refactor: remove redundant periodic patch stepper alias

tests/validation/multigrid/test_refinement_followup.py

@@ -20,7 +20,7 @@ from CelerisLab.lbm import refinement_stepper as implementation
 from CelerisLab.lbm.blocks import BlockLayout2D
 from test_refinement_gpu import (ROOT, POP_ATOL, MOMENT_ATOL, ref, postcollision,
                                  totals, LBMConfig, CudaContext, compiler,
-                                 PeriodicPatchStepper)
+                                 FixedPatchStepper)
 
 
 def scalar_interval(coarse, fine, bounds, slot=None):
@@ -123,7 +123,7 @@ class FaultGuardsCPU(unittest.TestCase):
                                                      refinements=[bounds], level_blocks=[(1, 1)] * 2)
 
     def fake_backend(self):
-        backend = PeriodicPatchStepper.__new__(PeriodicPatchStepper)
+        backend = FixedPatchStepper.__new__(FixedPatchStepper)
         layout = BlockLayout2D.build(1, 1, 1, 1, periodic=(False, False))
         backend._layouts = [layout, layout]  # blocked storage on both levels
         backend._ddf_shifting = False  # unshifted on every level, as _check_storage expects
@@ -175,7 +175,7 @@ class FaultGuardsCPU(unittest.TestCase):
         context = Mock(activate=nullcontext, sm_arch="sm_70")
         with patch.object(implementation, "HALO", 2):
             with self.assertRaisesRegex(RuntimeError, "four-cell"):
-                PeriodicPatchStepper(cfg, context=context, refinements=[(4, 4, 12, 12)],
+                FixedPatchStepper(cfg, context=context, refinements=[(4, 4, 12, 12)],
                                      level_blocks=[(16, 16), (24, 24)])
         p = implementation.FixedPatch2D.from_config(cfg, (4, 4, 12, 12))
         from CelerisLab.lbm import hierarchy
@@ -187,11 +187,11 @@ class FaultGuardsCPU(unittest.TestCase):
         with patch.object(cuda, "Stream"), patch.object(cuda, "mem_get_info", return_value=(1 << 40, 1 << 40)), bad, patch.object(cuda, "mem_alloc") as alloc, \
                 patch.object(cuda, "memcpy_htod") as upload:
             with self.assertRaisesRegex(RuntimeError, "config chain is inconsistent"):
-                PeriodicPatchStepper(cfg, context=context, refinements=[p.bounds],
+                FixedPatchStepper(cfg, context=context, refinements=[p.bounds],
                                      level_blocks=[(16, 16), (24, 24)])
             with patch.object(hierarchy, "_check_chain"), \
                     self.assertRaisesRegex(RuntimeError, "omega/tau"):
-                PeriodicPatchStepper(cfg, context=context, refinements=[p.bounds],
+                FixedPatchStepper(cfg, context=context, refinements=[p.bounds],
                                      level_blocks=[(16, 16), (24, 24)])
             alloc.assert_not_called()
             upload.assert_not_called()
@@ -202,7 +202,7 @@ class FaultGuardsCPU(unittest.TestCase):
                 patch.object(compiler, "load_module", return_value=module), \
                 patch.object(cuda, "memcpy_htod") as upload:
             with self.assertRaisesRegex(RuntimeError, "layout mismatch"):
-                PeriodicPatchStepper(cfg, context=context, refinements=[p.bounds],
+                FixedPatchStepper(cfg, context=context, refinements=[p.bounds],
                                      level_blocks=[(16, 16), (24, 24)])
             upload.assert_not_called()
 
@@ -348,7 +348,7 @@ class NormalBuildGPU(unittest.TestCase):
         state = ref.State(*(a * (1 + 1e-3*rng.standard_normal(a.shape))
                             for a in (initial.coarse_f, initial.fine_f)))
         max_pop = max_drift = max_moment = 0.0
-        with CudaContext(0) as context, PeriodicPatchStepper(
+        with CudaContext(0) as context, FixedPatchStepper(
                 LBMConfig(nx=16, ny=16, viscosity=.1), context=context,
                 refinements=[(4, 4, 12, 12)], level_blocks=[(16, 16), (24, 24)]) as backend:
             backend.initialize(*postcollision(state, spec, maps))
@@ -381,7 +381,7 @@ class NormalBuildGPU(unittest.TestCase):
         fine_mask[4:-4, 4:-4] = True
         initial[1][:, ~fine_mask] = np.nan
         expected = scalar_interval(*[a.astype(np.float64) for a in initial], bounds)
-        with CudaContext(0) as context, PeriodicPatchStepper(cfg, context=context, refinements=[bounds],
+        with CudaContext(0) as context, FixedPatchStepper(cfg, context=context, refinements=[bounds],
                                                              level_blocks=[(13, 17), (14, 16)]) as backend:
             self.assertEqual(backend.patch.fine_shape, (14, 16))
             p = backend.patch