From dd151c9f1a5b761fe2f5f19180e059792977b47e Mon Sep 17 00:00:00 2001
From: Giulio De Pasquale <git@depasquale.giugl.io>
Date: Tue, 22 Apr 2025 11:14:58 +0100
Subject: [PATCH] fix(update_cached_hashes.sh): update script to correctly
 parse and handle hash changes

---
 update_cached_hashes.sh | 16 ++++++++++++----
 1 file changed, 12 insertions(+), 4 deletions(-)

diff --git a/update_cached_hashes.sh b/update_cached_hashes.sh
index f468c5d..fe73e29 100755
--- a/update_cached_hashes.sh
+++ b/update_cached_hashes.sh
@@ -5,10 +5,18 @@
 # (so we don't have to rebuild EVERYTHING)
 RELEASE=24.11
 
+set -e
+
 new=$(curl -sL "https://monitoring.nixos.org/prometheus/api/v1/query?query=channel_revision" | jq -r ".data.result[] | select(.metric.channel==\"nixos-${RELEASE}\") | .metric.revision")
-old=$(jq -r ".nodes.nixpkgs.locked.rev" flake.lock)
+old=$(jq -r '.nodes as $nodes | .nodes.root.inputs.nixpkgs as $tgt_nixpkgs | $nodes | to_entries[] | select(.key == $tgt_nixpkgs) | .value.locked.rev' flake.lock)
 
-echo "Old hash: ${old}"
-echo "New hash: ${new}"
+if [ "${old}" != "${new}" ]; then
+  echo "Old hash: ${old}"
+  echo "New hash: ${new}"
 
-sed -i s/"${old}"/"${new}"/ flake.nix
+  sed -i s/"${old}"/"${new}"/ flake.nix
+
+  exit
+fi
+
+echo "No updates available."