# HG changeset patch
# User Antoine cezar<acezar@chwitlabs.fr>
# Date 2020-09-28 11:51:16
# Node ID f38adf8b0711bb0ab7fdc0a9fce876549312818e
# Parent  11f3c3f408fdc213a33c4d01a0556318e99f9f16

hg-core: Explain offset override of first revision

(D8958#inline-14992 followup)

Differential Revision: https://phab.mercurial-scm.org/D9095

diff --git a/rust/hg-core/src/revlog/index.rs b/rust/hg-core/src/revlog/index.rs
--- a/rust/hg-core/src/revlog/index.rs
+++ b/rust/hg-core/src/revlog/index.rs
@@ -98,7 +98,8 @@ impl<'a> Index<'a> {
         let end = start + INDEX_ENTRY_SIZE;
         let bytes = &self.bytes[start..end];
 
-        // See IndexEntry for an explanation of this override.
+        // Override the offset of the first revision as its bytes are used
+        // for the index's metadata (saving space because it is always 0)
         let offset_override = match rev {
             0 => Some(0),
             _ => None,