Geometry conversion test

geom_tests.py

from ebpub.utils.geodjango import ensure_valid
from ebpub.utils.geodjango import flatten_geomcollection

def convert1(geom, srid=4326):
    # Karen's version
    geom = geom.transform(srid, True)
    if hasattr(geom, 'geos'):
        geom = geom.geos
    return geom


def convert2(geom, srid=4326):
    # Paul's version
    if hasattr(geom, 'geos'):
        geom = geom.geos
    geom = geom.clone()
    if geom.srid is None:
        geom.srid = srid
    elif geom.srid != srid:
        geom = geom.transform(srid, True)
    geom = ensure_valid(geom)
    geom = flatten_geomcollection(geom)
    return geom

from django.contrib.gis.geos import Point
from django.contrib.gis.gdal import OGRGeometry

geosp_no_srid = Point((1.0, 2.0))
ogrp_no_srid = OGRGeometry(geosp_no_srid.wkt)

geosp_with_srid = Point((1.0, 2.0), srid=4326)
ogrp_with_srid = OGRGeometry(geosp_with_srid.wkt, srs=4326)

assert geosp_with_srid.srid == 4326
assert geosp_no_srid.srid == None
assert ogrp_with_srid.srid == 4326
assert ogrp_no_srid.srid == None

assert ogrp_with_srid.geos == geosp_with_srid
assert ogrp_no_srid.geos == geosp_no_srid
assert ogrp_with_srid.geos.srid == 4326
assert ogrp_no_srid.geos.srid == None

# assert convert(geosp_with_srid).srid == 4326
# assert convert(geosp_no_srid).srid == 4326
# assert convert(ogrp_with_srid).srid == 4326
# assert convert(ogrp_no_srid).srid == 4326

for name in ('geosp_with_srid', 'geosp_no_srid',
             'ogrp_with_srid', 'ogrp_no_srid'):
    geom = eval(name)
    for func in (convert1, convert2):
        print "\n\n==== %s on %s ====\n" % (func.__name__, name)
        print "orig SRID: %s, WKT: %s" % (geom.srid, geom.wkt)

        try:
            result = func(geom)
        except Exception as e:
            print "Got exception from %s: %s" % (func.__name__, e)
            continue
        if result is None:
            print "%s returned None!" % func.__name__
            continue

        print "new SRID:  %s, WKT: %s" % (result.srid, result.wkt)

print