changelog-v2: add a configuration to disable rank computation We encountered a graph where rank computation was pathologically slow. We add an option to disable this computation while this is getting fixed. Disabling the rank computation should allow for testing other changelog-v2 features undisturbed (like changeset-based copy tracing). I am purposely not adding a test for the new non-default code path, as this is a temporary work around of an experimental feature.

--- a/mercurial/configitems.py	Mon Nov 21 15:04:19 2022 +0100
+++ b/mercurial/configitems.py	Tue Nov 22 12:44:22 2022 +0100
@@ -923,6 +923,13 @@
     b'changegroup4',
     default=False,
 )
+
+# might remove rank configuration once the computation has no impact
+coreconfigitem(
+    b'experimental',
+    b'changelog-v2.compute-rank',
+    default=True,
+)
 coreconfigitem(
     b'experimental',
     b'cleanup-as-archived',