fixed Sphere._vertices used before populated

Author: chenkasirer

CHANGELOG.md

@@ -11,6 +11,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Changed
 
+* Fixed `NoneType` error when calling `compas.geometry.Sphere.edges`.
+
 ### Removed
 
 

src/compas/geometry/shapes/sphere.py

@@ -218,7 +218,7 @@ def compute_faces(self):  # type: () -> list[list[int]]
         u = self.resolution_u
         v = self.resolution_v
 
-        vertices = self._vertices
+        vertices = self.vertices
 
         faces = []
 

tests/compas/geometry/test_shpere.py

@@ -0,0 +1,15 @@
+import pytest
+
+from compas.geometry import Frame
+from compas.geometry import Sphere
+
+
+@pytest.fixture
+def sphere():
+    return Sphere(450.0, Frame.worldXY())
+
+
+def test_sphere_discretization(sphere):
+    assert len(sphere.edges) == 496
+    assert len(sphere.faces) == 256
+    assert len(sphere.vertices) == 242