Merge pull request #1696 from greglucas/v0.18.x

V0.18.x

lib/cartopy/mpl/geoaxes.py

@@ -306,7 +306,12 @@ def wrapper(self, *args, **kwargs):
         transform = kwargs.get('transform', None)
         if transform is None:
             transform = self.projection
-        if (isinstance(transform, ccrs.CRS) and
+        # Raise an error if any of these functions try to use
+        # a spherical source CRS.
+        non_spherical_funcs = ['contour', 'contourf', 'pcolormesh', 'pcolor',
+                               'quiver', 'barbs', 'streamplot']
+        if (func.__name__ in non_spherical_funcs and
+                isinstance(transform, ccrs.CRS) and
                 not isinstance(transform, ccrs.Projection)):
             raise ValueError('Invalid transform: Spherical {} '
                              'is not supported - consider using '
@@ -501,11 +506,12 @@ def draw(self, renderer=None, **kwargs):
         #       caching the resulting image;
         #       buffering the result by 10%...;
         if not self._done_img_factory:
-            for factory, args, kwargs in self.img_factories:
+            for factory, factory_args, factory_kwargs in self.img_factories:
                 img, extent, origin = factory.image_for_domain(
-                    self._get_extent_geom(factory.crs), args[0])
+                    self._get_extent_geom(factory.crs), factory_args[0])
                 self.imshow(img, extent=extent, origin=origin,
-                            transform=factory.crs, *args[1:], **kwargs)
+                            transform=factory.crs, *factory_args[1:],
+                            **factory_kwargs)
         self._done_img_factory = True
 
         return matplotlib.axes.Axes.draw(self, renderer=renderer, **kwargs)