Add method to set QgsAbstractGeometry for QgsGeometry, add tests

for implicit sharing of QgsGeometry

Author: nyalldawson

python/core/geometry/qgsgeometry.sip

@@ -34,10 +34,11 @@ class QgsGeometry
     /** copy constructor will prompt a deep copy of the object */
     QgsGeometry( const QgsGeometry & );
 
-    /** Creates a geometry from an abstract geometry object.
+    /** Creates a geometry from an abstract geometry object. Ownership of
+     * geom is transferred.
      * @note added in QGIS 2.10
      */
-    QgsGeometry( QgsAbstractGeometryV2* geom );
+    QgsGeometry( QgsAbstractGeometryV2* geom /Transfer/ );
 
     //! Destructor
     ~QgsGeometry();
@@ -47,6 +48,11 @@ class QgsGeometry
      */
     const QgsAbstractGeometryV2* geometry() const;
 
+    /** Sets the underlying geometry store. Ownership of geometry is transferred.
+     * @note added in QGIS 2.10
+     */
+    void setGeometry( QgsAbstractGeometryV2* geometry /Transfer/ );
+
     /** Creates a new geometry from a WKT string */
     static QgsGeometry* fromWkt( QString wkt ) /Factory/;
     /** Creates a new geometry from a QgsPoint object*/

src/core/geometry/qgsgeometry.cpp

@@ -143,6 +143,12 @@ const QgsAbstractGeometryV2* QgsGeometry::geometry() const
   return d->geometry;
 }
 
+void QgsGeometry::setGeometry( QgsAbstractGeometryV2* geometry )
+{
+  detach( false );
+  d->geometry = geometry;
+}
+
 QgsGeometry* QgsGeometry::fromWkt( QString wkt )
 {
   QgsAbstractGeometryV2* geom = QgsGeometryImport::geomFromWkt( wkt );

src/core/geometry/qgsgeometry.h

@@ -80,7 +80,8 @@ class CORE_EXPORT QgsGeometry
       */
     QgsGeometry & operator=( QgsGeometry const & rhs );
 
-    /** Creates a geometry from an abstract geometry object.
+    /** Creates a geometry from an abstract geometry object. Ownership of
+     * geom is transferred.
      * @note added in QGIS 2.10
      */
     QgsGeometry( QgsAbstractGeometryV2* geom );
@@ -93,6 +94,11 @@ class CORE_EXPORT QgsGeometry
      */
     const QgsAbstractGeometryV2* geometry() const;
 
+    /** Sets the underlying geometry store. Ownership of geometry is transferred.
+     * @note added in QGIS 2.10
+     */
+    void setGeometry( QgsAbstractGeometryV2* geometry );
+
     /** Creates a new geometry from a WKT string */
     static QgsGeometry* fromWkt( QString wkt );
     /** Creates a new geometry from a QgsPoint object*/

tests/src/core/testqgsgeometry.cpp

@@ -30,6 +30,7 @@
 #include <qgsapplication.h>
 #include <qgsgeometry.h>
 #include <qgspoint.h>
+#include "qgspointv2.h"
 
 //qgs unit test utility class
 #include "qgsrenderchecker.h"
@@ -50,6 +51,9 @@ class TestQgsGeometry : public QObject
     void init();// will be called before each testfunction is executed.
     void cleanup();// will be called after every testfunction.
 
+    void copy();
+    void assignment();
+
     void fromQgsPoint();
     void fromQPoint();
     void fromQPolygonF();
@@ -207,6 +211,51 @@ void TestQgsGeometry::cleanup()
   delete mpPainter;
 }
 
+void TestQgsGeometry::copy()
+{
+  //create a point geometry
+  QgsGeometry original( new QgsPointV2( 1.0, 2.0 ) );
+  QCOMPARE( original.geometry()->vertexAt( QgsVertexId( 0, 0, 0 ) ).x(), 1.0 );
+  QCOMPARE( original.geometry()->vertexAt( QgsVertexId( 0, 0, 0 ) ).y(), 2.0 );
+
+  //implicitly shared copy
+  QgsGeometry copy( original );
+  QCOMPARE( copy.geometry()->vertexAt( QgsVertexId( 0, 0, 0 ) ).x(), 1.0 );
+  QCOMPARE( copy.geometry()->vertexAt( QgsVertexId( 0, 0, 0 ) ).y(), 2.0 );
+
+  //trigger a detach
+  copy.setGeometry( new QgsPointV2( 3.0, 4.0 ) );
+  QCOMPARE( copy.geometry()->vertexAt( QgsVertexId( 0, 0, 0 ) ).x(), 3.0 );
+  QCOMPARE( copy.geometry()->vertexAt( QgsVertexId( 0, 0, 0 ) ).y(), 4.0 );
+
+  //make sure original was untouched
+  QCOMPARE( original.geometry()->vertexAt( QgsVertexId( 0, 0, 0 ) ).x(), 1.0 );
+  QCOMPARE( original.geometry()->vertexAt( QgsVertexId( 0, 0, 0 ) ).y(), 2.0 );
+}
+
+void TestQgsGeometry::assignment()
+{
+  //create a point geometry
+  QgsGeometry original( new QgsPointV2( 1.0, 2.0 ) );
+  QCOMPARE( original.geometry()->vertexAt( QgsVertexId( 0, 0, 0 ) ).x(), 1.0 );
+  QCOMPARE( original.geometry()->vertexAt( QgsVertexId( 0, 0, 0 ) ).y(), 2.0 );
+
+  //assign to implicitly shared copy
+  QgsGeometry copy;
+  copy = original;
+  QCOMPARE( copy.geometry()->vertexAt( QgsVertexId( 0, 0, 0 ) ).x(), 1.0 );
+  QCOMPARE( copy.geometry()->vertexAt( QgsVertexId( 0, 0, 0 ) ).y(), 2.0 );
+
+  //trigger a detach
+  copy.setGeometry( new QgsPointV2( 3.0, 4.0 ) );
+  QCOMPARE( copy.geometry()->vertexAt( QgsVertexId( 0, 0, 0 ) ).x(), 3.0 );
+  QCOMPARE( copy.geometry()->vertexAt( QgsVertexId( 0, 0, 0 ) ).y(), 4.0 );
+
+  //make sure original was untouched
+  QCOMPARE( original.geometry()->vertexAt( QgsVertexId( 0, 0, 0 ) ).x(), 1.0 );
+  QCOMPARE( original.geometry()->vertexAt( QgsVertexId( 0, 0, 0 ) ).y(), 2.0 );
+}
+
 void TestQgsGeometry::fromQgsPoint()
 {
   QgsPoint point( 1.0, 2.0 );