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Author: zhx06

isaaclab_arena/relations/relations.py

@@ -125,6 +125,11 @@ class NoCollision(Relation):
     unordered pair once.
 
     Note: Loss computation is handled by NoCollisionLossStrategy in relation_loss_strategies.py.
+
+    NOTE: If both A.add_relation(NoCollision(B)) and B.add_relation(NoCollision(A)) are present,
+    the solver will compute the loss twice and the relation graph becomes cyclic, which can cause
+    issues during environment creation. Deduplication or cycle detection should be addressed at a
+    higher level.
     """
 
     def __init__(

isaaclab_arena/tests/test_bounding_box.py

@@ -9,10 +9,6 @@
 
 from isaaclab_arena.utils.bounding_box import AxisAlignedBoundingBox
 
-# =============================================================================
-# Single-env tests (N=1, properties return (1, 3) or (1,) tensors)
-# =============================================================================
-
 
 def test_bounding_box_single_env_properties():
     """Single env: properties return tensors with leading dim 1."""
@@ -67,11 +63,6 @@ def test_bounding_box_single_env_get_corners_at():
     torch.testing.assert_close(corners_offset[0, 0], corners[0, 0] + torch.tensor([10.0, 0.0, 0.0]))
 
 
-# =============================================================================
-# Multi-env batch tests (N>1, properties return (N, 3) or (N,) tensors)
-# =============================================================================
-
-
 def test_bounding_box_multi_env_properties():
     """Multi-env: properties return (N, 3) or (N,) tensors."""
     aabb = AxisAlignedBoundingBox(