Move constraints from factory to provider

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

@@ -6,6 +6,7 @@ if MYPY_CHECK_RUNNING:
     from typing import Optional, Sequence, Set
 
     from pip._internal.req.req_install import InstallRequirement
+    from pip._vendor.packaging.specifiers import SpecifierSet
     from pip._vendor.packaging.version import _BaseVersion
 
 
@@ -23,8 +24,8 @@ class Requirement(object):
         # type: () -> str
         raise NotImplementedError("Subclass should override")
 
-    def find_matches(self):
-        # type: () -> Sequence[Candidate]
+    def find_matches(self, constraints):
+        # type: (Sequence[SpecifierSet]) -> Sequence[Candidate]
         raise NotImplementedError("Subclass should override")
 
     def is_satisfied_by(self, candidate):

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

@@ -21,7 +21,7 @@ from .requirements import (
 )
 
 if MYPY_CHECK_RUNNING:
-    from typing import Dict, Iterator, List, Optional, Set, Tuple, TypeVar
+    from typing import Dict, Iterator, Optional, Set, Tuple, TypeVar
 
     from pip._vendor.packaging.specifiers import SpecifierSet
     from pip._vendor.packaging.version import _BaseVersion
@@ -79,8 +79,6 @@ class Factory(object):
         else:
             self._installed_dists = {}
 
-        self._constraints = {}  # type: Dict[str,List[SpecifierSet]]
-
     def _make_candidate_from_dist(
         self,
         dist,  # type: Distribution

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

@@ -3,7 +3,9 @@ from pip._vendor.resolvelib.providers import AbstractProvider
 from pip._internal.utils.typing import MYPY_CHECK_RUNNING
 
 if MYPY_CHECK_RUNNING:
-    from typing import Any, Optional, Sequence, Tuple, Union
+    from typing import Any, Dict, List, Optional, Sequence, Tuple, Union
+
+    from pip._vendor.packaging.specifiers import SpecifierSet
 
     from pip._internal.req.req_install import InstallRequirement
 
@@ -15,10 +17,12 @@ class PipProvider(AbstractProvider):
     def __init__(
         self,
         factory,  # type: Factory
+        constraints,  # type: Dict[str,List[SpecifierSet]]
         ignore_dependencies,  # type: bool
     ):
         # type: (...) -> None
         self._factory = factory
+        self._constraints = constraints
         self._ignore_dependencies = ignore_dependencies
 
     def get_install_requirement(self, c):
@@ -41,7 +45,8 @@ class PipProvider(AbstractProvider):
 
     def find_matches(self, requirement):
         # type: (Requirement) -> Sequence[Candidate]
-        return requirement.find_matches()
+        constraints = self._constraints.get(requirement.name, [])
+        return requirement.find_matches(constraints)
 
     def is_satisfied_by(self, requirement, candidate):
         # type: (Requirement, Candidate) -> bool

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

@@ -35,9 +35,9 @@ class ExplicitRequirement(Requirement):
         # No need to canonicalise - the candidate did this
         return self.candidate.name
 
-    def find_matches(self):
-        # type: () -> Sequence[Candidate]
-        if self.name in self._factory._constraints:
+    def find_matches(self, constraints):
+        # type: (Sequence[SpecifierSet]) -> Sequence[Candidate]
+        if constraints:
             raise InstallationError(
                 "Could not satisfy constraints for '{}': "
                 "installation from path or url cannot be "
@@ -75,14 +75,12 @@ class SpecifierRequirement(Requirement):
         canonical_name = canonicalize_name(self._ireq.req.name)
         return format_name(canonical_name, self.extras)
 
-    def find_matches(self):
-        # type: () -> Sequence[Candidate]
+    def find_matches(self, constraints):
+        # type: (Sequence[SpecifierSet]) -> Sequence[Candidate]
         it = self._factory.iter_found_candidates(self._ireq, self.extras)
-        constraints = self._factory._constraints.get(self.name, [])
-        lit = [c for c in it if all(
+        return [c for c in it if all(
             s.contains(c.version, prereleases=True) for s in constraints
         )]
-        return lit
 
     def is_satisfied_by(self, candidate):
         # type: (Candidate) -> bool
@@ -116,8 +114,8 @@ class RequiresPythonRequirement(Requirement):
         # type: () -> str
         return self._candidate.name
 
-    def find_matches(self):
-        # type: () -> Sequence[Candidate]
+    def find_matches(self, constraints):
+        # type: (Sequence[SpecifierSet]) -> Sequence[Candidate]
         if self._candidate.version in self.specifier:
             return [self._candidate]
         return []

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

@@ -84,11 +84,9 @@ class Resolver(BaseResolver):
                     self.factory.make_requirement_from_install_req(req)
                 )
 
-        # TODO: Refactor this, it's just for proof of concept
-        self.factory._constraints = constraints
-
         provider = PipProvider(
             factory=self.factory,
+            constraints=constraints,
             ignore_dependencies=self.ignore_dependencies,
         )
         reporter = BaseReporter()

tests/unit/resolution_resolvelib/conftest.py

@@ -64,5 +64,6 @@ def factory(finder, preparer):
 def provider(factory):
     yield PipProvider(
         factory=factory,
+        constraints={},
         ignore_dependencies=False,
     )

tests/unit/resolution_resolvelib/test_requirement.py

@@ -58,14 +58,14 @@ def test_new_resolver_correct_number_of_matches(test_cases, factory):
     """Requirements should return the correct number of candidates"""
     for spec, name, matches in test_cases:
         req = factory.make_requirement_from_spec(spec, comes_from=None)
-        assert len(req.find_matches()) == matches
+        assert len(req.find_matches([])) == matches
 
 
 def test_new_resolver_candidates_match_requirement(test_cases, factory):
     """Candidates returned from find_matches should satisfy the requirement"""
     for spec, name, matches in test_cases:
         req = factory.make_requirement_from_spec(spec, comes_from=None)
-        for c in req.find_matches():
+        for c in req.find_matches([]):
             assert isinstance(c, Candidate)
             assert req.is_satisfied_by(c)