From 6c392124ca4684c433518a40b81e34200672c77c Mon Sep 17 00:00:00 2001
From: Nyall Dawson <nyall.dawson@gmail.com>
Date: Thu, 18 Jan 2018 15:43:55 +1000
Subject: [PATCH] Fix virtual layers fail if table field names have special
 characters

Fixes #16943
---
 .../virtual/qgsvirtuallayersqlitemodule.cpp   |  2 +-
 tests/src/python/test_provider_virtual.py     | 24 +++++++++++++++++++
 2 files changed, 25 insertions(+), 1 deletion(-)

diff --git a/src/providers/virtual/qgsvirtuallayersqlitemodule.cpp b/src/providers/virtual/qgsvirtuallayersqlitemodule.cpp
index 137cf9652578..4a5ac312a36a 100644
--- a/src/providers/virtual/qgsvirtuallayersqlitemodule.cpp
+++ b/src/providers/virtual/qgsvirtuallayersqlitemodule.cpp
@@ -218,7 +218,7 @@ struct VTable
             typeName = QStringLiteral( "text" );
             break;
         }
-        sqlFields << field.name() + " " + typeName;
+        sqlFields << QStringLiteral( "\"%1\" %2" ).arg( field.name(), typeName );
       }
 
       QgsVectorDataProvider *provider = mLayer ? mLayer->dataProvider() : mProvider;
diff --git a/tests/src/python/test_provider_virtual.py b/tests/src/python/test_provider_virtual.py
index 47e176efa2ab..9b4a865de256 100644
--- a/tests/src/python/test_provider_virtual.py
+++ b/tests/src/python/test_provider_virtual.py
@@ -16,6 +16,7 @@
 import os
 
 from qgis.core import (QgsVectorLayer,
+                       QgsField,
                        QgsFeature,
                        QgsFeatureRequest,
                        QgsGeometry,
@@ -847,6 +848,29 @@ def test_joined_layers_conversion(self):
 
         QgsProject.instance().removeMapLayers([v1.id(), v2.id(), v3.id()])
 
+    def testFieldsWithSpecialCharacters(self):
+        ml = QgsVectorLayer("Point?srid=EPSG:4326&field=123:int", "mem_with_nontext_fieldnames", "memory")
+        self.assertEqual(ml.isValid(), True)
+        QgsProject.instance().addMapLayer(ml)
+
+        ml.startEditing()
+        self.assertTrue(ml.addAttribute(QgsField('abc:123', QVariant.String)))
+        f1 = QgsFeature(ml.fields())
+        f1.setGeometry(QgsGeometry.fromWkt('POINT(0 0)'))
+        f2 = QgsFeature(ml.fields())
+        f2.setGeometry(QgsGeometry.fromWkt('POINT(1 1)'))
+        ml.addFeatures([f1, f2])
+        ml.commitChanges()
+
+        vl = QgsVectorLayer("?query=select * from mem_with_nontext_fieldnames", "vl", "virtual")
+        self.assertEqual(vl.isValid(), True)
+        self.assertEqual(vl.fields().at(0).name(), '123')
+        self.assertEqual(vl.fields().at(1).name(), 'abc:123')
+
+        self.assertEqual(vl.featureCount(), 2)
+
+        QgsProject.instance().removeMapLayer(ml)
+
 
 if __name__ == '__main__':
     unittest.main()