From c5c8df097371af1da1f05022877aabe2ba96f77a Mon Sep 17 00:00:00 2001
From: Nicolas Predella <nicolas@predella.me>
Date: Tue, 13 Oct 2026 16:22:23 +0300
Subject: [PATCH] flattening in join

---
 core/nodeslicer/nodes/base.py | 45 +++++++++++++++++++++++++++++++++--
 tests/test_lists.py           | 33 +++++++++++++++++++++++++
 2 files changed, 76 insertions(+), 2 deletions(-)

diff --git a/core/nodeslicer/nodes/base.py b/core/nodeslicer/nodes/base.py
index 734a557..b47ea9b 100644
--- a/core/nodeslicer/nodes/base.py
+++ b/core/nodeslicer/nodes/base.py
@@ -164,13 +164,54 @@ class SliceNodeListJoiner(SliceNode):
     def evaluate_output(self, socket_name: str, **kwargs) -> list[Any]:
         from ....infra.blender.list_utils import flatten_list, is_list_data
         items: list[Any] = []
-        raw_inputs = self.resolve_multi_input(self.socket_label)
-        for val in raw_inputs:
+
+        if "resolve_multi_input" in self.__dict__:
+            raw_inputs = self.resolve_multi_input(self.socket_label)
+            for val in raw_inputs:
+                if val is not None:
+                    if is_list_data(val):
+                        items.extend(flatten_list(val))
+                    else:
+                        items.append(val)
+            return items
+
+        target_inputs = [
+            i for i in getattr(self, "inputs", [])
+            if getattr(i, "name", "") == self.socket_label or getattr(i, "identifier", "").startswith(f"{self.socket_label}_ms_in_")
+        ]
+
+        if not target_inputs:
+            raw_inputs = self.resolve_multi_input(self.socket_label)
+            for val in raw_inputs:
+                if val is not None:
+                    if is_list_data(val):
+                        items.extend(flatten_list(val))
+                    else:
+                        items.append(val)
+            return items
+
+        cache = getattr(self, "_current_cache", None)
+        visited = getattr(self, "_current_visited", None)
+        from ....infra.blender.blender_slice_nodes_generic import resolve_input
+
+        for inp in target_inputs:
+            if not getattr(inp, "is_linked", False):
+                val = getattr(inp, "value", None)
+                if val is None or val == "":
+                    val = getattr(inp, "default_value", None)
+                if val is None or val == "":
+                    continue
+                if type(val).__name__ == "SlicePaths" and len(val) == 0:
+                    continue
+            else:
+                val = resolve_input(inp, cache=cache, visited=visited, fieldname=self.socket_label, node=self)
+
             if val is not None:
                 if is_list_data(val):
                     items.extend(flatten_list(val))
                 else:
                     items.append(val)
+
         return items
 
 class ExecSliceNode(SliceNode):
diff --git a/tests/test_lists.py b/tests/test_lists.py
index 8fbbe95..0373e31 100644
--- a/tests/test_lists.py
+++ b/tests/test_lists.py
@@ -383,6 +383,39 @@ class TestNodeEvaluationsWithLists(unittest.TestCase):
         g_node.resolve_multi_input = lambda label: [["G1 X1"], "G1 X2"]
         self.assertEqual(g_node.evaluate_output("Gcode"), ["G1 X1", "G1 X2"])
 
+    def test_x_to_list_flattens_nested_and_incoming_lists(self):
+        from NodeSlicer.core.nodeslicer.nodes.inputs import SLICENODE_ObjectsToList
+        from NodeSlicer.core.nodeslicer.nodes.mesh import SLICENODE_MeshesToList
+        from NodeSlicer.core.nodeslicer.nodes.path import SLICENODE_PathsToList
+        from NodeSlicer.core.nodeslicer.nodes.gcode import SLICENODE_GcodesToList
+
+        # ObjectsToList with nested lists and single elements
+        obj1, obj2, obj3, obj4 = DummyObject("O1"), DummyObject("O2"), DummyObject("O3"), DummyObject("O4")
+        o_node = SLICENODE_ObjectsToList()
+        o_node.resolve_multi_input = lambda label: [[obj1, obj2], obj3, [obj4]]
+        self.assertEqual(o_node.evaluate_output("Objects"), [obj1, obj2, obj3, obj4])
+
+        # MeshesToList with nested lists
+        sc1 = SlicingCollection([], "M1")
+        sc2 = SlicingCollection([], "M2")
+        sc3 = SlicingCollection([], "M3")
+        m_node = SLICENODE_MeshesToList()
+        m_node.resolve_multi_input = lambda label: [[sc1, sc2], [sc3]]
+        self.assertEqual(m_node.evaluate_output("Meshes"), [sc1, sc2, sc3])
+
+        # PathsToList with list input and single input
+        sp1 = SlicePaths([np.array([[0, 0, 0], [1, 1, 0]], dtype=np.float64)])
+        sp2 = SlicePaths([np.array([[2, 2, 0], [3, 3, 0]], dtype=np.float64)])
+        sp3 = SlicePaths([np.array([[4, 4, 0], [5, 5, 0]], dtype=np.float64)])
+        p_node = SLICENODE_PathsToList()
+        p_node.resolve_multi_input = lambda label: [[sp1, sp2], sp3]
+        self.assertEqual(p_node.evaluate_output("Paths"), [sp1, sp2, sp3])
+
+        # GcodesToList with list input and single input
+        g_node = SLICENODE_GcodesToList()
+        g_node.resolve_multi_input = lambda label: [["G1 X1", "G1 X2"], "G1 X3", ["G1 X4", "G1 X5"]]
+        self.assertEqual(g_node.evaluate_output("Gcode"), ["G1 X1", "G1 X2", "G1 X3", "G1 X4", "G1 X5"])
+
     def test_join_mesh_flattens_lists(self):
         from NodeSlicer.core.nodeslicer.nodes.mesh import SLICENODE_JoinMesh