fix(bindings): Update according to PR #2460

Resolves: flyteorg/flyte#5321
Signed-off-by: Chi-Sheng Liu <[email protected]>

flytekit/core/promise.py

@@ -690,7 +690,6 @@ def binding_data_from_python_std(
     t_value: Any,
     t_value_type: type,
     nodes: List[Node],
-    is_union_type_variants_expanded: bool = True,
 ) -> _literals_models.BindingData:
     # This handles the case where the given value is the output of another task
     if isinstance(t_value, Promise):
@@ -713,7 +712,6 @@ def binding_data_from_python_std(
         # If it is a container type, then we need to iterate over the variants in the Union type, try each one. This is
         # akin to what the Type Engine does when it finds a Union type (see the UnionTransformer), but we can't rely on
         # that in this case, because of the mix and match of realized values, and Promises.
-    elif t_value is not None and is_union_type_variants_expanded and expected_literal_type.union_type is not None:
         for i in range(len(expected_literal_type.union_type.variants)):
             try:
                 lt_type = expected_literal_type.union_type.variants[i]
@@ -780,7 +778,6 @@ def binding_from_python_std(
     expected_literal_type: _type_models.LiteralType,
     t_value: Any,
     t_value_type: type,
-    is_union_type_variants_expanded: bool = True,
 ) -> Tuple[_literals_models.Binding, List[Node]]:
     nodes: List[Node] = []
     binding_data = binding_data_from_python_std(
@@ -789,7 +786,6 @@ def binding_from_python_std(
         t_value,
         t_value_type,
         nodes,
-        is_union_type_variants_expanded=is_union_type_variants_expanded,
     )
     return _literals_models.Binding(var=var_name, binding=binding_data), nodes
 
@@ -1082,7 +1078,6 @@ def create_and_link_node(
 
     for k in sorted(interface.inputs):
         var = typed_interface.inputs[k]
-        is_default_arg_used = False
         if var.type.simple == SimpleType.NONE:
             raise TypeError("Arguments do not have type annotation")
         if k not in kwargs:
@@ -1096,7 +1091,6 @@ def create_and_link_node(
                 if not isinstance(default_val, Hashable):
                     raise _user_exceptions.FlyteAssertion("Cannot use non-hashable object as default argument")
                 kwargs[k] = default_val
-                is_default_arg_used = True
             else:
                 error_msg = f"Input {k} of type {interface.inputs[k]} was not specified for function {entity.name}"
                 raise _user_exceptions.FlyteAssertion(error_msg)
@@ -1116,7 +1110,6 @@ def create_and_link_node(
                 expected_literal_type=var.type,
                 t_value=v,
                 t_value_type=interface.inputs[k],
-                is_union_type_variants_expanded=not is_default_arg_used,
             )
             bindings.append(b)
             nodes.extend(n)

tests/flytekit/unit/core/test_serialization.py

@@ -623,7 +623,15 @@ def wf_with_sub_wf() -> tuple[typing.Optional[int], typing.Optional[int]]:
         ),
     )
     assert wf_with_input_spec.template.nodes[0].inputs[0].binding.value == Scalar(
-        primitive=Primitive(integer=input_val)
+        union=Union(
+            value=Literal(
+                scalar=Scalar(primitive=Primitive(integer=input_val)),
+            ),
+            stored_type=LiteralType(
+                simple=SimpleType.INTEGER,
+                structure=TypeStructure(tag="int"),
+            ),
+        ),
     )
 
     output_type = LiteralType(
@@ -685,7 +693,15 @@ def wf_with_sub_wf() -> tuple[typing.Optional[int], typing.Optional[int]]:
         ),
     )
     assert wf_with_input_spec.template.nodes[0].inputs[0].binding.value == Scalar(
-        primitive=Primitive(integer=input_val)
+        union=Union(
+            value=Literal(
+                scalar=Scalar(primitive=Primitive(integer=input_val)),
+            ),
+            stored_type=LiteralType(
+                simple=SimpleType.INTEGER,
+                structure=TypeStructure(tag="int"),
+            ),
+        ),
     )
 
     output_type = LiteralType(