Do not fetch VCS deps when reference didn't change

src/poetry/mixology/version_solver.py

@@ -448,7 +448,7 @@ def _get_min(dependency: Dependency) -> tuple[bool, int]:
         else:
             package = locked
 
-        package = self._provider.complete_package(package)
+        package = self._provider.complete_package(package, get_locked=self._get_locked)
 
         conflict = False
         for incompatibility in self._provider.incompatibilities_for(package):

src/poetry/puzzle/provider.py

@@ -40,6 +40,7 @@
     from collections.abc import Callable
     from collections.abc import Iterable
     from collections.abc import Iterator
+    from typing import Protocol
 
     from cleo.io.io import IO
     from poetry.core.packages.dependency import Dependency
@@ -508,7 +509,10 @@ def incompatibilities_for(
         ]
 
     def complete_package(
-        self, dependency_package: DependencyPackage
+        self,
+        dependency_package: DependencyPackage,
+        *,
+        get_locked: GetLocked | None = None,
     ) -> DependencyPackage:
         package = dependency_package.package
         dependency = dependency_package.dependency
@@ -553,6 +557,13 @@ def complete_package(
             # Retrieving constraints for deferred dependencies
             for r in requires:
                 if r.is_direct_origin():
+                    if get_locked is not None:
+                        locked = get_locked(r, allow_similar=False)
+                        # If lock file contains exactly the same URL and reference
+                        # (commit hash) of dependency as is requested,
+                        # do not analyze it again: nothing could have changed.
+                        if locked is not None and locked.package.is_same_package_as(r):
+                            continue
                     self.search_for_direct_origin_dependency(r)
 
         optional_dependencies = []
@@ -957,3 +968,12 @@ def _merge_dependencies_by_marker(
                     )
                     deps.append(_deps[0].with_constraint(new_constraint))
         return deps
+
+
+if TYPE_CHECKING:
+
+    class GetLocked(Protocol):
+        def __call__(
+            self, dependency: Dependency, *, allow_similar: bool = False
+        ) -> DependencyPackage | None:
+            ...