From 7d42a4b0e925745efd7036482ab7b8c58991d71a Mon Sep 17 00:00:00 2001
From: Sandro Santilli <strk@kbt.io>
Date: Tue, 11 Oct 2016 12:54:12 +0200
Subject: [PATCH] Add test for #15188 (this branch is unaffected by the bug)

---
 tests/src/python/test_provider_postgres.py | 43 +++++++++++++++++++++-
 1 file changed, 42 insertions(+), 1 deletion(-)

diff --git a/tests/src/python/test_provider_postgres.py b/tests/src/python/test_provider_postgres.py
index 6c549cee9924..8b3d1ab45706 100644
--- a/tests/src/python/test_provider_postgres.py
+++ b/tests/src/python/test_provider_postgres.py
@@ -13,10 +13,19 @@
 __revision__ = '$Format:%H$'
 
 import qgis
+import psycopg2
+
 import os
 from qgis.core import NULL
 
-from qgis.core import QgsVectorLayer, QgsFeatureRequest, QgsFeature, QgsProviderRegistry
+from qgis.core import (
+    QgsVectorLayer,
+    QgsFeatureRequest,
+    QgsVectorLayerImport,
+    QgsFeature,
+    QgsProviderRegistry,
+    NULL
+)
 from PyQt4.QtCore import QSettings, QDate, QTime, QDateTime, QVariant
 from qgis.testing import (start_app,
                           unittest
@@ -43,11 +52,20 @@ def setUpClass(cls):
         cls.poly_vl = QgsVectorLayer(cls.dbconn + ' sslmode=disable key=\'pk\' srid=4326 type=POLYGON table="qgis_test"."some_poly_data" (geom) sql=', 'test', 'postgres')
         assert(cls.poly_vl.isValid())
         cls.poly_provider = cls.poly_vl.dataProvider()
+        cls.con = psycopg2.connect(cls.dbconn)
 
     @classmethod
     def tearDownClass(cls):
         """Run after all tests"""
 
+    def execSQLCommand(self, sql):
+        self.assertTrue(self.con)
+        cur = self.con.cursor()
+        self.assertTrue(cur)
+        cur.execute(sql)
+        cur.close()
+        self.con.commit()
+
     def enableCompiler(self):
         QSettings().setValue(u'/qgis/compileExpressions', True)
 
@@ -166,6 +184,29 @@ def test_query_attribute(dbconn, query, att, val, fidval):
         test_query_attribute(self.dbconn, '(SELECT -1::int8 i, NULL::geometry(Point) g)', 'i', -1, 1)
         test_query_attribute(self.dbconn, '(SELECT -65535::int8 i, NULL::geometry(Point) g)', 'i', -65535, 1)
 
+    # See http://hub.qgis.org/issues/18155
+    def testNumericPrecision(self):
+        uri = 'point?field=f1:int'
+        uri += '&field=f2:double(6,4)'
+        uri += '&field=f3:string(20)'
+        lyr = QgsVectorLayer(uri, "x", "memory")
+        self.assertTrue(lyr.isValid())
+        f = QgsFeature(lyr.fields())
+        f['f1'] = 1
+        f['f2'] = 123.456
+        f['f3'] = '12345678.90123456789'
+        lyr.dataProvider().addFeatures([f])
+        uri = '%s table="qgis_test"."b18155" (g) key=\'f1\'' % (self.dbconn)
+        self.execSQLCommand('DROP TABLE IF EXISTS qgis_test.b18155')
+        err = QgsVectorLayerImport.importLayer(lyr, uri, "postgres", lyr.crs())
+        self.assertEqual(err[0], QgsVectorLayerImport.NoError,
+                         'unexpected import error {0}'.format(err))
+        lyr = QgsVectorLayer(uri, "y", "postgres")
+        self.assertTrue(lyr.isValid())
+        f = next(lyr.getFeatures())
+        self.assertEqual(f['f1'], 1)
+        self.assertEqual(f['f2'], 123.456)
+        self.assertEqual(f['f3'], '12345678.90123456789')
 
 if __name__ == '__main__':
     unittest.main()