further simplification

src/poetry/core/packages/utils/utils.py

@@ -179,8 +179,8 @@ def add_constraint(
  for i, sub_marker in enumerate(conjunctions):
  if isinstance(sub_marker, MultiMarker):
  for m in sub_marker.markers:
- if isinstance(m, SingleMarker):
-  add_constraint(m.name, (m.operator, m.value), i)
+ assert isinstance(m, SingleMarker)
+ add_constraint(m.name, (m.operator, m.value), i)
  elif isinstance(sub_marker, SingleMarker):
  add_constraint(sub_marker.name, (sub_marker.operator, sub_marker.value), i)
 

src/poetry/core/version/markers.py

@@ -444,31 +444,18 @@ def union(self, other: BaseMarker) -> BaseMarker:
 
  def union_simplify(self, other: BaseMarker) -> BaseMarker | None:
  """
- In contrast to the standard union method, which prefers to return
- a MarkerUnion of MultiMarkers, this version prefers to return
- a MultiMarker of MarkerUnions.
+ Finds a couple of easy simplifications for union on MultiMarkers:
 
- The rationale behind this approach is to find additional simplifications.
- In order to avoid endless recursions, this method returns None
- if it cannot find a simplification.
+ - union with any marker that appears as part of the multi is just that
+ marker
+
+ - union between two multimarkers where one is contained by the other is just
+ the larger of the two
  """
- if isinstance(other, SingleMarker):
- new_markers = []
- for marker in self._markers:
- union = marker.union(other)
- if not union.is_any():
- new_markers.append(union)
-
- if len(new_markers) == 1:
- return new_markers[0]
-
- if other in new_markers and all(
- other == m or isinstance(m, MarkerUnion) and other in m.markers
- for m in new_markers
- ):
- return other
+ if other in self._markers:
+ return other
 
- elif isinstance(other, MultiMarker):
+ if isinstance(other, MultiMarker):
  common_markers = [
  marker for marker in self.markers if marker in other.markers
  ]
@@ -485,13 +472,6 @@ def union_simplify(self, other: BaseMarker) -> BaseMarker | None:
  if not other_unique_markers:
  return other
 
- if common_markers:
- unique_union = MultiMarker(*unique_markers).union(
- MultiMarker(*other_unique_markers)
- )
- if not isinstance(unique_union, MarkerUnion):
- return MultiMarker(*common_markers).intersect(unique_union)
-
  return None
 
  def validate(self, environment: dict[str, Any] | None) -> bool:

tests/packages/utils/test_utils.py

@@ -41,7 +41,10 @@
  ' "win32" and python_version < "3.6" and python_version >= "3.3" or'
  ' sys_platform == "win32" and python_version < "3.3"'
  ),
- {"python_version": [[("<", "3.6")]], "sys_platform": [[("==", "win32")]]},
+ {
+ "python_version": [[("<", "3.6")], [("<", "3.3")]],
+ "sys_platform": [[("==", "win32")]],
+ },
  ),
  (
  'python_version == "2.7" or python_version == "2.6"',