Upgrade resolvelib to 1.2.0

news/resolvelib.vendor.rst

@@ -0,0 +1 @@
+Upgrade resolvelib to 1.2.0

src/pip/_vendor/resolvelib/__init__.py

@@ -1,17 +1,17 @@
 __all__ = [
-    "__version__",
     "AbstractProvider",
     "AbstractResolver",
     "BaseReporter",
     "InconsistentCandidate",
-    "Resolver",
     "RequirementsConflicted",
     "ResolutionError",
     "ResolutionImpossible",
     "ResolutionTooDeep",
+    "Resolver",
+    "__version__",
 ]
 
-__version__ = "1.1.0"
+__version__ = "1.2.0"
 
 
 from .providers import AbstractProvider

src/pip/_vendor/resolvelib/reporters.py

@@ -9,7 +9,7 @@
 
 
 class BaseReporter(Generic[RT, CT, KT]):
-    """Delegate class to provider progress reporting for the resolver."""
+    """Delegate class to provide progress reporting for the resolver."""
 
     def starting(self) -> None:
         """Called before the resolution actually starts."""

src/pip/_vendor/resolvelib/resolvers/__init__.py

@@ -13,15 +13,15 @@
 
 __all__ = [
     "AbstractResolver",
+    "Criterion",
     "InconsistentCandidate",
-    "Resolver",
-    "Resolution",
+    "RequirementInformation",
     "RequirementsConflicted",
+    "Resolution",
     "ResolutionError",
     "ResolutionImpossible",
     "ResolutionTooDeep",
-    "RequirementInformation",
+    "Resolver",
     "ResolverException",
     "Result",
-    "Criterion",
 ]

src/pip/_vendor/resolvelib/resolvers/resolution.py

@@ -3,7 +3,7 @@
 import collections
 import itertools
 import operator
-from typing import TYPE_CHECKING, Collection, Generic, Iterable, Mapping
+from typing import TYPE_CHECKING, Generic
 
 from ..structs import (
     CT,
@@ -27,9 +27,13 @@
 )
 
 if TYPE_CHECKING:
+    from collections.abc import Collection, Iterable, Mapping
+
     from ..providers import AbstractProvider, Preference
     from ..reporters import BaseReporter
 
+_OPTIMISTIC_BACKJUMPING_RATIO: float = 0.1
+
 
 def _build_result(state: State[RT, CT, KT]) -> Result[RT, CT, KT]:
     mapping = state.mapping
@@ -77,6 +81,11 @@ def __init__(
         self._r = reporter
         self._states: list[State[RT, CT, KT]] = []
 
+        # Optimistic backjumping variables
+        self._optimistic_backjumping_ratio = _OPTIMISTIC_BACKJUMPING_RATIO
+        self._save_states: list[State[RT, CT, KT]] | None = None
+        self._optimistic_start_round: int | None = None
+
     @property
     def state(self) -> State[RT, CT, KT]:
         try:
@@ -274,6 +283,25 @@ def _patch_criteria(
             )
         return True
 
+    def _save_state(self) -> None:
+        """Save states for potential rollback if optimistic backjumping fails."""
+        if self._save_states is None:
+            self._save_states = [
+                State(
+                    mapping=s.mapping.copy(),
+                    criteria=s.criteria.copy(),
+                    backtrack_causes=s.backtrack_causes[:],
+                )
+                for s in self._states
+            ]
+
+    def _rollback_states(self) -> None:
+        """Rollback states and disable optimistic backjumping."""
+        self._optimistic_backjumping_ratio = 0.0
+        if self._save_states:
+            self._states = self._save_states
+            self._save_states = None
+
     def _backjump(self, causes: list[RequirementInformation[RT, CT]]) -> bool:
         """Perform backjumping.
 
@@ -324,13 +352,26 @@ def _backjump(self, causes: list[RequirementInformation[RT, CT]]) -> bool:
                 except (IndexError, KeyError):
                     raise ResolutionImpossible(causes) from None
 
-                # Only backjump if the current broken state is
-                # an incompatible dependency
-                if name not in incompatible_deps:
+                if (
+                    not self._optimistic_backjumping_ratio
+                    and name not in incompatible_deps
+                ):
+                    # For safe backjumping only backjump if the current dependency
+                    # is not the same as the incompatible dependency
                     break
 
+                # On the first time a non-safe backjump is done the state
+                # is saved so we can restore it later if the resolution fails
+                if (
+                    self._optimistic_backjumping_ratio
+                    and self._save_states is None
+                    and name not in incompatible_deps
+                ):
+                    self._save_state()
+
                 # If the current dependencies and the incompatible dependencies
-                # are overlapping then we have found a cause of the incompatibility
+                # are overlapping then we have likely found a cause of the
+                # incompatibility
                 current_dependencies = {
                     self._p.identify(d) for d in self._p.get_dependencies(candidate)
                 }
@@ -394,9 +435,32 @@ def resolve(self, requirements: Iterable[RT], max_rounds: int) -> State[RT, CT,
         # pinning the virtual "root" package in the graph.
         self._push_new_state()
 
+        # Variables for optimistic backjumping
+        optimistic_rounds_cutoff: int | None = None
+        optimistic_backjumping_start_round: int | None = None
+
         for round_index in range(max_rounds):
             self._r.starting_round(index=round_index)
 
+            # Handle if optimistic backjumping has been running for too long
+            if self._optimistic_backjumping_ratio and self._save_states is not None:
+                if optimistic_backjumping_start_round is None:
+                    optimistic_backjumping_start_round = round_index
+                    optimistic_rounds_cutoff = int(
+                        (max_rounds - round_index) * self._optimistic_backjumping_ratio
+                    )
+
+                    if optimistic_rounds_cutoff <= 0:
+                        self._rollback_states()
+                        continue
+                elif optimistic_rounds_cutoff is not None:
+                    if (
+                        round_index - optimistic_backjumping_start_round
+                        >= optimistic_rounds_cutoff
+                    ):
+                        self._rollback_states()
+                        continue
+
             unsatisfied_names = [
                 key
                 for key, criterion in self.state.criteria.items()
@@ -448,12 +512,29 @@ def resolve(self, requirements: Iterable[RT], max_rounds: int) -> State[RT, CT,
                 # Backjump if pinning fails. The backjump process puts us in
                 # an unpinned state, so we can work on it in the next round.
                 self._r.resolving_conflicts(causes=causes)
-                success = self._backjump(causes)
-                self.state.backtrack_causes[:] = causes
 
-                # Dead ends everywhere. Give up.
-                if not success:
-                    raise ResolutionImpossible(self.state.backtrack_causes)
+                try:
+                    success = self._backjump(causes)
+                except ResolutionImpossible:
+                    if self._optimistic_backjumping_ratio and self._save_states:
+                        failed_optimistic_backjumping = True
+                    else:
+                        raise
+                else:
+                    failed_optimistic_backjumping = bool(
+                        not success
+                        and self._optimistic_backjumping_ratio
+                        and self._save_states
+                    )
+
+                if failed_optimistic_backjumping and self._save_states:
+                    self._rollback_states()
+                else:
+                    self.state.backtrack_causes[:] = causes
+
+                    # Dead ends everywhere. Give up.
+                    if not success:
+                        raise ResolutionImpossible(self.state.backtrack_causes)
             else:
                 # discard as information sources any invalidated names
                 # (unsatisfied names that were previously satisfied)

src/pip/_vendor/vendor.txt

@@ -12,7 +12,7 @@ requests==2.32.4
 rich==14.0.0
     pygments==2.19.2
     typing_extensions==4.14.0
-resolvelib==1.1.0
+resolvelib==1.2.0
 setuptools==70.3.0
 tomli==2.2.1
 tomli-w==1.2.0