nix-universal-prefetch: init at 0.4.0

This package was deleted in 578d7e7. This broke the Electron
update script.

This fixes the Electron update script.

Fixes NixOS#321490

pkgs/by-name/ni/nix-universal-prefetch/package.nix

@@ -0,0 +1,34 @@
+{ lib, stdenv
+, fetchFromGitHub
+, ruby
+}:
+
+# No gems used, so mkDerivation is fine.
+stdenv.mkDerivation rec {
+  pname = "nix-universal-prefetch";
+  version = "0.4.0";
+
+  src = fetchFromGitHub {
+    owner = "Marcus-Arcadius";
+    repo = "nix-universal-prefetch";
+    rev = "v${version}";
+    hash = "sha256-HGn4qHWqpUwlS3yQrD3j5oH0yOlphsoSPD2vkyyRv+0=";
+  };
+
+  installPhase = ''
+    mkdir -pv $out/bin
+    cp nix-universal-prefetch $out/bin/nix-universal-prefetch
+    substituteInPlace "$out/bin/nix-universal-prefetch" \
+      --replace "/usr/bin/env nix-shell" "${ruby}/bin/ruby"
+  '';
+
+  meta = with lib; {
+    description = "Uses nixpkgs fetchers to figure out hashes";
+    homepage = "https://github.com/squalus/nix-universal-prefetch";
+    license = licenses.mit;
+    maintainers = with maintainers; [ squalus ];
+    platforms = platforms.linux ++ platforms.darwin;
+    mainProgram = "nix-universal-prefetch";
+  };
+}
+

pkgs/top-level/aliases.nix

@@ -955,7 +955,6 @@ mapAliases ({
   );
   nix-review = throw "'nix-review' has been renamed to/replaced by 'nixpkgs-review'"; # Converted to throw 2023-09-10
   nix-template-rpm = throw "'nix-template-rpm' has been removed as it is broken and unmaintained"; # Added 2023-11-20
-  nix-universal-prefetch = throw "The nix-universal-prefetch package was dropped since it was unmaintained."; # Added 2024-06-21
   nixFlakes = nixVersions.stable; # Added 2021-05-21
   nixStable = nixVersions.stable; # Added 2022-01-24
   nixUnstable = throw "nixUnstable has been removed. For bleeding edge (Nix master, roughly weekly updated) use nixVersions.git, otherwise use nixVersions.latest."; # Converted to throw 2024-04-22