.invalidGeometryCheck() );
@@ -192,7 +192,7 @@ QgsFeatureIterator QgsProcessingUtils::getFeatures( QgsVectorLayer *layer, const
 
 long QgsProcessingUtils::featureCount( QgsVectorLayer *layer, const QgsProcessingContext &context )
 {
-  bool useSelection = context.flags() & QgsProcessingContext::UseSelection && layer->selectedFeatureCount() > 0;
+  bool useSelection = context.flags() & QgsProcessingContext::UseSelectionIfPresent && layer->selectedFeatureCount() > 0;
   if ( useSelection )
     return layer->selectedFeatureCount();
   else

tests/src/core/testqgsprocessing.cpp

@@ -465,7 +465,7 @@ void TestQgsProcessing::features()
   QCOMPARE( QgsProcessingUtils::featureCount( layer, context ), 5L );
 
   // test with selected features
-  context.setFlags( QgsProcessingContext::UseSelection );
+  context.setFlags( QgsProcessingContext::UseSelectionIfPresent );
   layer->selectByIds( QgsFeatureIds() << 2 << 4 );
   ids = getIds( QgsProcessingUtils::getFeatures( layer, context ) );
   QCOMPARE( ids, QgsFeatureIds() << 2 << 4 );
@@ -479,7 +479,7 @@ void TestQgsProcessing::features()
   QCOMPARE( QgsProcessingUtils::featureCount( layer, context ), 5L );
 
   // using selected features, but no selection
-  context.setFlags( QgsProcessingContext::UseSelection );
+  context.setFlags( QgsProcessingContext::UseSelectionIfPresent );
   layer->removeSelection();
   ids = getIds( QgsProcessingUtils::getFeatures( layer, context ) );
   QCOMPARE( ids, QgsFeatureIds() << 1 << 2 << 3 << 4 << 5 );
@@ -496,7 +496,7 @@ void TestQgsProcessing::features()
 
 
   //test that feature request is honored when using selections
-  context.setFlags( QgsProcessingContext::UseSelection );
+  context.setFlags( QgsProcessingContext::UseSelectionIfPresent );
   layer->selectByIds( QgsFeatureIds() << 2 << 4 );
   ids = getIds( QgsProcessingUtils::getFeatures( layer, context, QgsFeatureRequest().setFlags( QgsFeatureRequest::NoGeometry ) ) );
   QCOMPARE( ids, QgsFeatureIds() << 2 << 4 );