Refactor list-attributes-on-file dev script to Ruby

Author: danielbayley

cmd/brew-list-url-attributes-on-file

@@ -0,0 +1,44 @@
+# typed: strict
+# frozen_string_literal: true
+
+require "abstract_command"
+require "open3"
+
+module Homebrew
+  module Cmd
+    class ListUrlAttributesOnFileCmd < AbstractCommand
+      cmd_args do
+        usage_banner <<~EOS
+          `list-url-attributes-on-file` <file>
+
+          Given a downloaded file, extract possible sources from macOS extended
+          attributes, which may be useful in a Cask url stanza.
+
+          Currently the only attribute examined is
+
+              com.apple.metadata:kMDItemWhereFroms
+
+          This attribute will typically be set if the file was downloaded via a
+          browser, but not if the file was downloaded by a CLI utility such as
+          curl.
+
+          See CONTRIBUTING.md for more information.
+        EOS
+
+        named_args :file, max: 1
+
+        hide_from_man_page!
+      end
+
+      sig { override.returns(T.any(T.nilable(String), T::Array[String])) }
+      def run
+        attribute = "com.apple.metadata:kMDItemWhereFroms"
+        xattr, _, status = Open3.capture3("/usr/bin/xattr -p #{attribute} #{args.named.first}")
+
+        exit status.exitstatus.to_i unless status.success?
+
+        puts Plist.parse_xml(xattr, marshal: false) || xattr
+      end
+    end
+  end
+end