mercurial/metadata.py

--- a/mercurial/metadata.py	Thu Feb 18 18:18:35 2021 +0100
+++ b/mercurial/metadata.py	Fri Feb 19 10:53:27 2021 +0100
@@ -18,6 +18,7 @@
 from . import (
     error,
     pycompat,
+    requirements as requirementsmod,
     util,
 )
 
@@ -804,6 +805,21 @@
     return encode_files_sidedata(files), files.has_copies_info
 
 
+def copies_sidedata_computer(repo, revlog, rev, existing_sidedata):
+    return _getsidedata(repo, rev)[0]
+
+
+def set_sidedata_spec_for_repo(repo):
+    if requirementsmod.COPIESSDC_REQUIREMENT in repo.requirements:
+        repo.register_wanted_sidedata(sidedatamod.SD_FILES)
+        repo.register_sidedata_computer(
+            b"changelog",
+            sidedatamod.SD_FILES,
+            (sidedatamod.SD_FILES,),
+            copies_sidedata_computer,
+        )
+
+
 def getsidedataadder(srcrepo, destrepo):
     use_w = srcrepo.ui.configbool(b'experimental', b'worker.repository-upgrade')
     if pycompat.iswindows or not use_w: