Allow to edit empty shapefiles

Fixes #38834
qgis · Jan 19, 2021 · 221c3a8 · 221c3a8
1 parent 5b2685d
commit 221c3a8
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Showing 2 changed files with 33 additions and 7 deletions.
diff --git a/src/core/providers/ogr/qgsogrprovider.cpp b/src/core/providers/ogr/qgsogrprovider.cpp
@@ -2982,12 +2982,6 @@ void QgsOgrProvider::computeCapabilities()
       ability |= CreateSpatialIndex;
       ability |= CreateAttributeIndex;
 
-      if ( mAttributeFields.size() == 0 )
-      {
-        QgsMessageLog::logMessage( tr( "Shapefiles without attribute are considered read-only." ), tr( "OGR" ) );
-        ability &= ~( AddFeatures | DeleteFeatures | ChangeAttributeValues | AddAttributes | DeleteAttributes );
-      }
-
       if ( ( ability & ChangeAttributeValues ) == 0 )
       {
         // on readonly shapes OGR reports that it can delete features although it can't RandomWrite

diff --git a/tests/src/python/test_provider_ogr.py b/tests/src/python/test_provider_ogr.py
@@ -19,14 +19,16 @@
 import mockedwebserver
 
 from osgeo import gdal, ogr  # NOQA
-from qgis.PyQt.QtCore import QVariant, QByteArray
+from qgis.PyQt.QtCore import QVariant, QByteArray, QTemporaryDir
 from qgis.core import (
     NULL,
     QgsAuthMethodConfig,
     QgsApplication,
+    QgsCoordinateTransformContext,
     QgsProject,
     QgsField,
     QgsFields,
+    QgsGeometry,
     QgsRectangle,
     QgsProviderRegistry,
     QgsFeature,
@@ -35,6 +37,7 @@
     QgsDataProvider,
     QgsVectorDataProvider,
     QgsVectorLayer,
+    QgsVectorFileWriter,
     QgsWkbTypes,
     QgsNetworkAccessManager
 )
@@ -869,6 +872,35 @@ def testHTTPRequestsOverrider(self):
             with mockedwebserver.install_http_handler(handler):
                 QgsVectorLayer("OAPIF:http://127.0.0.1:%d/collections/foo authcfg='%s'" % (port, config.id()), 'test', 'ogr')
 
+    def testShapefilesWithNoAttributes(self):
+        """Test issue GH #38834"""
+
+        ml = QgsVectorLayer('Point?crs=epsg:4326', 'test', 'memory')
+        self.assertTrue(ml.isValid())
+
+        d = QTemporaryDir()
+        options = QgsVectorFileWriter.SaveVectorOptions()
+        options.driverName = 'ESRI Shapefile'
+        options.layerName = 'writetest'
+        err, _ = QgsVectorFileWriter.writeAsVectorFormatV2(ml, os.path.join(d.path(), 'writetest.shp'), QgsCoordinateTransformContext(), options)
+        self.assertEqual(err, QgsVectorFileWriter.NoError)
+        self.assertTrue(os.path.isfile(os.path.join(d.path(), 'writetest.shp')))
+
+        vl = QgsVectorLayer(os.path.join(d.path(), 'writetest.shp'))
+        self.assertTrue(bool(vl.dataProvider().capabilities() & QgsVectorDataProvider.AddFeatures))
+
+        # Let's try if we can really add features
+        feature = QgsFeature(vl.fields())
+        geom = QgsGeometry.fromWkt('POINT(9 45)')
+        feature.setGeometry(geom)
+        self.assertTrue(vl.startEditing())
+        self.assertTrue(vl.addFeatures([feature]))
+        self.assertTrue(vl.commitChanges())
+        del (vl)
+
+        vl = QgsVectorLayer(os.path.join(d.path(), 'writetest.shp'))
+        self.assertEqual(vl.featureCount(), 1)
+
 
 if __name__ == '__main__':
     unittest.main()