unityhub: add update script

pkgs/development/tools/unityhub/default.nix

@@ -119,6 +119,8 @@ stdenv.mkDerivation rec {
     runHook postInstall
   '';
 
+  passthru.updateScript = ./update.sh;
+
   meta = with lib; {
     description = "Official Unity3D app to download and manage Unity Projects and installations";
     homepage = "https://unity3d.com/";

pkgs/development/tools/unityhub/update.sh

@@ -0,0 +1,13 @@
+#!/usr/bin/env nix-shell
+#!nix-shell -i bash -p curl common-updater-scripts
+# set -euo pipefail
+
+new_version="$(curl https://hub-dist.unity3d.com/artifactory/hub-debian-prod-local/dists/stable/main/binary-amd64/Packages --silent | sed -nE "s/^Version: ([0-9]+\.[0-9]+\.[0-9]+)$/\1/p" | sort -V | tail -n 1)"
+old_version="$(sed -nE 's/^\s*version = "([0-9]+\.[0-9]+\.[0-9]+)";$/\1/p' ./default.nix)"
+
+if [[ "$new_version" == "$old_version" ]]; then
+    echo "Up to date"
+    exit 0
+fi
+
+update-source-version unityhub "$new_version"