Ticket #17736: 17736_gis_precision.diff

django/contrib/gis/geos/tests/test_geos.py

@@ -381 +381 @@
         p = Polygon.from_bbox( bbox )
         self.assertEqual(bbox, p.extent)
 
+        # Testing numerical precision when using `from_bbox`
+        x = 3.14159265358979323
+        B = (0, 0, 1, x)
+        p = Polygon.from_bbox(B)
+        y = p.extent[-1]
+        self.assertEqual(format(x, '.13f'), format(y, '.13f'))
+
         prev = fromstr('POINT(0 0)')
         for p in self.geometries.polygons:
             # Creating the Polygon, testing its properties.

django/contrib/gis/geos/polygon.py

@@ -55 +55 @@
     def from_bbox(cls, bbox):
         "Constructs a Polygon from a bounding box (4-tuple)."
         x0, y0, x1, y1 = bbox
-        return GEOSGeometry( 'POLYGON((%s %s, %s %s, %s %s, %s %s, %s %s))' %  (
-                x0, y0, x0, y1, x1, y1, x1, y0, x0, y0) )
+        for z in bbox:
+            if not isinstance(z, (int, long, float)):
+                return GEOSGeometry('POLYGON((%s %s, %s %s, %s %s, %s %s, %s %s))' %
+                                    (x0, y0, x0, y1, x1, y1, x1, y0, x0, y0))
+        return Polygon(((x0, y0), (x0, y1), (x1, y1), (x1, y0), (x0, y0)))
 
     ### These routines are needed for list-like operation w/ListMixin ###
     def _create_polygon(self, length, items):