Make KeywordOnly an Enum

And make Hashability public

Author: hynek

src/attr/_make.py

@@ -103,7 +103,7 @@ def __reduce__(self, _none_constructor=type(None), _args=()): # noqa: B008
  return _none_constructor, _args
 
 
-class _Hashability(enum.Enum):
+class Hashability(enum.Enum):
  """
  The hashability of a class.
  """
@@ -113,6 +113,16 @@ class _Hashability(enum.Enum):
  LEAVE_ALONE = "leave_alone" # don't touch __hash__
 
 
+class KeywordOnly(enum.Enum):
+ """
+ How attributes should be treated regarding keyword-only parameters.
+ """
+
+ NO = "no" # attributes are not keyword-only
+ YES = "yes" # attributes in current class without kw_only=False are keyword-only
+ FORCE = "force" # all attributes are keyword-only
+
+
 class ClassProps(NamedTuple):
  """
  Effective class properties as derived from parameters to attr.s() or
@@ -125,14 +135,13 @@ class ClassProps(NamedTuple):
  is_slotted: bool
  has_weakref_slot: bool
  is_frozen: bool
- is_kw_only: bool
- force_kw_only: bool
+ kw_only: KeywordOnly
  collect_by_mro: bool
  init: bool
  repr: bool
  eq: bool
  order: bool
- hash: _Hashability
+ hash: Hashability
  cache_hash: bool
  match_args: bool
  str: bool
@@ -419,7 +428,6 @@ def _transform_attrs(
  these,
  auto_attribs,
  kw_only,
- force_kw_only,
  collect_by_mro,
  field_transformer,
 ) -> _Attributes:
@@ -477,7 +485,7 @@ def _transform_attrs(
 
  fca = Attribute.from_counting_attr
  own_attrs = [
- fca(attr_name, ca, kw_only, anns.get(attr_name))
+ fca(attr_name, ca, kw_only is not KeywordOnly.NO, anns.get(attr_name))
  for attr_name, ca in ca_list
  ]
 
@@ -490,7 +498,7 @@ def _transform_attrs(
  cls, {a.name for a in own_attrs}
  )
 
- if kw_only and force_kw_only:
+ if kw_only is KeywordOnly.FORCE:
  own_attrs = [a.evolve(kw_only=True) for a in own_attrs]
  base_attrs = [a.evolve(kw_only=True) for a in base_attrs]
 
@@ -708,8 +716,7 @@ def __init__(
  cls,
  these,
  auto_attribs,
- props.is_kw_only,
- props.force_kw_only,
+ props.kw_only,
  props.collect_by_mro,
  props.field_transformer,
  )
@@ -1481,28 +1488,33 @@ def wrap(cls):
  )
 
  if is_exc:
- hashability = _Hashability.LEAVE_ALONE
+ hashability = Hashability.LEAVE_ALONE
  elif hash is True:
- hashability = _Hashability.HASHABLE
+ hashability = Hashability.HASHABLE
  elif hash is False:
- hashability = _Hashability.LEAVE_ALONE
+ hashability = Hashability.LEAVE_ALONE
  elif hash is None:
  if auto_detect is True and _has_own_attribute(cls, "__hash__"):
- hashability = _Hashability.LEAVE_ALONE
+ hashability = Hashability.LEAVE_ALONE
  elif eq is True and is_frozen is True:
- hashability = _Hashability.HASHABLE
+ hashability = Hashability.HASHABLE
  elif eq is False:
- hashability = _Hashability.LEAVE_ALONE
+ hashability = Hashability.LEAVE_ALONE
  else:
- hashability = _Hashability.UNHASHABLE
+ hashability = Hashability.UNHASHABLE
  else:
  msg = "Invalid value for hash. Must be True, False, or None."
  raise TypeError(msg)
 
- if hashability is not _Hashability.HASHABLE and cache_hash:
+ if hashability is not Hashability.HASHABLE and cache_hash:
  msg = "Invalid value for cache_hash. To use hash caching, hashing must be either explicitly or implicitly enabled."
  raise TypeError(msg)
 
+ if kw_only:
+ kwo = KeywordOnly.YES if not force_kw_only else KeywordOnly.FORCE
+ else:
+ kwo = KeywordOnly.NO
+
  props = ClassProps(
  is_exception=is_exc,
  is_frozen=is_frozen,
@@ -1524,8 +1536,7 @@ def wrap(cls):
  ),
  hash=hashability,
  match_args=match_args,
- is_kw_only=kw_only,
- force_kw_only=force_kw_only,
+ kw_only=kwo,
  has_weakref_slot=weakref_slot,
  cache_hash=cache_hash,
  str=str,
@@ -1562,9 +1573,9 @@ def wrap(cls):
  if not frozen:
  builder.add_setattr()
 
- if props.hash is _Hashability.HASHABLE:
+ if props.hash is Hashability.HASHABLE:
  builder.add_hash()
- elif props.hash is _Hashability.UNHASHABLE:
+ elif props.hash is Hashability.UNHASHABLE:
  builder.make_unhashable()
 
  if props.init:

tests/test_make.py

@@ -28,14 +28,15 @@
  Attribute,
  ClassProps,
  Factory,
+ Hashability,
+ KeywordOnly,
  _AndValidator,
  _Attributes,
  _ClassBuilder,
  _CountingAttr,
  _determine_attrib_eq_order,
  _determine_attrs_eq_order,
  _determine_whether_to_implement,
- _Hashability,
  _transform_attrs,
  and_,
  fields,
@@ -183,7 +184,7 @@ def test_no_modifications(self):
  Does not attach __attrs_attrs__ to the class.
  """
  C = make_tc()
- _transform_attrs(C, None, False, False, False, True, None)
+ _transform_attrs(C, None, False, KeywordOnly.NO, True, None)
 
  assert None is getattr(C, "__attrs_attrs__", None)
 
@@ -193,7 +194,7 @@ def test_normal(self):
  """
  C = make_tc()
  attrs, _, _ = _transform_attrs(
- C, None, False, False, False, True, None
+ C, None, False, KeywordOnly.NO, True, None
  )
 
  assert ["z", "y", "x"] == [a.name for a in attrs]
@@ -208,7 +209,7 @@ class C:
  pass
 
  assert _Attributes((), [], {}) == _transform_attrs(
- C, None, False, False, False, True, None
+ C, None, False, KeywordOnly.NO, True, None
  )
 
  def test_transforms_to_attribute(self):
@@ -217,7 +218,7 @@ def test_transforms_to_attribute(self):
  """
  C = make_tc()
  attrs, base_attrs, _ = _transform_attrs(
- C, None, False, False, False, True, None
+ C, None, False, KeywordOnly.NO, True, None
  )
 
  assert [] == base_attrs
@@ -235,7 +236,7 @@ class C:
  y = attr.ib()
 
  with pytest.raises(ValueError) as e:
- _transform_attrs(C, None, False, False, False, True, None)
+ _transform_attrs(C, None, False, KeywordOnly.NO, True, None)
  assert (
  "No mandatory attributes allowed after an attribute with a "
  "default value or factory. Attribute in question: Attribute"
@@ -264,7 +265,7 @@ class C(B):
  y = attr.ib()
 
  attrs, base_attrs, _ = _transform_attrs(
- C, None, False, True, False, True, None
+ C, None, False, KeywordOnly.YES, True, None
  )
 
  assert len(attrs) == 3
@@ -280,8 +281,7 @@ class C(B):
  C,
  None,
  False,
- True,
- True, # force kw-only
+ KeywordOnly.FORCE,
  True,
  None,
  )
@@ -307,7 +307,7 @@ class C(Base):
  y = attr.ib()
 
  attrs, base_attrs, _ = _transform_attrs(
- C, {"x": attr.ib()}, False, False, False, True, None
+ C, {"x": attr.ib()}, False, KeywordOnly.NO, True, None
  )
 
  assert [] == base_attrs
@@ -540,10 +540,9 @@ class C:
  repr=True,
  eq=True,
  order=True,
- hash=_Hashability.HASHABLE,
+ hash=Hashability.HASHABLE,
  match_args=False,
- is_kw_only=True,
- force_kw_only=True,
+ kw_only=KeywordOnly.FORCE,
  has_weakref_slot=True,
  collect_by_mro=False,
  cache_hash=True,
@@ -574,10 +573,9 @@ class CDef:
  repr=True,
  eq=True,
  order=True,
- hash=_Hashability.UNHASHABLE,
+ hash=Hashability.UNHASHABLE,
  match_args=True,
- is_kw_only=False,
- force_kw_only=True,
+ kw_only=KeywordOnly.NO,
  has_weakref_slot=True,
  collect_by_mro=False,
  cache_hash=False,
@@ -2022,8 +2020,7 @@ class C:
  order=False,
  hash=False,
  match_args=True,
- is_kw_only=False,
- force_kw_only=False,
+ kw_only=KeywordOnly.NO,
  has_weakref_slot=False,
  collect_by_mro=True,
  cache_hash=False,
@@ -2059,8 +2056,7 @@ class C:
  order=False,
  hash=False,
  match_args=True,
- is_kw_only=False,
- force_kw_only=False,
+ kw_only=KeywordOnly.NO,
  has_weakref_slot=False,
  collect_by_mro=True,
  cache_hash=False,
@@ -2162,8 +2158,7 @@ def our_hasattr(obj, name, /) -> bool:
  order=False,
  hash=False,
  match_args=True,
- is_kw_only=False,
- force_kw_only=False,
+ kw_only=KeywordOnly.NO,
  has_weakref_slot=True,
  collect_by_mro=True,
  cache_hash=False,

tests/test_next_gen.py

@@ -15,7 +15,7 @@
 import attrs
 
 from attr._compat import PY_3_11_PLUS
-from attr._make import ClassProps, _Hashability
+from attr._make import ClassProps, Hashability, KeywordOnly
 
 
 @attrs.define
@@ -480,13 +480,12 @@ class C:
  is_exception=False,
  is_slotted=False,
  is_frozen=True,
- is_kw_only=True,
- force_kw_only=False,
+ kw_only=KeywordOnly.YES,
  init=True,
  repr=True,
  eq=True,
  order=True,
- hash=_Hashability.HASHABLE,
+ hash=Hashability.HASHABLE,
  match_args=False,
  has_weakref_slot=True,
  collect_by_mro=True,
@@ -517,10 +516,9 @@ class C:
  repr=True,
  eq=True,
  order=False,
- hash=_Hashability.HASHABLE, # b/c frozen
+ hash=Hashability.HASHABLE, # b/c frozen
  match_args=True,
- is_kw_only=False,
- force_kw_only=False,
+ kw_only=KeywordOnly.NO,
  has_weakref_slot=True,
  collect_by_mro=True,
  cache_hash=False,