Clarify raw exchange metadata and streamline host tests

src/CelerisLab/lbm/refinement_stepper.py

@@ -21,7 +21,8 @@ from .block_stepper import MAX_GRID_DIM
 from .hierarchy import build_hierarchy, is_rectangle
 from .refinement import ACTIVE, HALO, FixedPatch2D, FixedPatchSet2D, prepare_fine_boundary
 from .refinement_tables import (blocked_base_tables, blocked_fine_tables,  # noqa: F401 (re-export)
-                                blocked_kind, _prepare_blocked_boundary)
+                                blocked_kind, _prepare_blocked_boundary,
+                                BLOCKED_BOUNDARY_DEVICE_COLUMNS)
 from .descriptors import SOLID
 from .raw_exchange import summarize_exchange
 
@@ -335,8 +336,8 @@ class FixedPatchStepper:
                     b = level.boundary
                     if b is not None:
                         b.flags = self._upload(b.tables["flags"])
-                        columns = ("block", "cell", "dir", "q", "fallback", "surface_velocity")
-                        b.device = {k: self._upload(v) for k, v in b.tables.items() if k in columns}
+                        b.device = {k: self._upload(v) for k, v in b.tables.items()
+                                    if k in BLOCKED_BOUNDARY_DEVICE_COLUMNS}
                         if self._observe_raw_exchange:
                             b.device.update(rx=self._upload(b.tables["rx"]),
                                             ry=self._upload(b.tables["ry"]))

src/CelerisLab/lbm/refinement_tables.py

@@ -66,6 +66,11 @@ def blocked_base_tables(patch, layout, order, wall_aware=False, *, composed_kind
             blocked_kind(layout, dense_kind))
 
 
+# Required device columns plus optional actuation; observation arms are uploaded
+# separately only when enabled. body_id/aperture remain host reduction metadata.
+BLOCKED_BOUNDARY_DEVICE_COLUMNS = ("block", "cell", "dir", "q", "fallback", "surface_velocity")
+
+
 @dataclass
 class _BlockedBoundary:
     """One level's stationary BFL data and mutable Jet velocity column."""
@@ -87,10 +92,8 @@ def _prepare_blocked_boundary(boundary, layout, cfg, jets):
         return None
     fluid_idx, dirs, q, body_id, rx, ry, _, fallback = boundary.curved_host
     tables, _ = blocked_link_tables(layout, boundary.flags, fluid_idx, dirs, q, fallback)
-    # Physical row identity excludes body_id: duplicate owners are always wrong.
-    keys = np.column_stack((fluid_idx, dirs))
-    if len(np.unique(keys, axis=0)) != len(keys):
-        raise ValueError("duplicate physical boundary cut-link")
+    # blocked_link_tables/map_cut_links already rejects repeated (fluid_idx, dir),
+    # independently of body_id, and repeated local writers.
     tables.update(body_id=np.asarray(body_id, np.int32), rx=np.asarray(rx, np.float32),
                   ry=np.asarray(ry, np.float32), aperture=np.zeros(len(dirs), bool))
     actuated = bool(jets) or any(o.surface_actuation is not None for o in boundary.objects)