--- a/mercurial/scmutil.py	Wed Mar 06 12:07:31 2024 +0100
+++ b/mercurial/scmutil.py	Wed Mar 06 11:39:44 2024 +0100
@@ -385,6 +385,37 @@
     return result
 
 
+def filtered_and_obsolete_hash(repo, maxrev):
+    """build hashs of filtered and obsolete revisions in the current repoview.
+
+    Multiple caches perform up-to-date validation by checking that the
+    tiprev and tipnode stored in the cache file match the current repository.
+    However, this is not sufficient for validating repoviews because the set
+    of revisions in the view may change without the repository tiprev and
+    tipnode changing.
+
+    This function hashes all the revs filtered from the view up to maxrev and
+    returns that SHA-1 digest. The obsolete revisions hashed are only the
+    non-filtered one.
+    """
+    cl = repo.changelog
+    obs_set = obsolete.getrevs(repo, b'obsolete')
+    key = (maxrev, hash(cl.filteredrevs), hash(obs_set))
+
+    result = cl._filteredrevs_hashcache.get(key)
+    if result is None:
+        filtered_hash = None
+        obs_hash = None
+        filtered_revs, obs_revs = _filtered_and_obs_revs(repo, maxrev)
+        if filtered_revs:
+            filtered_hash = _hash_revs(filtered_revs)
+        if obs_revs:
+            obs_hash = _hash_revs(obs_revs)
+        result = (filtered_hash, obs_hash)
+        cl._filteredrevs_hashcache[key] = result
+    return result
+
+
 def _filtered_and_obs_revs(repo, max_rev):
     """return the set of filtered and non-filtered obsolete revision"""
     cl = repo.changelog