# HG changeset patch
# User Pierre-Yves David <pierre-yves.david@octobus.net>
# Date 1622729523 -7200
# Node ID 298d4400ea687e5fbbfa4303d7d6205ef4440d62
# Parent  ab5fd39cb4022f696326838e1e19a218b2894e2d
index: use an explicit constant for INDEX_HEADER format and use it for docket

This avoid leaking python-3.6 compatibility details too much.

Differential Revision: https://phab.mercurial-scm.org/D10831

diff -r ab5fd39cb402 -r 298d4400ea68 mercurial/revlogutils/constants.py
--- a/mercurial/revlogutils/constants.py	Tue Jun 01 09:18:27 2021 +0200
+++ b/mercurial/revlogutils/constants.py	Thu Jun 03 16:12:03 2021 +0200
@@ -29,7 +29,9 @@
 
 ### main revlog header
 
-INDEX_HEADER = struct.Struct(b">I")
+# We cannot rely on  Struct.format is inconsistent for python <=3.6 versus above
+INDEX_HEADER_FMT = b">I"
+INDEX_HEADER = struct.Struct(INDEX_HEADER_FMT)
 
 ## revlog version
 REVLOGV0 = 0
diff -r ab5fd39cb402 -r 298d4400ea68 mercurial/revlogutils/docket.py
--- a/mercurial/revlogutils/docket.py	Tue Jun 01 09:18:27 2021 +0200
+++ b/mercurial/revlogutils/docket.py	Thu Jun 03 16:12:03 2021 +0200
@@ -95,9 +95,7 @@
 # * 8 bytes: size of data
 # * 8 bytes: pending size of data
 # * 1 bytes: default compression header
-S_HEADER = struct.Struct(
-    pycompat.sysstr(constants.INDEX_HEADER.format) + 'BBLLLLc'
-)
+S_HEADER = struct.Struct(constants.INDEX_HEADER_FMT + b'BBLLLLc')
 
 
 class RevlogDocket(object):