gis: Fixed #7579; no longer attempt to transform input geometries if GeometryField has its SRID set to -1.

git-svn-id: http://code.djangoproject.com/svn/django/branches/gis@7840 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/contrib/gis/db/models/fields/__init__.py

@@ -120,13 +120,15 @@ class GeometryField(SpatialBackend.Field):
 
     def get_srid(self, geom):
         """
-        Has logic for retrieving the default SRID taking into account 
-        the SRID of the field.
+        Returns the default SRID for the given geometry, taking into account
+        the SRID set for the field.  For example, if the input geometry
+        has no SRID, then that of the field will be returned.
         """
-        if geom.srid is None or (geom.srid == -1 and self._srid != -1):
+        gsrid = geom.srid # SRID of given geometry.
+        if gsrid is None or self._srid == -1 or (gsrid == -1 and self._srid != -1):
             return self._srid
         else:
-            return geom.srid
+            return gsrid
 
     ### Routines overloaded from Field ###
     def contribute_to_class(self, cls, name):
@@ -171,12 +173,10 @@ class GeometryField(SpatialBackend.Field):
 
     def get_db_prep_save(self, value):
         "Prepares the value for saving in the database."
-        if isinstance(value, SpatialBackend.Geometry):
-            return SpatialBackend.Adaptor(value)
-        elif value is None:
+        if value is None:
             return None
         else:
-            raise TypeError('Geometry Proxy should only return Geometry objects or None.')
+            return SpatialBackend.Adaptor(self.get_geometry(value))
 
     def get_manipulator_field_objs(self):
         "Using the WKTField (oldforms) to be our manipulator."

django/contrib/gis/tests/geoapp/models.py

@@ -27,3 +27,7 @@ class Feature(models.Model):
     geom = models.GeometryField()
     objects = models.GeoManager()
     def __unicode__(self): return self.name
+
+class MinusOneSRID(models.Model):
+    geom = models.PointField(srid=-1) # Minus one SRID.
+    objects = models.GeoManager()

django/contrib/gis/tests/geoapp/tests.py

@@ -1,5 +1,5 @@
 import os, unittest
-from models import Country, City, State, Feature
+from models import Country, City, State, Feature, MinusOneSRID
 from django.contrib.gis import gdal
 from django.contrib.gis.db.backend import SpatialBackend
 from django.contrib.gis.geos import *
@@ -302,6 +302,12 @@ class GeoModelTest(unittest.TestCase):
         self.assertAlmostEqual(wgs_pnt.x, sa.point.x, 6)
         self.assertAlmostEqual(wgs_pnt.y, sa.point.y, 6)
 
+        # If the GeometryField SRID is -1, then we shouldn't perform any
+        # transformation if the SRID of the input geometry is different.
+        m1 = MinusOneSRID(geom=Point(17, 23, srid=4326))
+        m1.save()
+        self.assertEqual(-1, m1.geom.srid)
+
     # Oracle does not support NULL geometries in its spatial index for
     # some routines (e.g., SDO_GEOM.RELATE).
     @no_oracle