# HG changeset patch
# User Rapha?l Gom?s <rgomes@octobus.net>
# Date 1740164171 18000
# Node ID 155e1e8dc055ccb82d291fdb53fac8e8dcbf010a
# Parent  33e06272ff1a225ba5e9fb1bdb8a12c3d9f78a64
rust-nodemap: don't compute the error string unless needed

This is... really dumb and costs a ton of performance in a hot loop. It was
75% of a profile for a tip to null p1 node traversal in pure Rust.

I'm at fault, done in 652149ed64f08ee73e8fd2f76aa480ea8820fe08.

I thought clippy had a lint for this, but apparently not?

diff -r 33e06272ff1a -r 155e1e8dc055 rust/hg-core/src/revlog/mod.rs
--- a/rust/hg-core/src/revlog/mod.rs	Thu Feb 20 11:44:44 2025 +0100
+++ b/rust/hg-core/src/revlog/mod.rs	Fri Feb 21 13:56:11 2025 -0500
@@ -374,7 +374,9 @@
             nodemap
                 .find_bin(self.index(), node)
                 .map_err(|err| (err, format!("{:x}", node)))?
-                .ok_or(RevlogError::InvalidRevision(format!("{:x}", node)))
+                .ok_or_else(|| {
+                    RevlogError::InvalidRevision(format!("{:x}", node))
+                })
         } else {
             self.index().rev_from_node_no_persistent_nodemap(node)
         }