From a449b7ef99efdbb5edc8b4aacc89eb6020145dd3 Mon Sep 17 00:00:00 2001
From: Sergey Fedoseev <fedoseev.sergey@gmail.com>
Date: Fri, 30 Oct 2015 19:47:35 +0500
Subject: [PATCH] Fixed #25629 -- Added checks of the number of arguments for
 GeoDjango DB functions.

---
 django/contrib/gis/db/models/functions.py | 24 ++++++++++++++---------
 tests/gis_tests/geoapp/test_functions.py  |  3 +++
 2 files changed, 18 insertions(+), 9 deletions(-)

diff --git a/django/contrib/gis/db/models/functions.py b/django/contrib/gis/db/models/functions.py
index 55324a8eaa..c222f08b1b 100644
--- a/django/contrib/gis/db/models/functions.py
+++ b/django/contrib/gis/db/models/functions.py
@@ -125,6 +125,8 @@ class OracleToleranceMixin(object):
 
 
 class Area(OracleToleranceMixin, GeoFunc):
+    arity = 1
+
     def as_sql(self, compiler, connection):
         if connection.ops.geography:
             # Geography fields support area calculation, returns square meters.
@@ -204,11 +206,11 @@ class BoundingCircle(GeoFunc):
 
 
 class Centroid(OracleToleranceMixin, GeoFunc):
-    pass
+    arity = 1
 
 
 class Difference(OracleToleranceMixin, GeoFuncWithGeoParam):
-    pass
+    arity = 2
 
 
 class DistanceResultMixin(object):
@@ -267,11 +269,11 @@ class Distance(DistanceResultMixin, OracleToleranceMixin, GeoFuncWithGeoParam):
 
 
 class Envelope(GeoFunc):
-    pass
+    arity = 1
 
 
 class ForceRHR(GeoFunc):
-    pass
+    arity = 1
 
 
 class GeoHash(GeoFunc):
@@ -285,7 +287,7 @@ class GeoHash(GeoFunc):
 
 
 class Intersection(OracleToleranceMixin, GeoFuncWithGeoParam):
-    pass
+    arity = 2
 
 
 class Length(DistanceResultMixin, OracleToleranceMixin, GeoFunc):
@@ -329,14 +331,17 @@ class Length(DistanceResultMixin, OracleToleranceMixin, GeoFunc):
 
 class MemSize(GeoFunc):
     output_field_class = IntegerField
+    arity = 1
 
 
 class NumGeometries(GeoFunc):
     output_field_class = IntegerField
+    arity = 1
 
 
 class NumPoints(GeoFunc):
     output_field_class = IntegerField
+    arity = 1
 
     def as_sqlite(self, compiler, connection):
         if self.source_expressions[self.geom_param_pos].output_field.geom_type != 'LINESTRING':
@@ -346,6 +351,7 @@ class NumPoints(GeoFunc):
 
 class Perimeter(DistanceResultMixin, OracleToleranceMixin, GeoFunc):
     output_field_class = FloatField
+    arity = 1
 
     def as_postgresql(self, compiler, connection):
         dim = min(f.dim for f in self.get_source_fields())
@@ -355,11 +361,11 @@ class Perimeter(DistanceResultMixin, OracleToleranceMixin, GeoFunc):
 
 
 class PointOnSurface(OracleToleranceMixin, GeoFunc):
-    pass
+    arity = 1
 
 
 class Reverse(GeoFunc):
-    pass
+    arity = 1
 
 
 class Scale(SQLiteDecimalToFloatMixin, GeoFunc):
@@ -396,7 +402,7 @@ class SnapToGrid(SQLiteDecimalToFloatMixin, GeoFunc):
 
 
 class SymDifference(OracleToleranceMixin, GeoFuncWithGeoParam):
-    pass
+    arity = 2
 
 
 class Transform(GeoFunc):
@@ -432,4 +438,4 @@ class Translate(Scale):
 
 
 class Union(OracleToleranceMixin, GeoFuncWithGeoParam):
-    pass
+    arity = 2
diff --git a/tests/gis_tests/geoapp/test_functions.py b/tests/gis_tests/geoapp/test_functions.py
index ff99cc4855..d778810480 100644
--- a/tests/gis_tests/geoapp/test_functions.py
+++ b/tests/gis_tests/geoapp/test_functions.py
@@ -160,6 +160,9 @@ class GISFunctionsTests(TestCase):
         for state in qs:
             self.assertTrue(state.poly.centroid.equals_exact(state.centroid, tol))
 
+        with self.assertRaisesMessage(TypeError, "'Centroid' takes exactly 1 argument (2 given)"):
+            State.objects.annotate(centroid=functions.Centroid('poly', 'poly'))
+
     @skipUnlessDBFeature("has_Difference_function")
     def test_difference(self):
         geom = Point(5, 23, srid=4326)