replace empty returns in tests with annotated pytest.skip() calls. closes #1076 (#1356)

Author: slayoo

tests/smoke_tests/box/berry_1967/test_coalescence.py

@@ -22,10 +22,10 @@
 @pytest.mark.parametrize("adaptive", (True, False))
 @pytest.mark.parametrize("kernel", (Geometric(), Electric(), Hydrodynamic()))
 def test_coalescence(backend_class, kernel, croupier, adaptive):
-    if backend_class == ThrustRTC and croupier == "local":  # TODO #358
-        return
-    if backend_class == ThrustRTC and adaptive and croupier == "global":  # TODO #329
-        return
+    if backend_class == ThrustRTC and croupier == "local":
+        pytest.skip("TODO #358")
+    if backend_class == ThrustRTC and adaptive and croupier == "global":
+        pytest.skip("TODO #329")
     # Arrange
     s = Settings()
     s.formulae.seed = 0

tests/unit_tests/dynamics/collisions/test_croupiers.py

@@ -12,7 +12,7 @@
 @pytest.mark.parametrize("croupier", ["local", "global"])
 def test_final_state(croupier, backend_class):
     if backend_class is ThrustRTC:
-        return  # TODO #330
+        pytest.skip("TODO #330")
 
     # Arrange
     n_part = 100000

tests/unit_tests/dynamics/collisions/test_sdm_multi_cell.py

@@ -16,9 +16,8 @@ class TestSDMMultiCell:  # pylint: disable=too-few-public-methods
     @pytest.mark.parametrize("n_sd", [2, 3, 8000])
     @pytest.mark.parametrize("adaptive", [False, True])
     def test_coalescence_call(n_sd, backend_class, adaptive):
-        # TODO #330
         if backend_class is ThrustRTC:
-            return
+            pytest.skip("TODO #330")
 
         # Arrange
         n = np.ones(n_sd)

tests/unit_tests/impl/test_particle_attributes.py

@@ -172,8 +172,8 @@ def test_permutation_global_as_implemented_in_numba():
 
     @staticmethod
     def test_permutation_local(backend_class):
-        if backend_class is GPU:  # TODO #358
-            return
+        if backend_class is GPU:
+            pytest.skip("TODO #358")
         n_sd = 8
         u01 = [0.1, 0.4, 0.2, 0.5, 0.9, 0.1, 0.6, 0.3]
         cell_start = [0, 0, 2, 5, 7, n_sd]
@@ -203,7 +203,7 @@ def test_permutation_local(backend_class):
     @staticmethod
     def test_permutation_global_repeatable(backend_class):
         if backend_class is ThrustRTC:
-            return  # TODO #328
+            pytest.skip("TODO #328")
 
         n_sd = 800
         u01 = np.random.random(n_sd)
@@ -233,8 +233,8 @@ def test_permutation_global_repeatable(backend_class):
 
     @staticmethod
     def test_permutation_local_repeatable(backend_class):
-        if backend_class is GPU:  # TODO #358
-            return
+        if backend_class is GPU:
+            pytest.skip("TODO #358")
         n_sd = 800
         idx = range(n_sd)
         u01 = np.random.random(n_sd)