test: give the fault-guard fake backend its storage representation

download() now runs _check_storage(), which reads _ddf_shifting and the
per-level configs; the fake backend set neither. Both are set to the
unshifted default, so the download/step failure assertions run again.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

docs/validation/phase0_baseline_eec4677_20261020.txt

@@ -1,149 +0,0 @@
-CelerisLab Phase 0 baseline — original candidate SHA eec4677db1308e2a9ce4e5f195c994356c11de13
-106 isolated groups; 764 primary pytest test IDs; 741 passed, 22 failed, 1 skipped; 0 collection errors, 0 timeouts.
-Host: 595 passed / 20 failed / 1 skipped. GPU: 146 passed / 2 failed.
-Python 3.10.13; NumPy 1.26.4; pytest 9.1.1; PyCUDA 2026.1; SciPy 1.14.1; CUDA 12.4; Tesla V100-SXM2-16GB.
-CUDA_VISIBLE_DEVICES bound per GPU worker. Host mocks and real CUDA ran in separate processes; each group had a 900-second timeout.
-No source/test edits, no changed tolerance, no refreshed frozen hash, no long physics or performance runs.
-This report contains test IDs/errors only. Full logs remain on Horsea under /home/frank14f/CelerisLab-phase0-evidence-20261020/.
-11 source provenance failures bind historical experimental manifests (47b05bc8... for DFG/Jet CV; a233c903... window); they are not new physical qualification.
-The channel GPU bitwise discrepancy remains unresolved: 1/4320 values; maximum absolute difference 2.3283064e-10; relative 1.7676595e-07.
-Shifted-storage test input is FP64 because NumPy where(float32 scalar, np.nan) promotes it; library requires shifted raw FP32.
-Current scheduler uses _advance(index,...); two tests still instrument removed _advance_child.
-
-Failed IDs and original error excerpts:
-
-1. tests/unit/test_channel_root.py::test_actual_closure_read_conflicts
-Location: tests/unit/test_channel_root.py:53: in test_actual_closure_read_conflicts
-Error: E   ValueError: block_cell must be integer index(es) in [0, 960)
-Category: test_fixture_numpy_uint64_to_float64
-Log: run-004/stdout.log
-
-2. tests/unit/test_jet_circle_cv.py::Host::test_source_pin
-Location: tests/unit/test_jet_circle_cv.py:135: in test_source_pin
-Error: E   RuntimeError: Source hash mismatch: src/CelerisLab/lbm/channel.py
-Category: frozen_source_manifest_constraint
-Log: run-010/stdout.log
-
-3. tests/unit/test_re100.py::test_production_unmodified
-Location: tests/unit/test_re100.py:71: in test_production_unmodified
-Error: E   AssertionError: src/CelerisLab/lbm/channel.py | E   assert '40d0354e5dc9...f4cd75ab5a095' == '2d5b5ff43414...b58d498dd8b0f' | E      | E     - 2d5b5ff43414cb35633ac4ce90ce2c3a3353950b25c168e1c2ab58d498dd8b0f
-Category: frozen_source_manifest_constraint
-Log: run-027/stdout.log
-
-4. tests/unit/test_refined_dfg.py::test_source_pin
-Location: tests/unit/test_refined_dfg.py:20: in test_source_pin
-Error: E   RuntimeError: Source mismatch: src/CelerisLab/lbm/kernels/blocks.cu
-Category: frozen_source_manifest_constraint
-Log: run-028/stdout.log
-
-5. tests/unit/test_refined_dfg.py::test_full_requires_completed_pilot
-Location: tests/unit/test_refined_dfg.py:146: in test_full_requires_completed_pilot
-Error: E   RuntimeError: Source mismatch: src/CelerisLab/lbm/kernels/blocks.cu
-Category: frozen_source_manifest_constraint
-Log: run-028/stdout.log
-
-6. tests/unit/test_refined_dfg.py::test_pilot_validation_and_calibration
-Location: tests/unit/test_refined_dfg.py:226: in test_pilot_validation_and_calibration
-Error: E   RuntimeError: Source mismatch: src/CelerisLab/lbm/kernels/blocks.cu
-Category: frozen_source_manifest_constraint
-Log: run-028/stdout.log
-
-7. tests/unit/test_refined_dfg.py::test_reject_malformed_pilot_receipts
-Location: tests/unit/test_refined_dfg.py:236: in test_reject_malformed_pilot_receipts
-Error: E   RuntimeError: Source mismatch: src/CelerisLab/lbm/kernels/blocks.cu
-Category: frozen_source_manifest_constraint
-Log: run-028/stdout.log
-
-8. tests/unit/test_refined_dfg.py::test_reject_collision_receipts
-Location: tests/unit/test_refined_dfg.py:326: in test_reject_collision_receipts
-Error: E   RuntimeError: Source mismatch: src/CelerisLab/lbm/kernels/blocks.cu
-Category: frozen_source_manifest_constraint
-Log: run-028/stdout.log
-
-9. tests/unit/test_refined_dfg.py::test_record_actual_checkout_separately
-Location: tests/unit/test_refined_dfg.py:344: in test_record_actual_checkout_separately
-Error: E   RuntimeError: Source mismatch: src/CelerisLab/lbm/kernels/blocks.cu
-Category: frozen_source_manifest_constraint
-Log: run-028/stdout.log
-
-10. tests/unit/test_refined_dfg.py::test_window_plan_preserves_physics
-Location: tests/unit/test_refined_dfg.py:354: in test_window_plan_preserves_physics
-Error: E   RuntimeError: Source mismatch: src/CelerisLab/lbm/kernels/blocks.cu
-Category: frozen_source_manifest_constraint
-Log: run-028/stdout.log
-
-11. tests/unit/test_refined_dfg.py::test_reject_observation_mode_receipts
-Location: tests/unit/test_refined_dfg.py:365: in test_reject_observation_mode_receipts
-Error: E   RuntimeError: Source mismatch: src/CelerisLab/lbm/kernels/blocks.cu
-Category: frozen_source_manifest_constraint
-Log: run-028/stdout.log
-
-12. tests/unit/test_shifted_storage.py::ShiftedStorage::test_shifted_density_and_tag_validation
-Location: tests/unit/test_shifted_storage.py:82: in test_shifted_density_and_tag_validation
-Error: E   ValueError: shifted stored populations must be FP32
-Category: test_fixture_numpy_where_dtype
-Log: run-037/stdout.log
-
-13. tests/unit/test_validation_source_provenance.py::test_manifests_cover_current_source_and_preserve_origin
-Location: tests/unit/test_validation_source_provenance.py:40: in test_manifests_cover_current_source_and_preserve_origin
-Error: E   AssertionError: src/CelerisLab/lbm/channel.py | E   assert '40d0354e5dc9...f4cd75ab5a095' == '2d5b5ff43414...b58d498dd8b0f' | E      | E     - 2d5b5ff43414cb35633ac4ce90ce2c3a3353950b25c168e1c2ab58d498dd8b0f
-Category: frozen_source_manifest_constraint
-Log: run-049/stdout.log
-
-14. tests/validation/multigrid/test_block_stepper.py::CpuContracts::test_initialize_rejects_bad_state_before_upload
-Location: tests/validation/multigrid/test_block_stepper.py:212: in test_initialize_rejects_bad_state_before_upload
-Error: E   AttributeError: 'PeriodicBlockStepper' object has no attribute '_ddf_shifting'
-Category: test_fixture_or_assertion_stale_api
-Log: run-058/stdout.log
-
-15. tests/validation/multigrid/test_channel_root_gpu.py::ChannelRootGPU::test_uniform_matched_root
-Location: tests/validation/multigrid/test_channel_root_gpu.py:95: in test_uniform_matched_root
-Error: E   AssertionError:  | E   Arrays are not equal | E    | E   Mismatched elements: 1 / 4320 (0.0231%)
-Category: gpu_bitwise_parity_contract_failure_unresolved
-Log: run-060/stdout.log
-
-16. tests/validation/multigrid/test_fine_surface_gpu.py::test_missing_surface_device_buffer_rejects_before_launch[surface_velocity_gpu]
-Location: tests/validation/multigrid/test_fine_surface_gpu.py:284: in test_missing_surface_device_buffer_rejects_before_launch
-Error: E   AttributeError: can't set attribute 'fine_boundary'
-Category: test_fixture_or_assertion_stale_api
-Log: run-070/stdout.log
-
-17. tests/validation/multigrid/test_fine_surface_gpu.py::test_missing_surface_device_buffer_rejects_before_launch[link_exchange_gpu]
-Location: tests/validation/multigrid/test_fine_surface_gpu.py:284: in test_missing_surface_device_buffer_rejects_before_launch
-Error: E   AttributeError: can't set attribute 'fine_boundary'
-Category: test_fixture_or_assertion_stale_api
-Log: run-070/stdout.log
-
-18. tests/validation/multigrid/test_refinement_followup.py::FaultGuardsCPU::test_activation_failure_retains_resources_for_retry
-Location: tests/validation/multigrid/test_refinement_followup.py:134: in test_activation_failure_retains_resources_for_retry
-Error: E   AttributeError: can't set attribute 'fine_layout'
-Category: test_fixture_or_assertion_stale_api
-Log: run-083/stdout.log
-
-19. tests/validation/multigrid/test_refinement_followup.py::FaultGuardsCPU::test_failed_download_blocks_read_and_step
-Location: tests/validation/multigrid/test_refinement_followup.py:121: in test_failed_download_blocks_read_and_step
-Error: E   AttributeError: can't set attribute 'fine_layout'
-Category: test_fixture_or_assertion_stale_api
-Log: run-083/stdout.log
-
-20. tests/validation/multigrid/test_refinement_followup.py::FaultGuardsCPU::test_kernel_contracts_reject_before_upload
-Location: RuntimeError: level config chain is inconsistent with the pair tables
-Error: E   AssertionError: "omega/tau" does not match "level config chain is inconsistent with the pair tables"
-Category: test_fixture_or_assertion_stale_api
-Log: run-083/stdout.log
-
-21. tests/validation/multigrid/test_refinement_three_level.py::ThreeLevelCPU::test_four_halo_bfl_steps_and_fresh_middle_feeds
-Location: tests/validation/multigrid/test_refinement_three_level.py:83: in test_four_halo_bfl_steps_and_fresh_middle_feeds
-Error: E   AttributeError: 'FixedPatchStepper' object has no attribute '_advance_child'
-Category: test_instrumentation_stale_private_method
-Log: run-092/stdout.log
-
-22. tests/validation/multigrid/test_refinement_three_level.py::ThreeLevelGPU::test_nonequilibrium_masks_and_fresh_middle_feeds
-Location: tests/validation/multigrid/test_refinement_three_level.py:175: in test_nonequilibrium_masks_and_fresh_middle_feeds
-Error: E   AttributeError: 'FixedPatchStepper' object has no attribute '_advance_child'
-Category: test_instrumentation_stale_private_method
-Log: run-093/stdout.log
-
-SKIP: tests/unit/test_union_refinement.py::AdapterNumerics::test_eight_steps_bitwise
-Reason: ADAPTER_DIR external CPU adapter not configured.
-

tests/unit/test_channel_root.py

@@ -50,7 +50,7 @@ def test_masks_and_minimal_footprint():
 def test_actual_closure_read_conflicts():
     pair, layout, targets = transfer((6, 6, 18, 14))
     validate_channel_transfers(pair, layout, targets)
-    for target in (layout.slot(layout.owner[5, -1]-1, 2),
+    for target in (layout.slot(int(layout.owner[5, -1]) - 1, 2),
                    layout.slot(layout.owner[1, 4], 4),
                    layout.slot(layout.owner[-2, 4], 3)):
         with pytest.raises(ValueError, match="immutable"):

tests/unit/test_shifted_storage.py

@@ -78,13 +78,15 @@ class ShiftedStorage(unittest.TestCase):
 
     def test_shifted_density_and_tag_validation(self):
         old,new = topology(A),topology(B)
-        a = tuple(np.where(m[None], np.float32(-.001), np.nan).repeat(9,axis=0) for m in old.leaf_masks)
+        a = tuple(np.where(m[None], np.float32(-.001), np.float32(np.nan)).repeat(9,axis=0)
+                  for m in old.leaf_masks)  # FP32 under numpy 1 and 2 promotion rules
         remap(old,new,a)
         with self.assertRaisesRegex(ValueError,'representation'): remap(old,new,a,False)
         with self.assertRaisesRegex(ValueError,'FP32'): remap(old,new,tuple(x.astype(np.float64) for x in a))
         a[0][:,old.leaf_masks[0]] = -1
         with self.assertRaisesRegex(ValueError,'positive density'): remap(old,new,a)
-        rest = tuple(np.where(m[None],np.float32(0),np.nan).repeat(9,axis=0) for m in old.leaf_masks)
+        rest = tuple(np.where(m[None],np.float32(0),np.float32(np.nan)).repeat(9,axis=0)
+                     for m in old.leaf_masks)
         remap(old,new,rest)
         with self.assertRaisesRegex(ValueError,'positive density'):
             remap_synchronized(old,new,rest,base_count=7,level_steps=(7,14,28),phase='postcollision_g')

tests/validation/multigrid/test_block_stepper.py

@@ -192,6 +192,7 @@ class CpuContracts(unittest.TestCase):
         backend._lock = RLock()
         backend._status = "ready"
         backend._step_count = 0
+        backend._ddf_shifting = False  # unshifted storage, as for the default config
         backend._stream = Mock()
         backend._module = Mock()
         backend._copy = backend._step = Mock()

tests/validation/multigrid/test_fine_surface_gpu.py

@@ -281,7 +281,8 @@ def test_fine_surface_four_hops(speed):
 @pytest.mark.parametrize("missing", ["surface_velocity_gpu", "link_exchange_gpu"])
 def test_missing_surface_device_buffer_rejects_before_launch(missing):
     backend = implementation.FixedPatchStepper.__new__(implementation.FixedPatchStepper)
-    backend.fine_boundary = SimpleNamespace(objects=[object_spec(.002)])
+    backend._boundary_hosts = [None, SimpleNamespace(objects=[object_spec(.002)])]
+    backend._level_jets = [(), ()]
     backend._fine_curved = SimpleNamespace(fluid_idx_gpu=object(),
                                           surface_velocity_gpu=object(), link_exchange_gpu=object())
     setattr(backend._fine_curved, missing, None)

tests/validation/multigrid/test_refinement_followup.py

@@ -106,7 +106,9 @@ class FaultGuardsCPU(unittest.TestCase):
 
     def fake_backend(self):
         backend = PeriodicPatchStepper.__new__(PeriodicPatchStepper)
-        backend.fine_layout = None  # dense fine storage
+        backend._layouts = [None, None]  # dense storage on both levels
+        backend._ddf_shifting = False  # unshifted on every level, as _check_storage expects
+        backend._level_cfgs = [LBMConfig(nx=16, ny=16, viscosity=.1)] * 2  # ddf_shifting off
         backend.ctx = Mock(activate=nullcontext)
         backend._lock = RLock()
         backend._status = "ready"
@@ -158,7 +160,9 @@ class FaultGuardsCPU(unittest.TestCase):
         p = implementation.FixedPatch2D.from_config(cfg, (4, 4, 12, 12))
         with patch.object(cuda, "Stream"), patch.object(implementation.FixedPatch2D, "from_config",
                                                        return_value=replace(p, tau_coarse=.9)):
-            with self.assertRaisesRegex(RuntimeError, "omega/tau"):
+            # The hierarchy rejects a pair tau that disagrees with its level config
+            # (hierarchy.py) before the per-level omega/tau check can be reached.
+            with self.assertRaisesRegex(RuntimeError, "config chain is inconsistent"):
                 PeriodicPatchStepper(cfg, p.bounds, context=context)
         module = Mock()
         module.get_global.return_value = (Mock(), 16)