Test that scale_activation changes AffineCouplingTransform results

Author: dennisprangle

tests/transforms/coupling_test.py

@@ -71,6 +71,18 @@ def test_forward_inverse_are_consistent(self):
             with self.subTest(shape=shape):
                 self.assert_forward_inverse_are_consistent(transform, inputs)
 
+    def test_scale_activation_has_an_effect(self):
+        for shape in self.shapes:
+            inputs = torch.randn(batch_size, *shape)
+            transform, mask = create_coupling_transform(
+                coupling.AffineCouplingTransform, shape
+            )
+            outputs_default, logabsdet_default = transform(inputs)
+            transform.scale_activation = coupling.AffineCouplingTransform.GENERAL_SCALE_ACTIVATION
+            outputs_general, logabsdet_general = transform(inputs)
+            with self.subTest(shape=shape):
+                self.assertNotEqual(outputs_default, outputs_general)
+                self.assertNotEqual(logabsdet_default, logabsdet_general)
 
 class AdditiveTransformTest(TransformTest):
     shapes = [[20], [2, 4, 4]]