test: completed tests for geometry

packages/geometry/lib/src/geometry.dart

@@ -37,8 +37,6 @@ List<Vector2> calculateArc({
 ///
 /// An ellipse can be achieved by specifying a [center], a [bigRadius] and a
 /// [smallRadius].
-/// In addition, a semi-ellipse can be achieved by specifying its [angle] and an
-/// [offsetAngle] (both in radians).
 ///
 /// The higher the [precision], the more [Vector2]s will be calculated;
 /// achieving a more rounded ellipse.

packages/geometry/test/src/geometry_test.dart

@@ -52,6 +52,25 @@ void main() {
       );
       expect(points.length, 50);
     });
+
+    test('fails if radius not in range', () {
+      expect(
+        () => calculateEllipse(
+          center: Vector2.zero(),
+          bigRadius: 100,
+          smallRadius: 150,
+        ),
+        throwsA(isA<AssertionError>()),
+      );
+      expect(
+        () => calculateEllipse(
+          center: Vector2.zero(),
+          bigRadius: 100,
+          smallRadius: 0,
+        ),
+        throwsA(isA<AssertionError>()),
+      );
+    });
   });
 
   group('calculateBezierCurve', () {