gis: Improved LayerMapping error message when model field doesn't mat…

…ch feature geom type.

Tweaked Field.__str__. 
Fixed geom_name aliasing bug.

git-svn-id: http://code.djangoproject.com/svn/django/branches/gis@5586 bcc190cf-cafb-0310-a4f2-bffc1f526a37

django/contrib/gis/gdal/Field.py

@@ -25,7 +25,7 @@ def __init__(self, fld, val=''):
 
     def __str__(self):
         "Returns the string representation of the Field."
-        return '%s (%s)' % (self.name, self.__class__.__name__)
+        return '%s (%s)' % (self.name, self.value)
 
     #### Field Properties ####
     @property

django/contrib/gis/utils/LayerMapping.py

@@ -158,15 +158,15 @@ def check_feature(feat, model_fields, mapping):
             geom  = feat.geom
             gtype = geom.geom_type
             gname = geom.geom_name
-            
+
             if make_multi(gname, model_type):
                 # Do we have to 'upsample' into a Geometry Collection?
                 pass
             elif gtype == ogc_types[gis_fields[model_type]]:
                 # The geometry type otherwise was expected
                 pass
             else:
-                raise Exception, 'Invalid mapping geometry!'
+                raise Exception, 'Invalid mapping geometry; model has %s, feature has %s' % (model_type, gtype)
 
         ## Handling other fields 
         else:
@@ -237,10 +237,10 @@ def save(self, verbose=False):
                 if ogr_field in ogc_types:
                     ## Getting the OGR geometry from the field
                     geom = feat.geom
-                    
+
                     if make_multi(geom.geom_name, model_type):
                         # Constructing a multi-geometry type to contain the single geometry
-                        multi_type = multi_types[gname]
+                        multi_type = multi_types[geom.geom_name]
                         g = OGRGeometry(multi_type)
                         g.add(geom)
                     else: