simplify markers fully in _compact_markers

Exploit the same cnf / dnf trick that is used in marker union

src/poetry/core/version/markers.py

@@ -702,21 +702,28 @@ def parse_marker(marker: str) -> BaseMarker:
  return markers
 
 
-def _compact_markers(tree_elements: Tree, tree_prefix: str = "") -> BaseMarker:
+def _compact_markers(
+ tree_elements: Tree, tree_prefix: str = "", top_level: bool = True
+) -> BaseMarker:
  from lark import Token
 
- groups: list[BaseMarker] = [MultiMarker()]
+ # groups is a disjunction of conjunctions
+ # eg [[A, B], [C, D]] represents "(A and B) or (C and D)"
+ groups: list[list[BaseMarker]] = [[]]
+
  for token in tree_elements:
  if isinstance(token, Token):
  if token.type == f"{tree_prefix}BOOL_OP" and token.value == "or":
- groups.append(MultiMarker())
+ groups.append([])
 
  continue
 
  if token.data == "marker":
- groups[-1] = MultiMarker.of(
- groups[-1], _compact_markers(token.children, tree_prefix=tree_prefix)
+ sub_marker = _compact_markers(
+ token.children, tree_prefix=tree_prefix, top_level=False
  )
+ groups[-1].append(sub_marker)
+
  elif token.data == f"{tree_prefix}item":
  name, op, value = token.children
  if value.type == f"{tree_prefix}MARKER_NAME":
@@ -726,27 +733,26 @@ def _compact_markers(tree_elements: Tree, tree_prefix: str = "") -> BaseMarker:
  )
 
  value = value[1:-1]
- groups[-1] = MultiMarker.of(
- groups[-1], SingleMarker(str(name), f"{op}{value}")
- )
- elif token.data == f"{tree_prefix}BOOL_OP" and token.children[0] == "or":
- groups.append(MultiMarker())
+ sub_marker = SingleMarker(str(name), f"{op}{value}")
+ groups[-1].append(sub_marker)
 
- for i, group in enumerate(reversed(groups)):
- if group.is_empty():
- del groups[len(groups) - 1 - i]
- continue
+ elif token.data == f"{tree_prefix}BOOL_OP" and token.children[0] == "or":
+ groups.append([])
 
- if isinstance(group, MultiMarker) and len(group.markers) == 1:
- groups[len(groups) - 1 - i] = group.markers[0]
+ # Combine the groups.
+ sub_markers = [MultiMarker(*group) for group in groups]
+ union = MarkerUnion(*sub_markers)
 
- if not groups:
- return EmptyMarker()
+ # This function calls itself recursively. In the inner calls we don't perform any
+ # simplification, instead doing it all only when we have the complete marker.
+ if not top_level:
+ return union
 
- if len(groups) == 1:
- return groups[0]
+ conjunction = cnf(union)
+ if not isinstance(conjunction, MultiMarker):
+ return conjunction
 
- return MarkerUnion.of(*groups)
+ return dnf(conjunction)
 
 
 def cnf(marker: BaseMarker) -> BaseMarker:

tests/packages/test_main.py

@@ -102,9 +102,9 @@ def test_dependency_from_pep_508_complex() -> None:
  assert dep.python_versions == ">=2.7 !=3.2.*"
  assert (
  str(dep.marker)
- == 'python_version >= "2.7" and python_version != "3.2" '
- 'and (sys_platform == "win32" or sys_platform == "darwin") '
- 'and extra == "foo"'
+ == 'python_version >= "2.7" and python_version != "3.2" and sys_platform =='
+ ' "win32" and extra == "foo" or python_version >= "2.7" and python_version'
+ ' != "3.2" and sys_platform == "darwin" and extra == "foo"'
  )
 
 
@@ -278,11 +278,11 @@ def test_dependency_from_pep_508_with_python_full_version() -> None:
  assert dep.name == "requests"
  assert str(dep.constraint) == "2.18.0"
  assert dep.extras == frozenset()
- assert dep.python_versions == ">=2.7 <2.8 || >=3.4 <3.5.4"
+ assert dep.python_versions == ">=2.7 <2.8 || >=3.4.0 <3.5.4"
  assert (
  str(dep.marker)
  == 'python_version >= "2.7" and python_version < "2.8" '
- 'or python_full_version >= "3.4" and python_full_version < "3.5.4"'
+ 'or python_full_version >= "3.4.0" and python_full_version < "3.5.4"'
  )
 
 

tests/packages/utils/test_utils.py

@@ -25,8 +25,8 @@
  {
  "python_version": [
  [("<", "3.6")],
- [("<", "3.6"), (">=", "3.3")],
  [("<", "3.3")],
+ [("<", "3.6"), (">=", "3.3")],
  ],
  "sys_platform": [
  [("==", "win32")],
@@ -41,10 +41,7 @@
  ' "win32" and python_version < "3.6" and python_version >= "3.3" or'
  ' sys_platform == "win32" and python_version < "3.3"'
  ),
- {
- "python_version": [[("<", "3.6")], [("<", "3.3")]],
- "sys_platform": [[("==", "win32")]],
- },
+ {"python_version": [[("<", "3.6")]], "sys_platform": [[("==", "win32")]]},
  ),
  (
  'python_version == "2.7" or python_version == "2.6"',

tests/version/test_markers.py

@@ -1370,6 +1370,16 @@ def test_empty_marker_is_found_in_complex_intersection(
  assert m2.intersect(m1).is_empty()
 
 
+def test_empty_marker_is_found_in_complex_parse() -> None:
+ marker = parse_marker(
+ '(python_implementation != "pypy" or python_version != "3.6") and '
+ '((python_implementation != "pypy" and python_version != "3.6") or'
+ ' (python_implementation == "pypy" and python_version == "3.6")) and '
+ '(python_implementation == "pypy" or python_version == "3.6")'
+ )
+ assert marker.is_empty()
+
+
 @pytest.mark.parametrize(
  "python_version, python_full_version, "
  "expected_intersection_version, expected_union_version",