Rename new function to set_enum_based_on_type

This function only support setting the enum field, and it doesn't appear
likely that we will want to set other fields in future, so make the name
more specific. Additionally, add a docstring, and refactor the function
to use the early-return pattern now adding other metadata is ruled out.

Signed-off-by: Alice Purcell <[email protected]>

src/hera/shared/_type_util.py

@@ -83,11 +83,16 @@ def get_workflow_annotation(annotation: Any) -> Optional[Union[Artifact, Paramet
     return metadata[0]
 
 
-def add_metadata_from_type(parameter: Parameter, annotation: Any) -> None:
-    if not parameter.enum:
-        type_ = unwrap_annotation(annotation)
-        if get_origin(type_) is Literal:
-            parameter.enum = list(get_args(type_))
+def set_enum_based_on_type(parameter: Parameter, annotation: Any) -> None:
+    """Sets the enum field of a Parameter based on its type annotation.
+
+    Currently, only supports Literals.
+    """
+    if parameter.enum:
+        return
+    type_ = unwrap_annotation(annotation)
+    if get_origin(type_) is Literal:
+        parameter.enum = list(get_args(type_))
 
 
 def construct_io_from_annotation(python_name: str, annotation: Any) -> Union[Parameter, Artifact]:
@@ -107,7 +112,7 @@ def construct_io_from_annotation(python_name: str, annotation: Any) -> Union[Par
 
     io.name = io.name or python_name
     if isinstance(io, Parameter):
-        add_metadata_from_type(io, annotation)
+        set_enum_based_on_type(io, annotation)
 
     return io
 

src/hera/workflows/script.py

@@ -48,11 +48,11 @@
 )
 from hera.shared._pydantic import _PYDANTIC_VERSION, root_validator, validator
 from hera.shared._type_util import (
-    add_metadata_from_type,
     construct_io_from_annotation,
     get_workflow_annotation,
     is_subscripted,
     origin_type_issupertype,
+    set_enum_based_on_type,
 )
 from hera.shared.serialization import serialize
 from hera.workflows._context import _context
@@ -380,7 +380,7 @@ def _get_parameters_from_callable(source: Callable) -> List[Parameter]:
             default = MISSING
 
         param = Parameter(name=p.name, default=default)
-        add_metadata_from_type(param, p.annotation)
+        set_enum_based_on_type(param, p.annotation)
         parameters.append(param)
 
     return parameters