stop mutating ARGV

railties/lib/rails/commands/application.rb

@@ -13,5 +13,5 @@ def self.exit_on_failure?
   end
 end
 
-Rails::Generators::ARGVScrubber.new(ARGV).prepare!
-Rails::Generators::AppGenerator.start
+args = Rails::Generators::ARGVScrubber.new(ARGV).prepare!
+Rails::Generators::AppGenerator.start args

railties/lib/rails/generators/rails/app/app_generator.rb

@@ -315,7 +315,7 @@ class ARGVScrubber # :nodoc
       attr_reader :argv
 
       def initialize(argv = ARGV)
-        @argv = argv
+        @argv = argv.dup
       end
 
       def prepare!