Start on test

python/core/auto_generated/vectortile/qgsmapboxglstyleconverter.sip.in

@@ -30,8 +30,15 @@ Constructor for QgsMapBoxGlStyleConverter.
 The specified MapBox GL ``style`` configuration will be converted.
 %End
 
+
     ~QgsMapBoxGlStyleConverter();
 
+    QString errorMessage() const;
+%Docstring
+Returns a descriptive error message if an error was encountered during the style conversion,
+or an empty string if no error was encountered.
+%End
+
     QgsVectorTileRenderer *renderer() const /Factory/;
 %Docstring
 Returns a new instance of a vector tile renderer representing the converted style,
@@ -44,6 +51,12 @@ Returns a new instance of a vector tile labeling representing the converted styl
 or ``None`` if the style could not be converted successfully.
 %End
 
+  protected:
+
+    void parseLayers( const QVariantList &layers );
+
+  private:
+    QgsMapBoxGlStyleConverter( const QgsMapBoxGlStyleConverter &other );
 };
 
 /************************************************************************

src/core/vectortile/qgsmapboxglstyleconverter.cpp

@@ -20,11 +20,23 @@
 QgsMapBoxGlStyleConverter::QgsMapBoxGlStyleConverter( const QVariantMap &style )
   : mStyle( style )
 {
-
+  if ( mStyle.contains( QStringLiteral( "layers" ) ) )
+  {
+    parseLayers( mStyle.value( QStringLiteral( "layers" ) ).toList() );
+  }
+  else
+  {
+    mError = QObject::tr( "Could not find layers list in JSON" );
+  }
 }
 
 QgsMapBoxGlStyleConverter::~QgsMapBoxGlStyleConverter() = default;
 
+void QgsMapBoxGlStyleConverter::parseLayers( const QVariantList &layers )
+{
+
+}
+
 QgsVectorTileRenderer *QgsMapBoxGlStyleConverter::renderer() const
 {
   return mRenderer ? mRenderer->clone() : nullptr;

src/core/vectortile/qgsmapboxglstyleconverter.h

@@ -42,8 +42,19 @@ class CORE_EXPORT QgsMapBoxGlStyleConverter
      */
     QgsMapBoxGlStyleConverter( const QVariantMap &style );
 
+    //! QgsMapBoxGlStyleConverter cannot be copied
+    QgsMapBoxGlStyleConverter( const QgsMapBoxGlStyleConverter &other ) = delete;
+    //! QgsMapBoxGlStyleConverter cannot be copied
+    QgsMapBoxGlStyleConverter &operator=( const QgsMapBoxGlStyleConverter &other ) = delete;
+
     ~QgsMapBoxGlStyleConverter();
 
+    /**
+     * Returns a descriptive error message if an error was encountered during the style conversion,
+     * or an empty string if no error was encountered.
+     */
+    QString errorMessage() const { return mError; }
+
     /**
      * Returns a new instance of a vector tile renderer representing the converted style,
      * or NULLPTR if the style could not be converted successfully.
@@ -56,9 +67,20 @@ class CORE_EXPORT QgsMapBoxGlStyleConverter
      */
     QgsVectorTileLabeling *labeling() const SIP_FACTORY;
 
+  protected:
+
+    void parseLayers( const QVariantList &layers );
+
   private:
 
+#ifdef SIP_RUN
+    QgsMapBoxGlStyleConverter( const QgsMapBoxGlStyleConverter &other );
+#endif
+
+
+
     QVariantMap mStyle;
+    QString mError;
 
     std::unique_ptr< QgsVectorTileRenderer > mRenderer;
     std::unique_ptr< QgsVectorTileLabeling > mLabeling;

tests/src/python/CMakeLists.txt

@@ -154,6 +154,7 @@ ADD_PYTHON_TEST(PyQgsLineSymbolLayers test_qgslinesymbollayers.py)
 ADD_PYTHON_TEST(PyQgsLocalDefaultSettings test_qgslocaldefaultsettings.py)
 ADD_PYTHON_TEST(PyQgsLocalizedDataPathRegistry test_qgslocalizeddatapathregistry.py)
 ADD_PYTHON_TEST(PyQgsLocator test_qgslocator.py)
+ADD_PYTHON_TEST(PyQgsMapBoxGlStyleConverter test_qgsmapboxglconverter.py)
 ADD_PYTHON_TEST(PyQgsMapCanvas test_qgsmapcanvas.py)
 ADD_PYTHON_TEST(PyQgsMapCanvasAnnotationItem test_qgsmapcanvasannotationitem.py)
 ADD_PYTHON_TEST(PyQgsMapClippingRegion test_qgsmapclippingregion.py)

tests/src/python/test_qgsmapboxglconverter.py

@@ -0,0 +1,55 @@
+# -*- coding: utf-8 -*-
+"""QGIS Unit tests for QgsMapBoxGlStyleConverter.
+
+.. note:: This program is free software; you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation; either version 2 of the License, or
+(at your option) any later version.
+"""
+__author__ = '(C) 2020 by Nyall Dawson'
+__date__ = '29/07/2020'
+__copyright__ = 'Copyright 2020, The QGIS Project'
+
+import qgis  # NOQA
+
+from qgis.PyQt.QtCore import (QSize,
+                              QDir)
+from qgis.PyQt.QtGui import (QImage,
+                             QPainter,
+                             QColor)
+from qgis.core import (QgsMapBoxGlStyleConverter,
+                       QgsCoordinateTransform,
+                       QgsProject,
+                       QgsPoint,
+                       QgsCoordinateReferenceSystem,
+                       QgsFillSymbol,
+                       QgsRenderChecker,
+                       QgsReadWriteContext,
+                       QgsRenderContext,
+                       QgsAnnotationPolygonItem,
+                       QgsRectangle,
+                       QgsLineString,
+                       QgsPolygon,
+                       QgsCurvePolygon,
+                       QgsCircularString
+                       )
+from qgis.PyQt.QtXml import QDomDocument
+
+from qgis.testing import start_app, unittest
+from utilities import unitTestDataPath
+
+start_app()
+TEST_DATA_DIR = unitTestDataPath()
+
+
+class TestQgsMapBoxGlStyleConverter(unittest.TestCase):
+
+    def testNoLayer(self):
+        c = QgsMapBoxGlStyleConverter({'x': 'y'})
+        self.assertEqual(c.errorMessage(), 'Could not find layers list in JSON')
+        self.assertIsNone(c.renderer())
+        self.assertIsNone(c.labeling())
+
+
+if __name__ == '__main__':
+    unittest.main()