Validate DeMemWM future memory selection

.exp_artifact/dememwm_future_memory_selection_plan.md

@@ -405,7 +405,7 @@ Make DeMemWM memory streams self-only
 
 ## Substep 5: Final Integration Validation
 
-Status: `[ ]`
+Status: `[x]`
 
 Goal:
 

datasets/video/memory_selection.py

@@ -867,8 +867,6 @@ def select_memory_indices(
     else:
         anchor_stop = min(target_start, max(anchor_start, int(anchor_candidate_stop)))
     anchor_candidates = np.arange(anchor_start, anchor_stop, dtype=np.int64)
-    if len(dynamic) > 0:
-        anchor_candidates = anchor_candidates[~np.isin(anchor_candidates, dynamic)]
     anchor = _select_anchor(anchor_candidates, counts["anchor"], cfg, poses=poses)
 
     revisit = _select_revisit(

tests/test_dememwm_latent_dataset.py

@@ -364,6 +364,30 @@ class MemorySelectionTests(unittest.TestCase):
         for key in ("anchor", "dynamic", "revisit"):
             self.assertTrue(np.all(indices[key][masks[key]] < 6))
 
+    def test_anchor_can_duplicate_recent_dynamic_when_selected(self):
+        poses = _poses(8)
+        cfg = _selection_cfg(
+            max_anchor_frames=1,
+            max_dynamic_frames=1,
+            max_revisit_frames=0,
+            dynamic=_dynamic_cfg("recent"),
+        )
+
+        indices, masks = select_memory_indices(
+            poses,
+            np.array([6]),
+            cfg,
+            split="training",
+            anchor_candidate_start=5,
+            anchor_candidate_stop=6,
+        )
+
+        self.assertEqual(indices["anchor"].tolist(), [5])
+        self.assertEqual(indices["dynamic"].tolist(), [5])
+        self.assertEqual(masks["anchor"].tolist(), [True])
+        self.assertEqual(masks["dynamic"].tolist(), [True])
+        self.assertTrue(np.all(indices["dynamic"][masks["dynamic"]] < 6))
+
     def test_anchor_selection_is_context_bounded_farthest_point(self):
         poses = _poses(10)
         cfg = _selection_cfg(
@@ -1376,7 +1400,7 @@ class DeMemWMLatentDatasetTests(unittest.TestCase):
 
         self.assertEqual(dataset.context_length, 4)
         self.assertEqual(len(dataset), 112 - (100 + 4 + 3) + 1)
-        self.assertEqual(sample["frame_indices"].tolist(), [106, 107, 108, 102, 103, 104, 105])
+        self.assertEqual(sample["frame_indices"].tolist(), [106, 107, 108, 102, 105, 104, 105])
         self.assertTrue(sample["memory_masks"]["anchor"].all().item())
         self.assertTrue(sample["memory_masks"]["dynamic"].all().item())
         self.assertEqual(tuple(sample["memory_masks"]["revisit"].shape), (0,))