(joe) address requirement creation from other paths

news/10550.feature.rst

@@ -0,0 +1 @@
+Improve performance of dependency resolution.

src/pip/_internal/resolution/resolvelib/factory.py

@@ -18,8 +18,10 @@
     cast,
 )
 
-from pip._vendor.packaging.requirements import InvalidRequirement
-from pip._vendor.packaging.requirements import Requirement as PackagingRequirement
+from pip._vendor.packaging.requirements import (
+    InvalidRequirement,
+    get_or_create_requirement,
+)
 from pip._vendor.packaging.specifiers import SpecifierSet
 from pip._vendor.packaging.utils import NormalizedName, canonicalize_name
 from pip._vendor.resolvelib import ResolutionImpossible
@@ -365,7 +367,7 @@ def find_candidates(
         # If the current identifier contains extras, add explicit candidates
         # from entries from extra-less identifier.
         with contextlib.suppress(InvalidRequirement):
-            parsed_requirement = PackagingRequirement(identifier)
+            parsed_requirement = get_or_create_requirement(identifier)
             explicit_candidates.update(
                 self._iter_explicit_candidates_from_base(
                     requirements.get(parsed_requirement.name, ()),

tests/unit/test_req.py

@@ -657,13 +657,15 @@ def test_parse_editable_local_extras(
         {"bar", "baz"},
     )
 
+
 def test_get_or_create_caching() -> None:
     """test caching of get_or_create requirement"""
     teststr = "affinegap==1.10"
     assert get_or_create_requirement(teststr) == Requirement(teststr)
-    assert not(get_or_create_requirement(teststr) is Requirement(teststr))
+    assert not (get_or_create_requirement(teststr) is Requirement(teststr))
     assert get_or_create_requirement(teststr) is get_or_create_requirement(teststr)
 
+
 def test_exclusive_environment_markers() -> None:
     """Make sure RequirementSet accepts several excluding env markers"""
     eq36 = install_req_from_line("Django>=1.6.10,<1.7 ; python_version == '3.6'")