From 350a469f731122997b3a54b876f9b3a59fa0b63d Mon Sep 17 00:00:00 2001
From: Wolfgang Walther <walther@technowledgy.de>
Date: Thu, 30 Oct 2025 08:42:11 +0100
Subject: [PATCH] ci/eval/diff: avoid copying paths.json

Currently the `diff-<system>` artifacts are 6-7 MB in size - and almost
all of that is the `paths.json` file, which is only used to generate the
diff itself. This had been stored in the artifact previously for
debugging purposes. Ever since we moved to Cachix this is not required
anymore, since it's possible to run the same eval locally and thus fetch
the `eval.singleSystem` result, including `paths.json`, from Cachix.

This will be even more helpful when the next step adds `meta.json` -
which is magnitudes bigger than `paths.json`.
---
 ci/eval/diff.nix | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/ci/eval/diff.nix b/ci/eval/diff.nix
index 692e2ec60194..0f757ce3dd12 100644
--- a/ci/eval/diff.nix
+++ b/ci/eval/diff.nix
@@ -80,7 +80,10 @@ in
 runCommand "diff" { } ''
   mkdir -p $out/${evalSystem}
 
-  cp -r ${before} $out/before
-  cp -r ${after} $out/after
+  cp -r --no-preserve=mode ${before} $out/before
+  cp -r --no-preserve=mode ${after} $out/after
+  # JSON files will be processed above explicitly, so avoid copying over
+  # the source files to keep the artifacts smaller.
+  find $out/before $out/after -iname '*.json' -delete
   cp ${diffJson} $out/${evalSystem}/diff.json
 ''