Refactor launchy option

lib/guard/rubocop/runner.rb

@@ -128,10 +128,10 @@ def pluralize(number, thing, options = {})
       end
 
       def open_launchy
-        return unless @options[:launchy]
+        return unless (output_path = @options[:launchy])
+        return unless File.exist?(output_path)
         require 'launchy'
-        pn = Pathname.new(@options[:launchy])
-        ::Launchy.open(@options[:launchy]) if pn.exist?
+        ::Launchy.open(output_path)
       end
     end
   end

spec/guard/rubocop/runner_spec.rb

@@ -92,8 +92,7 @@
       let(:options) { { launchy: 'launchy_path' } }
 
       before do
-        allow(Pathname).to receive(:new)
-          .with('launchy_path') { double(exist?: true) }
+        allow(File).to receive(:exist?).with('launchy_path').and_return(true)
       end
 
       it 'opens Launchy' do