fix: provide the required_field utility

mcbeet · Sep 11, 2021 · f5cbf9c · f5cbf9c
1 parent 7bff619
commit f5cbf9c
Showing 1 changed file with 9 additions and 0 deletions.
diff --git a/beet/core/utils.py b/beet/core/utils.py
@@ -5,6 +5,7 @@
     "SENTINEL_OBJ",
     "dump_json",
     "extra_field",
+    "required_field",
     "intersperse",
     "normalize_string",
 ]
@@ -40,6 +41,14 @@ def extra_field(**kwargs: Any) -> Any:
     return field(repr=False, hash=False, compare=False, **kwargs)
 
 
+def required_field(**kwargs: Any) -> Any:
+    return field(**kwargs, default_factory=_raise_required_field)
+
+
+def _raise_required_field():
+    raise ValueError("Field required.")
+
+
 def intersperse(iterable: Iterable[T], delimitter: T) -> Iterator[T]:
     it = iter(iterable)
     yield next(it)