erlang: add updateScript and update versions (#118831)

Co-authored-by: Sandro <sandro.jaeckel@gmail.com>

pkgs/development/interpreters/erlang/generic-builder.nix

@@ -5,6 +5,8 @@
 , libGL ? null, libGLU ? null, wxGTK ? null, wxmac ? null, xorg ? null
 , parallelBuild ? false
 , systemd, wxSupport ? true
+# updateScript deps
+, writeScript, common-updater-scripts, coreutils, git
 }:
 { baseName ? "erlang"
 , version
@@ -103,6 +105,24 @@ in stdenv.mkDerivation ({
 
   setupHook = ./setup-hook.sh;
 
+  passthru = {
+    updateScript =
+      let major = builtins.head (builtins.splitVersion version);
+      in writeScript "update.sh" ''
+      #!${stdenv.shell}
+      set -ox errexit
+      PATH=${lib.makeBinPath [ common-updater-scripts coreutils git gnused ]}
+      latest=$(list-git-tags https://github.com/erlang/otp.git | sed -n 's/^OTP-${major}/${major}/p' | sort -V | tail -1)
+      if [ "$latest" != "${version}" ]; then
+        nixpkgs="$(git rev-parse --show-toplevel)"
+        nix_file="$nixpkgs/pkgs/development/interpreters/erlang/R${major}.nix"
+        update-source-version ${baseName}R${major} "$latest" --version-key=version --print-changes --file="$nix_file"
+      else
+        echo "${baseName}R${major} is already up-to-date"
+      fi
+    '';
+  };
+
   meta = with lib; ({
     homepage = "https://www.erlang.org/";
     downloadPage = "https://www.erlang.org/download.html";