solver: fix a special case with unconditional dependency of an extra (#…

…7175)

Co-authored-by: David Hotham <david.hotham@blueyonder.co.uk>

src/poetry/puzzle/provider.py

@@ -20,6 +20,7 @@
 from poetry.core.constraints.version import Version
 from poetry.core.packages.utils.utils import get_python_constraint_from_marker
 from poetry.core.version.markers import AnyMarker
+from poetry.core.version.markers import EmptyMarker
 from poetry.core.version.markers import MarkerUnion
 
 from poetry.inspection.info import PackageInfo
@@ -946,20 +947,13 @@ def _merge_dependencies_by_constraint(
  for dep in dependencies:
  by_constraint[dep.constraint].append(dep)
  for constraint, _deps in by_constraint.items():
- new_markers = []
- for dep in _deps:
- marker = dep.marker.without_extras()
- if marker.is_any():
- # No marker or only extras
- continue
-
- new_markers.append(marker)
-
- if not new_markers:
- continue
+ new_markers = [dep.marker for dep in _deps]
 
  dep = _deps[0]
- dep.marker = dep.marker.union(MarkerUnion(*new_markers))
+
+ # Union with EmptyMarker is to make sure we get the benefit of marker
+ # simplifications.
+ dep.marker = MarkerUnion(*new_markers).union(EmptyMarker())
  by_constraint[constraint] = [dep]
 
  return [value[0] for value in by_constraint.values()]

src/poetry/puzzle/solver.py

@@ -181,8 +181,16 @@ def _solve(self) -> tuple[list[Package], list[int]]:
  if _package.name == dep.name:
  continue
 
- if dep not in _package.requires:
+ try:
+ index = _package.requires.index(dep)
+ except ValueError:
  _package.add_dependency(dep)
+ else:
+ _dep = _package.requires[index]
+ if _dep.marker != dep.marker:
+ # marker of feature package is more accurate
+ # because it includes relevant extras
+ _dep.marker = dep.marker
  else:
  final_packages.append(package)
  depths.append(results[package])

tests/puzzle/test_solver.py

@@ -791,6 +791,45 @@ def test_solver_merge_extras_into_base_package_multiple_repos_fixes_5727(
  assert len(ops[0].package.requires) == 0, "a should not require itself"
 
 
+def test_solver_returns_extras_if_excluded_by_markers_without_extras(
+ solver: Solver, repo: Repository, package: ProjectPackage
+):
+ package.add_dependency(
+ Factory.create_dependency("A", {"version": "*", "extras": ["foo"]})
+ )
+
+ package_a = get_package("A", "1.0")
+ package_b = get_package("B", "1.0")
+
+ # mandatory dependency with marker
+ dep = get_dependency("B", "^1.0")
+ dep.marker = parse_marker("sys_platform != 'linux'")
+ package_a.add_dependency(dep)
+
+ # optional dependency with same constraint and no marker except for extra
+ dep = get_dependency("B", "^1.0", optional=True)
+ dep.marker = parse_marker("extra == 'foo'")
+ package_a.extras = {"foo": [dep]}
+ package_a.add_dependency(dep)
+
+ repo.add_package(package_a)
+ repo.add_package(package_b)
+
+ transaction = solver.solve()
+
+ ops = check_solver_result(
+ transaction,
+ [
+ {"job": "install", "package": package_b},
+ {"job": "install", "package": package_a},
+ ],
+ )
+ assert (
+ str(ops[1].package.requires[0].marker)
+ == 'sys_platform != "linux" or extra == "foo"'
+ )
+
+
 def test_solver_returns_prereleases_if_requested(
  solver: Solver, repo: Repository, package: ProjectPackage
 ):