"""Persistence tests"""
import pickle
import struct
import unittest
from shapely import wkb, wkt
from shapely.geometry import Point
class PersistTestCase(unittest.TestCase):
def test_pickle(self):
p = Point(0.0, 0.0)
data = pickle.dumps(p)
q = pickle.loads(data)
assert q.equals(p)
def test_wkb(self):
p = Point(0.0, 0.0)
wkb_big_endian = wkb.dumps(p, big_endian=True)
wkb_little_endian = wkb.dumps(p, big_endian=False)
# Regardless of byte order, loads ought to correctly recover the
# geometry
assert p.equals(wkb.loads(wkb_big_endian))
assert p.equals(wkb.loads(wkb_little_endian))
def test_wkb_dumps_endianness(self):
p = Point(0.5, 2.0)
wkb_big_endian = wkb.dumps(p, big_endian=True)
wkb_little_endian = wkb.dumps(p, big_endian=False)
assert wkb_big_endian != wkb_little_endian
# According to WKB specification in section 3.3 of OpenGIS
# Simple Features Specification for SQL, revision 1.1, the
# first byte of a WKB representation indicates byte order.
# Big-endian is 0, little-endian is 1.
assert wkb_big_endian[0] == 0
assert wkb_little_endian[0] == 1
# Check that the doubles (0.5, 2.0) are in correct byte order
double_size = struct.calcsize("d")
assert wkb_big_endian[(-2 * double_size) :] == struct.pack(">2d", p.x, p.y)
assert wkb_little_endian[(-2 * double_size) :] == struct.pack("<2d", p.x, p.y)
def test_wkt(self):
p = Point(0.0, 0.0)
text = wkt.dumps(p)
assert text.startswith("POINT")
pt = wkt.loads(text)
assert pt.equals(p)