def evaluate_forwardref(ref: ForwardRef, globalns: Dict,
localns: Dict) -> Any:
"""Evaluate a forward reference."""
if sys.version_info > (3, 9):
return ref._evaluate(globalns, localns, frozenset())
else:
return ref._evaluate(globalns, localns)
def evaluate(annotation: Any, globalns: Dict, localns: Dict) -> Any:
"""Evaluate unresolved type annotation."""
try:
if isinstance(annotation, str):
ref = ForwardRef(annotation, True)
annotation = evaluate_forwardref(ref, globalns, localns)
if isinstance(annotation, ForwardRef):
annotation = evaluate_forwardref(ref, globalns, localns)
elif isinstance(annotation, str):
# might be a ForwardRef'ed annotation in overloaded functions
ref = ForwardRef(annotation, True)
annotation = evaluate_forwardref(ref, globalns, localns)
except (NameError, TypeError):
# failed to evaluate type. skipped.
pass
return annotation
