fix: group chunks for placement from different partitions to avoid du…

…plicates (#880)

bsb/placement/strategy.py

@@ -133,10 +133,11 @@ def queue(self, pool, chunk_size):
                 *(pool.get_submissions_of(strat) for strat in self.get_deps())
             )
         )
-        for p in self.partitions:
-            chunks = p.to_chunks(chunk_size)
-            for chunk in chunks:
-                job = pool.queue_placement(self, Chunk(chunk, chunk_size), deps=deps)
+        chunks = np.unique(
+            np.concatenate([p.to_chunks(chunk_size) for p in self.partitions]), axis=0
+        )
+        for chunk in chunks:
+            job = pool.queue_placement(self, Chunk(chunk, chunk_size), deps=deps)
 
     def is_entities(self):
         return "entities" in self.__class__.__dict__ and self.__class__.entities

tests/test_placement.py

@@ -253,14 +253,28 @@ class TestPlacementStrategies(
     def test_random_placement(self):
         cfg = get_test_config("single")
         network = Scaffold(cfg, self.storage)
+        network.compile(clear=True)
+        ps = network.get_placement_set("test_cell")
+        self.assertEqual(40, len(ps), "fixed count random placement broken")
+
+    def test_regression_issue_879(self):
+        """
+        If different partitions share chunks, these chunks should be dealt
+        only once by the placement strategy.
+        """
+        cfg = get_test_config("single")
+        cfg.partitions.add("test_layer2", {"thickness": 50.0})
         cfg.placement["test_placement"] = dict(
             strategy="bsb.placement.RandomPlacement",
             cell_types=["test_cell"],
-            partitions=["test_layer"],
+            partitions=["test_layer", "test_layer2"],
         )
+        network = Scaffold(cfg, self.storage)
         network.compile(clear=True)
         ps = network.get_placement_set("test_cell")
-        self.assertEqual(40, len(ps), "fixed count random placement broken")
+        self.assertEqual(
+            40, len(ps), "multi partitions fixed count random placement broken"
+        )
 
     def test_fixed_pos(self):
         cfg = Configuration.default(