stream-clone: allow to change persistent-nodemap format during stream clone Persistent nodemap affect the store format. However it is fairly isolated and fast to generate locally. So not making it a fixed part of the stream clone is useful. This allow clients without persistent-nodemap support (default for client without Rust enabled, or simply older client). So it make it possible to enable persistent nodemap on client, where it can provide a massive boost. without too much consequence. To do so, we stop using it in the advertisement requirements for streaming and let the client add/remove the necessary file depending of its configuration. We still send the files as it seems like a small save to not regenerate them. In addition, the way we match them will overlap with the changelog-v2/revlog-v2 so we can't simply skip the associated patterns. Differential Revision: https://phab.mercurial-scm.org/D12096

--- a/mercurial/revlogutils/nodemap.py	Thu Jan 27 15:22:09 2022 +0100
+++ b/mercurial/revlogutils/nodemap.py	Thu Jan 27 22:24:11 2022 +0100
@@ -16,6 +16,7 @@
 
 from .. import (
     error,
+    requirements,
     util,
 )
 from . import docket as docket_mod
@@ -34,6 +35,19 @@
     pass
 
 
+def post_stream_cleanup(repo):
+    """The stream clone might needs to remove some file if persisten nodemap
+    was dropped while stream cloning
+    """
+    if requirements.REVLOGV1_REQUIREMENT not in repo.requirements:
+        return
+    if requirements.NODEMAP_REQUIREMENT in repo.requirements:
+        return
+    unfi = repo.unfiltered()
+    delete_nodemap(None, unfi, unfi.changelog)
+    delete_nodemap(None, repo, unfi.manifestlog._rootstore._revlog)
+
+
 def persisted_data(revlog):
     """read the nodemap for a revlog from disk"""
     if revlog._nodemap_file is None: