--- a/mercurial/interfaces/repository.py	Sat Aug 08 10:06:32 2020 -0700
+++ b/mercurial/interfaces/repository.py	Fri Aug 07 18:01:48 2020 +0530
@@ -18,6 +18,10 @@
 # Enables sparse working directory usage
 SPARSE_REQUIREMENT = b'exp-sparse'
 
+# Enables the internal phase which is used to hide changesets instead
+# of stripping them
+INTERNAL_PHASE_REQUIREMENT = b'internal-phase'
+
 # Local repository feature string.
 
 # Revlogs are being used for file storage.