Reland union type (#5900)

* Reapply "Add union link connection type support (#5806)" (#5889)

This reverts commit bf9a90a.

* Fix union type breaks existing type workarounds

* Add non-string test

* Add tests for hacks and non-string types

* Support python versions lower than 3.11

comfy_execution/validation.py

@@ -0,0 +1,39 @@
+from __future__ import annotations
+
+
+def validate_node_input(
+    received_type: str, input_type: str, strict: bool = False
+) -> bool:
+    """
+    received_type and input_type are both strings of the form "T1,T2,...".
+
+    If strict is True, the input_type must contain the received_type.
+      For example, if received_type is "STRING" and input_type is "STRING,INT",
+      this will return True. But if received_type is "STRING,INT" and input_type is
+      "INT", this will return False.
+
+    If strict is False, the input_type must have overlap with the received_type.
+      For example, if received_type is "STRING,BOOLEAN" and input_type is "STRING,INT",
+      this will return True.
+
+    Supports pre-union type extension behaviour of ``__ne__`` overrides.
+    """
+    # If the types are exactly the same, we can return immediately
+    # Use pre-union behaviour: inverse of `__ne__`
+    if not received_type != input_type:
+        return True
+
+    # Not equal, and not strings
+    if not isinstance(received_type, str) or not isinstance(input_type, str):
+        return False
+
+    # Split the type strings into sets for comparison
+    received_types = set(t.strip() for t in received_type.split(","))
+    input_types = set(t.strip() for t in input_type.split(","))
+
+    if strict:
+        # In strict mode, all received types must be in the input types
+        return received_types.issubset(input_types)
+    else:
+        # In non-strict mode, there must be at least one type in common
+        return len(received_types.intersection(input_types)) > 0

execution.py

@@ -16,6 +16,7 @@
 from comfy_execution.graph import get_input_info, ExecutionList, DynamicPrompt, ExecutionBlocker
 from comfy_execution.graph_utils import is_link, GraphBuilder
 from comfy_execution.caching import HierarchicalCache, LRUCache, CacheKeySetInputSignature, CacheKeySetID
+from comfy_execution.validation import validate_node_input
 from comfy.cli_args import args
 
 class ExecutionResult(Enum):
@@ -527,7 +528,6 @@ def execute(self, prompt, prompt_id, extra_data={}, execute_outputs=[]):
                 comfy.model_management.unload_all_models()
 
 
-
 def validate_inputs(prompt, item, validated):
     unique_id = item
     if unique_id in validated:
@@ -589,8 +589,8 @@ def validate_inputs(prompt, item, validated):
             r = nodes.NODE_CLASS_MAPPINGS[o_class_type].RETURN_TYPES
             received_type = r[val[1]]
             received_types[x] = received_type
-            if 'input_types' not in validate_function_inputs and received_type != type_input:
-                details = f"{x}, {received_type} != {type_input}"
+            if 'input_types' not in validate_function_inputs and not validate_node_input(received_type, type_input):
+                details = f"{x}, received_type({received_type}) mismatch input_type({type_input})"
                 error = {
                     "type": "return_type_mismatch",
                     "message": "Return type mismatch between linked nodes",

tests-unit/execution_test/validate_node_input_test.py

@@ -0,0 +1,119 @@
+import pytest
+from comfy_execution.validation import validate_node_input
+
+
+def test_exact_match():
+    """Test cases where types match exactly"""
+    assert validate_node_input("STRING", "STRING")
+    assert validate_node_input("STRING,INT", "STRING,INT")
+    assert validate_node_input("INT,STRING", "STRING,INT")  # Order shouldn't matter
+
+
+def test_strict_mode():
+    """Test strict mode validation"""
+    # Should pass - received type is subset of input type
+    assert validate_node_input("STRING", "STRING,INT", strict=True)
+    assert validate_node_input("INT", "STRING,INT", strict=True)
+    assert validate_node_input("STRING,INT", "STRING,INT,BOOLEAN", strict=True)
+
+    # Should fail - received type is not subset of input type
+    assert not validate_node_input("STRING,INT", "STRING", strict=True)
+    assert not validate_node_input("STRING,BOOLEAN", "STRING", strict=True)
+    assert not validate_node_input("INT,BOOLEAN", "STRING,INT", strict=True)
+
+
+def test_non_strict_mode():
+    """Test non-strict mode validation (default behavior)"""
+    # Should pass - types have overlap
+    assert validate_node_input("STRING,BOOLEAN", "STRING,INT")
+    assert validate_node_input("STRING,INT", "INT,BOOLEAN")
+    assert validate_node_input("STRING", "STRING,INT")
+
+    # Should fail - no overlap in types
+    assert not validate_node_input("BOOLEAN", "STRING,INT")
+    assert not validate_node_input("FLOAT", "STRING,INT")
+    assert not validate_node_input("FLOAT,BOOLEAN", "STRING,INT")
+
+
+def test_whitespace_handling():
+    """Test that whitespace is handled correctly"""
+    assert validate_node_input("STRING, INT", "STRING,INT")
+    assert validate_node_input("STRING,INT", "STRING, INT")
+    assert validate_node_input(" STRING , INT ", "STRING,INT")
+    assert validate_node_input("STRING,INT", " STRING , INT ")
+
+
+def test_empty_strings():
+    """Test behavior with empty strings"""
+    assert validate_node_input("", "")
+    assert not validate_node_input("STRING", "")
+    assert not validate_node_input("", "STRING")
+
+
+def test_single_vs_multiple():
+    """Test single type against multiple types"""
+    assert validate_node_input("STRING", "STRING,INT,BOOLEAN")
+    assert validate_node_input("STRING,INT,BOOLEAN", "STRING", strict=False)
+    assert not validate_node_input("STRING,INT,BOOLEAN", "STRING", strict=True)
+
+
+def test_non_string():
+    """Test non-string types"""
+    obj1 = object()
+    obj2 = object()
+    assert validate_node_input(obj1, obj1)
+    assert not validate_node_input(obj1, obj2)
+
+
+class NotEqualsOverrideTest(str):
+    """Test class for ``__ne__`` override."""
+
+    def __ne__(self, value: object) -> bool:
+        if self == "*" or value == "*":
+            return False
+        if self == "LONGER_THAN_2":
+            return not len(value) > 2
+        raise TypeError("This is a class for unit tests only.")
+
+
+def test_ne_override():
+    """Test ``__ne__`` any override"""
+    any = NotEqualsOverrideTest("*")
+    invalid_type = "INVALID_TYPE"
+    obj = object()
+    assert validate_node_input(any, any)
+    assert validate_node_input(any, invalid_type)
+    assert validate_node_input(any, obj)
+    assert validate_node_input(any, {})
+    assert validate_node_input(any, [])
+    assert validate_node_input(any, [1, 2, 3])
+
+
+def test_ne_custom_override():
+    """Test ``__ne__`` custom override"""
+    special = NotEqualsOverrideTest("LONGER_THAN_2")
+
+    assert validate_node_input(special, special)
+    assert validate_node_input(special, "*")
+    assert validate_node_input(special, "INVALID_TYPE")
+    assert validate_node_input(special, [1, 2, 3])
+
+    # Should fail
+    assert not validate_node_input(special, [1, 2])
+    assert not validate_node_input(special, "TY")
+
+
+@pytest.mark.parametrize(
+    "received,input_type,strict,expected",
+    [
+        ("STRING", "STRING", False, True),
+        ("STRING,INT", "STRING,INT", False, True),
+        ("STRING", "STRING,INT", True, True),
+        ("STRING,INT", "STRING", True, False),
+        ("BOOLEAN", "STRING,INT", False, False),
+        ("STRING,BOOLEAN", "STRING,INT", False, True),
+    ],
+)
+def test_parametrized_cases(received, input_type, strict, expected):
+    """Parametrized test cases for various scenarios"""
+    assert validate_node_input(received, input_type, strict) == expected