cask: compact the code

Library/Homebrew/cask/lib/hbc/artifact/pkg.rb

@@ -54,24 +54,23 @@ module Hbc
         ]
         args << "-verboseR" if Hbc.verbose
         args << "-allowUntrusted" if pkg_install_opts :allow_untrusted
-        with_choices_file pkg_install_opts(:choices) do |choices_path|
+        with_choices_file do |choices_path|
           args << "-applyChoiceChangesXML" << choices_path if choices_path
           @command.run!("/usr/sbin/installer", sudo: true, args: args, print_stdout: true)
         end
       end
 
-      def with_choices_file(choices)
-        unless choices
-          yield nil
-          return
-        end
+      def with_choices_file
+        return yield nil unless pkg_install_opts(:choices)
 
-        begin
-          file = Tempfile.new(["choices", ".xml"])
-          file.write Plist::Emit.dump(choices)
-          yield file.path
-        ensure
-          file.close(true)
+        Tempfile.open(["choices", ".xml"]) do |file|
+          begin
+            file.write Plist::Emit.dump(pkg_install_opts(:choices))
+            file.close
+            yield file.path
+          ensure
+            file.unlink
+          end
         end
       end
     end

Library/Homebrew/cask/test/cask/artifact/pkg_test.rb

@@ -60,8 +60,9 @@ describe Hbc::Artifact::Pkg do
         </plist>
       EOS
       file.stubs path: Pathname.new("/tmp/choices.xml")
-      file.expects(:close).with true
-      Tempfile.expects(:new).returns file
+      file.expects(:close)
+      file.expects(:unlink)
+      Tempfile.expects(:open).yields file
 
       Hbc::FakeSystemCommand.expects_command(["/usr/bin/sudo", "-E", "--", "/usr/sbin/installer", "-pkg", @cask.staged_path.join("MyFancyPkg", "Fancy.pkg"), "-target", "/", "-applyChoiceChangesXML", @cask.staged_path.join("/tmp/choices.xml")])