Add unit tests for QgsProcessingUtils::mapLayerFromString

Author: nyalldawson

python/core/processing/qgsprocessingutils.sip

@@ -68,9 +68,11 @@ class QgsProcessingUtils
 
     static QgsMapLayer *mapLayerFromString( const QString &string, QgsProcessingContext &context, bool allowLoadingNewLayers = true );
 %Docstring
- Interprets a string as a map layer within the supplied ``context``. The method will attempt to
+ Interprets a string as a map layer within the supplied ``context``.
+
+ The method will attempt to
  load a layer matching the passed ``string``. E.g. if the string matches a layer ID or name
- within the current project this layer will be returned.
+ within the context's project or temporary layer store then this layer will be returned.
  If the string is a file path and ``allowLoadingNewLayers`` is true, then the layer at this
  file path will be loaded and added to the context's temporary layer store.
  Ownership of the layer remains with the ``context`` or the context's current project.

src/core/processing/qgsprocessingutils.h

@@ -80,9 +80,11 @@ class CORE_EXPORT QgsProcessingUtils
     static QList< QgsMapLayer * > compatibleLayers( QgsProject *project, bool sort = true );
 
     /**
-     * Interprets a string as a map layer within the supplied \a context. The method will attempt to
+     * Interprets a string as a map layer within the supplied \a context.
+     *
+     * The method will attempt to
      * load a layer matching the passed \a string. E.g. if the string matches a layer ID or name
-     * within the current project this layer will be returned.
+     * within the context's project or temporary layer store then this layer will be returned.
      * If the string is a file path and \a allowLoadingNewLayers is true, then the layer at this
      * file path will be loaded and added to the context's temporary layer store.
      * Ownership of the layer remains with the \a context or the context's current project.

tests/src/core/testqgsprocessing.cpp

@@ -104,6 +104,7 @@ class TestQgsProcessing: public QObject
     void removeProvider();
     void compatibleLayers();
     void normalizeLayerSource();
+    void mapLayers();
     void mapLayerFromString();
     void algorithm();
     void features();
@@ -331,7 +332,7 @@ void TestQgsProcessing::normalizeLayerSource()
   QCOMPARE( QgsProcessingUtils::normalizeLayerSource( "data\\layers \"new\"\\test.shp" ), QString( "data/layers 'new'/test.shp" ) );
 }
 
-void TestQgsProcessing::mapLayerFromString()
+void TestQgsProcessing::mapLayers()
 {
   // test mapLayerFromProject
 
@@ -364,7 +365,7 @@ void TestQgsProcessing::mapLayerFromString()
   QCOMPARE( QgsProcessingUtils::mapLayerFromProject( r1->id(), &p ), r1 );
   QCOMPARE( QgsProcessingUtils::mapLayerFromProject( v1->id(), &p ), v1 );
 
-  // test mapLayerFromString
+  // test loadMapLayerFromString
   QgsMapLayer *l = QgsProcessingUtils::loadMapLayerFromString( raster2 );
   QVERIFY( l->isValid() );
   QCOMPARE( l->type(), QgsMapLayer::RasterLayer );
@@ -379,6 +380,71 @@ void TestQgsProcessing::mapLayerFromString()
   delete l;
 }
 
+void TestQgsProcessing::mapLayerFromString()
+{
+  // test mapLayerFromString
+
+  QgsProcessingContext c;
+  QgsProject p;
+
+  // add a bunch of layers to a project
+  QString testDataDir = QStringLiteral( TEST_DATA_DIR ) + '/'; //defined in CmakeLists.txt
+  QString raster1 = testDataDir + "tenbytenraster.asc";
+  QString raster2 = testDataDir + "landsat.tif";
+  QFileInfo fi1( raster1 );
+  QgsRasterLayer *r1 = new QgsRasterLayer( fi1.filePath(), "R1" );
+  QVERIFY( r1->isValid() );
+  QFileInfo fi2( raster2 );
+  QgsRasterLayer *r2 = new QgsRasterLayer( fi2.filePath(), "ar2" );
+  QVERIFY( r2->isValid() );
+
+  QgsVectorLayer *v1 = new QgsVectorLayer( "Polygon", "V4", "memory" );
+  QgsVectorLayer *v2 = new QgsVectorLayer( "Point", "v1", "memory" );
+  p.addMapLayers( QList<QgsMapLayer *>() << r1 << r2 << v1 << v2 );
+
+  // no project set yet
+  QVERIFY( ! QgsProcessingUtils::mapLayerFromString( QString(), c ) );
+  QVERIFY( ! QgsProcessingUtils::mapLayerFromString( QStringLiteral( "v1" ), c ) );
+
+  c.setProject( &p );
+
+  // layers from current project
+  QVERIFY( ! QgsProcessingUtils::mapLayerFromString( QString(), c ) );
+  QCOMPARE( QgsProcessingUtils::mapLayerFromString( raster1, c ), r1 );
+  QCOMPARE( QgsProcessingUtils::mapLayerFromString( raster2, c ), r2 );
+  QCOMPARE( QgsProcessingUtils::mapLayerFromString( "R1", c ), r1 );
+  QCOMPARE( QgsProcessingUtils::mapLayerFromString( "ar2", c ), r2 );
+  QCOMPARE( QgsProcessingUtils::mapLayerFromString( "V4", c ), v1 );
+  QCOMPARE( QgsProcessingUtils::mapLayerFromString( "v1", c ), v2 );
+  QCOMPARE( QgsProcessingUtils::mapLayerFromString( r1->id(), c ), r1 );
+  QCOMPARE( QgsProcessingUtils::mapLayerFromString( v1->id(), c ), v1 );
+
+  // check that layers in context temporary store are used
+  QgsVectorLayer *v5 = new QgsVectorLayer( "Polygon", "V5", "memory" );
+  QgsVectorLayer *v6 = new QgsVectorLayer( "Point", "v6", "memory" );
+  c.temporaryLayerStore().addMapLayers( QList<QgsMapLayer *>() << v5 << v6 );
+  QCOMPARE( QgsProcessingUtils::mapLayerFromString( "V5", c ), v5 );
+  QCOMPARE( QgsProcessingUtils::mapLayerFromString( "v6", c ), v6 );
+  QCOMPARE( QgsProcessingUtils::mapLayerFromString( v5->id(), c ), v5 );
+  QCOMPARE( QgsProcessingUtils::mapLayerFromString( v6->id(), c ), v6 );
+  QVERIFY( ! QgsProcessingUtils::mapLayerFromString( "aaaaa", c ) );
+
+  // if specified, check that layers can be loaded
+  QVERIFY( ! QgsProcessingUtils::mapLayerFromString( "aaaaa", c ) );
+  QString newRaster = testDataDir + "requires_warped_vrt.tif";
+  // don't allow loading
+  QVERIFY( ! QgsProcessingUtils::mapLayerFromString( newRaster, c, false ) );
+  // allow loading
+  QgsMapLayer *loadedLayer = QgsProcessingUtils::mapLayerFromString( newRaster, c, true );
+  QVERIFY( loadedLayer->isValid() );
+  QCOMPARE( loadedLayer->type(), QgsMapLayer::RasterLayer );
+  // should now be in temporary store
+  QCOMPARE( c.temporaryLayerStore().mapLayer( loadedLayer->id() ), loadedLayer );
+
+  // since it's now in temporary store, should be accessible even if we deny loading new layers
+  QCOMPARE( QgsProcessingUtils::mapLayerFromString( newRaster, c, false ), loadedLayer );
+}
+
 void TestQgsProcessing::algorithm()
 {
   DummyAlgorithm alg( "test" );