--- a/mercurial/revlogutils/constants.py	Wed Dec 15 15:28:30 2021 +0100
+++ b/mercurial/revlogutils/constants.py	Tue Dec 14 19:24:24 2021 +0100
@@ -184,6 +184,15 @@
 #  27 bytes: Padding to align to 96 bytes (see RevlogV2Plan wiki page)
 INDEX_ENTRY_CL_V2 = struct.Struct(b">Qiiii20s12xQiB27x")
 assert INDEX_ENTRY_CL_V2.size == 32 * 3, INDEX_ENTRY_V2.size
+INDEX_ENTRY_V2_IDX_OFFSET = 0
+INDEX_ENTRY_V2_IDX_COMPRESSED_LENGTH = 1
+INDEX_ENTRY_V2_IDX_UNCOMPRESSED_LENGTH = 2
+INDEX_ENTRY_V2_IDX_PARENT_1 = 3
+INDEX_ENTRY_V2_IDX_PARENT_2 = 4
+INDEX_ENTRY_V2_IDX_NODEID = 5
+INDEX_ENTRY_V2_IDX_SIDEDATA_OFFSET = 6
+INDEX_ENTRY_V2_IDX_SIDEDATA_COMPRESSED_LENGTH = 7
+INDEX_ENTRY_V2_IDX_COMPRESSION_MODE = 8
 
 # revlog index flags