From 76d059bac23d8ee5bb5cc624cd5a9206092ae8ab Mon Sep 17 00:00:00 2001
From: Matt Sturgeon <matt@sturgeon.me.uk>
Date: Mon, 7 Jul 2025 17:00:48 +0100
Subject: [PATCH] ci/version-info: create temp files in a temp directory

Avoid polluting the repo with temporary `channels.{nix,json,toml}`
files. Write them to a temporary working directory instead.

(cherry picked from commit bc997a240953bda9fa526e8a3d6f798a6072308a)
---
 update-scripts/version-info/default.nix | 31 +++++++++++++++----------
 1 file changed, 19 insertions(+), 12 deletions(-)

diff --git a/update-scripts/version-info/default.nix b/update-scripts/version-info/default.nix
index e11c0e4c..c746b1eb 100644
--- a/update-scripts/version-info/default.nix
+++ b/update-scripts/version-info/default.nix
@@ -20,24 +20,31 @@ writeShellApplication {
   };
 
   text = ''
-    # Download channel info from NixOS/infra
-    curl ${channelsURL} | nix eval --file - --json > channels.json
-
-    # Use channels.nix to build channels.toml
-    nix build --impure \
-      --file ${./supported-versions.nix} \
-      --argstr system ${stdenv.hostPlatform.system} \
-      --arg-from-file channelsJSON channels.json \
-      --out-link channels.toml
-
+    work=$(mktemp -d)
     (
+      cd "$work"
+
+      # Download channel info from NixOS/infra
+      curl ${channelsURL} | nix eval --file - --json > channels.json
+
+      # Use channels.nix to build channels.toml
+      nix build --impure \
+        --file ${./supported-versions.nix} \
+        --argstr system ${stdenv.hostPlatform.system} \
+        --arg-from-file channelsJSON channels.json \
+        --out-link channels.toml
+    )
+
+    {
       echo "# DO NOT MODIFY!"
       echo "# This file was generated by ${
         lib.strings.removePrefix (toString ../.. + "/") (toString ./default.nix)
       }"
       cat ${mainInfo}
       echo
-      cat channels.toml
-    ) > version-info.toml
+      cat "$work/channels.toml"
+    } > version-info.toml
+
+    rm -rf "$work"
   '';
 }