diff --git a/Library/Homebrew/formula.rb b/Library/Homebrew/formula.rb
index 162d93fbac..e8220d1fa0 100644
--- a/Library/Homebrew/formula.rb
+++ b/Library/Homebrew/formula.rb
@@ -1704,13 +1704,8 @@ class Formula
         "#{shell_parameter_format}#{shell}"
       end
 
-      popen_read_args = %w[]
-      popen_read_args << commands
-      popen_read_args << shell_parameter
-      popen_read_args.flatten!
-
       script_path.dirname.mkpath
-      script_path.write Utils.safe_popen_read({ "SHELL" => shell.to_s }, *popen_read_args)
+      script_path.write Utils.safe_popen_read({ "SHELL" => shell.to_s }, *commands, shell_parameter)
     end
   end