uniffi-bindgen: add update script

pkgs/development/tools/uniffi-bindgen/default.nix

@@ -35,6 +35,8 @@ rustPlatform.buildRustPackage rec {
       --suffix PATH : ${lib.strings.makeBinPath [ rustfmt ktlint yapf rubocop ] }
   '';
 
+  passthru.updateScript = ./update.sh;
+
   meta = with lib; {
     description = "Toolkit for building cross-platform software components in Rust";
     homepage = "https://mozilla.github.io/uniffi-rs/";

pkgs/development/tools/uniffi-bindgen/update.sh

@@ -0,0 +1,35 @@
+#!/usr/bin/env nix-shell
+#! nix-shell -p nix cargo rsync nix-update
+#! nix-shell -i bash
+
+set -euo pipefail
+
+if [[ -z "${UPDATE_NIX_ATTR_PATH+x}" ]]; then
+    echo "Error: run the following command from nixpkgs root:" >&2
+    echo "  nix-shell maintainers/scripts/update.nix --argstr package uniffi-bindgen" >&2
+    exit 1
+fi
+
+targetLockfile="$(dirname "$0")/Cargo.lock"
+
+# Update version and hash
+nix-update "$UPDATE_NIX_ATTR_PATH"
+
+# Update lockfile through `cargo update`
+src=$(nix-build -A "${UPDATE_NIX_ATTR_PATH}.src" --no-out-link)
+
+tmp=$(mktemp -d)
+
+cleanup() {
+  echo "Removing $tmp" >&2
+  rm -rf "$tmp"
+}
+
+trap cleanup EXIT
+
+rsync -a --chmod=ugo=rwX "$src/" "$tmp"
+
+pushd "$tmp"
+cargo update
+cp "Cargo.lock" "$targetLockfile"
+popd