Add native ComfyUI list output converter

CHANGELOG.md

@@ -1,5 +1,11 @@
 # Changelog
 
+## 1.1.0 - 2026-08-27
+
+- Add `List To ComfyUI List`, which exposes an ETK `LIST` through ComfyUI's
+  native list-mapped output contract without changing the contained items.
+- Preserve all nine historical `*FromListIdx` workflow class IDs and behavior.
+
 ## 1.0.0 - 2026-08-26
 
 - Extract all historical `*FromListIdx` selectors into one standalone pack.

README.md

@@ -1,6 +1,7 @@
 # ETK From List Index
 
-A standalone ComfyUI node pack for selecting one item from a list by index.
+A standalone ComfyUI node pack for selecting one item from a list by index and
+converting an ETK `LIST` value into a native ComfyUI list-mapped output.
 
 The pack preserves the historical workflow class IDs, input socket names,
 output order, categories, and selection behavior previously supplied by
@@ -18,13 +19,19 @@ replacement or rewiring.
 - `BytesFromListIdx`
 - `IntFromListIdx`
 - `FloatFromListIdx`
+- `ETKListToComfyList` (`List To ComfyUI List`)
+
+`List To ComfyUI List` returns the contained items through ComfyUI's native
+list-output contract. A downstream node that does not use `INPUT_IS_LIST` is
+therefore executed once for every item, instead of receiving one Python list
+object.
 
 ## Install
 
 Install the immutable Registry release with Comfy CLI:
 
 ```bash
-comfy node install etk-from-list-index@1.0.0
+comfy node install etk-from-list-index@1.1.0
 ```
 
 New Registry releases have a short pending security-scan window. During that

__init__.py

@@ -5,6 +5,7 @@ from .nodes import (
     BytesFromListIdx,
     ConditioningFromListIdx,
     DictFromListIdx,
+    ETKListToComfyList,
     FloatFromListIdx,
     ImageFromListIdx,
     IntFromListIdx,
@@ -23,10 +24,12 @@ NODE_CLASS_MAPPINGS = {
     "BytesFromListIdx": BytesFromListIdx,
     "IntFromListIdx": IntFromListIdx,
     "FloatFromListIdx": FloatFromListIdx,
+    "ETKListToComfyList": ETKListToComfyList,
 }
 
 NODE_DISPLAY_NAME_MAPPINGS = {
     "AudioFromListIdx": "Audio From List Index",
+    "ETKListToComfyList": "List To ComfyUI List",
 }
 
 __all__ = [
@@ -34,6 +37,7 @@ __all__ = [
     "BytesFromListIdx",
     "ConditioningFromListIdx",
     "DictFromListIdx",
+    "ETKListToComfyList",
     "FloatFromListIdx",
     "ImageFromListIdx",
     "IntFromListIdx",

nodes.py

@@ -6,6 +6,37 @@ from collections.abc import Mapping
 from copy import deepcopy
 
 
+class AnyType(str):
+    """ComfyUI wildcard socket type for a list whose item type is not fixed."""
+
+    def __ne__(self, other):
+        return False
+
+
+ANY_TYPE = AnyType("*")
+
+
+class ETKListToComfyList:
+    @classmethod
+    def INPUT_TYPES(cls):
+        return {
+            "required": {
+                "items": ("LIST", {"default": []}),
+            }
+        }
+
+    RETURN_TYPES = (ANY_TYPE,)
+    RETURN_NAMES = ("items",)
+    OUTPUT_IS_LIST = (True,)
+    FUNCTION = "convert"
+    CATEGORY = "ETK/List"
+
+    def convert(self, items):
+        if not isinstance(items, list):
+            raise TypeError(f"items must be a LIST, got {type(items).__name__}")
+        return (items,)
+
+
 class ImageFromListIdx:
     @classmethod
     def INPUT_TYPES(cls):

pyproject.toml

@@ -1,7 +1,7 @@
 [project]
 name = "etk-from-list-index"
-version = "1.0.0"
-description = "Workflow-compatible list-index selector nodes for ComfyUI images, latents, conditioning, audio, and primitive values."
+version = "1.1.0"
+description = "Workflow-compatible ComfyUI list-index selectors and ETK LIST to native list-output conversion."
 license = { file = "LICENSE" }
 requires-python = ">=3.10"
 dependencies = []

tests/test_node_contract.py

@@ -29,16 +29,37 @@ EXPECTED_IDS = {
     "BytesFromListIdx",
     "IntFromListIdx",
     "FloatFromListIdx",
+    "ETKListToComfyList",
 }
 
 
 def test_exact_workflow_ids_are_registered():
     assert set(PACKAGE.NODE_CLASS_MAPPINGS) == EXPECTED_IDS
     assert PACKAGE.NODE_DISPLAY_NAME_MAPPINGS == {
-        "AudioFromListIdx": "Audio From List Index"
+        "AudioFromListIdx": "Audio From List Index",
+        "ETKListToComfyList": "List To ComfyUI List",
     }
 
 
+def test_etk_list_to_comfy_list_uses_native_list_output_contract():
+    node = PACKAGE.ETKListToComfyList
+    source = ["first", {"second": 2}, 3]
+
+    assert node.INPUT_TYPES() == {
+        "required": {"items": ("LIST", {"default": []})}
+    }
+    assert node.RETURN_NAMES == ("items",)
+    assert node.OUTPUT_IS_LIST == (True,)
+    assert node.CATEGORY == "ETK/List"
+    assert node().convert(source) == (source,)
+    assert node().convert(source)[0] is source
+    assert node().convert([]) == ([],)
+    assert (node.RETURN_TYPES[0] != "IMAGE") is False
+
+    with pytest.raises(TypeError, match="items must be a LIST"):
+        node().convert("not-a-list")
+
+
 def test_etk_schema_and_selection_contracts():
     image = PACKAGE.ImageFromListIdx
     latent = PACKAGE.LatentFromListIdx