Invalid error reporting when importing MapInfo layer with Unknown type

[Evgeny Sizikov]

When going to import a spatial data from an MapInfo file I've stacked with an error message like following:

...
  File "../django/contrib/gis/utils/layermapping.py", line 293, in check_layer
    raise LayerMapError('Invalid mapping geometry; model has %s, feature has %s.' % (fld_name, ltype))
django.contrib.gis.utils.layermapping.LayerMapError: Invalid mapping geometry; model has PolygonField, feature has Polygon.

It took about 2 hours to figure out what could be wrong here, as the error message looks like a nonsense (Polygon != Polygon)

Looking through the code I've found a possible reason of such a misunderstanding:

layermapping.py

@@ -290 +290 @@
                 # Making sure that the OGR Layer's Geometry is compatible.
                 ltype = self.layer.geom_type
                 if not (gtype == ltype or self.make_multi(ltype, model_field)):
-                    raise LayerMapError('Invalid mapping geometry; model has %s, feature has %s.' % (fld_name, gtype))
+                    raise LayerMapError('Invalid mapping geometry; model has %s, feature has %s.' % (fld_name, ltype))
 
                 # Setting the `geom_field` attribute w/the name of the model field
                 # that is a Geometry.

After that been done I've got a meaningful error like this one:

  File "../django/contrib/gis/utils/layermapping.py", line 293, in check_layer
    raise LayerMapError('Invalid mapping geometry; model has %s, feature has %s.' % (fld_name, ltype))
django.contrib.gis.utils.layermapping.LayerMapError: Invalid mapping geometry; model has PolygonField, feature has Unknown.

It became clear to me that LayerMapping complains to import from a MapInfo layer with Unknown geometry type. That's what I was looking for 2 hours!

However, that "... model has PolygonField, feature has Unknown." doesn't looks polished too. Could someone provide a better fix?

[jbronn]

(In [12880]) Fixed #11785 -- Clarified error message when the layer geometry type doesn't match the model field. Thanks, esizikov for bug report and initial patch.