#13788: GEOSGeometry.transform() silently no-ops when GDAL isn't available or srid is None ---------------------------------+------------------------------------------ Reporter: rcoup | Owner: nobody Status: new | Milestone: 1.3 Component: GIS | Version: SVN Keywords: transform geos gdal | Stage: Unreviewed Has_patch: 0 | ---------------------------------+------------------------------------------ `GEOSGeometry.transform()` uses the GDAL library to re-project geometries. If GDAL is not available however, it silently does nothing.
Geodjango-Users discussion thread: http://groups.google.com/group/geodjango/browse_thread/thread/788cafdbd592d617 Current behaviour if GDAL is unavailable: * `.transform(clone=False)` (the default) does nothing * `.transform(clone=True)` returns `None` Also related: * `.transform(clone=False)` (the default) called on a geometry where `.srid` is `None` does nothing * `.transform(clone=True)` called on a geometry where `.srid` is `None` returns `None` Since `transform(clone=False)` (the default) mutates the geometry, it should raise an exception if it can't do what the caller asked. The attached patch: * short-circuits re-projection if the source and destination SRIDs match * makes `.transform()` raise a GEOSGeometry.Error if GDAL isn't available * adds tests around the new behaviour * adds a `FutureWarning` if the srid of the geometry is `None` or <0, pointing out that in 1.5 the behaviour will change an error will be raised. * adds some docs, including notes to the backwards-incompatibilities for 1.3 The backwards incompatible behaviour change is being introduced because: * `.transform()` no-op'ing if source & destination SRIDs don't match is NOT what the caller wants - it is in all cases a bug. * It's unlikely the user was manually checking either the return value (`clone=True`) or the geometry's srid (`clone=False`) and raising their own exception, the more common case would be to assert on `HAS_GDAL`. -- Ticket URL: <http://code.djangoproject.com/ticket/13788> Django <http://code.djangoproject.com/> The Web framework for perfectionists with deadlines. -- You received this message because you are subscribed to the Google Groups "Django updates" group. To post to this group, send email to django-upda...@googlegroups.com. To unsubscribe from this group, send email to django-updates+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/django-updates?hl=en.
