Issue with indentation in rails about treetop HOT 6 CLOSED

     Failure/Error: Treetop.load(Rails.root.join('app', 'grammars', 'document.treetop').to_s)

     ArgumentError:
       negative argument
     # /home/bonflintstone/.rvm/gems/ruby-2.3.0/gems/treetop-1.4.12/lib/treetop/ruby_extensions/string.rb:25:in `tabto'
     # /home/bonflintstone/.rvm/gems/ruby-2.3.0/gems/treetop-1.4.12/lib/treetop/compiler/ruby_builder.rb:17:in `<<'
     # /home/bonflintstone/.rvm/gems/ruby-2.3.0/gems/treetop-1.4.12/lib/treetop/compiler/node_classes/inline_module.rb:18:in `block in compile'
     # /home/bonflintstone/.rvm/gems/ruby-2.3.0/gems/treetop-1.4.12/lib/treetop/compiler/ruby_builder.rb:26:in `indented'
     # /home/bonflintstone/.rvm/gems/ruby-2.3.0/gems/treetop-1.4.12/lib/treetop/compiler/ruby_builder.rb:38:in `module_declaration'
     # /home/bonflintstone/.rvm/gems/ruby-2.3.0/gems/treetop-1.4.12/lib/treetop/compiler/node_classes/inline_module.rb:17:in `compile'
     # /home/bonflintstone/.rvm/gems/ruby-2.3.0/gems/treetop-1.4.12/lib/treetop/compiler/node_classes/parsing_rule.rb:12:in `block in compile_inline_module_declarations'
     # /home/bonflintstone/.rvm/gems/ruby-2.3.0/gems/treetop-1.4.12/lib/treetop/compiler/node_classes/parsing_rule.rb:11:in `each'
     # /home/bonflintstone/.rvm/gems/ruby-2.3.0/gems/treetop-1.4.12/lib/treetop/compiler/node_classes/parsing_rule.rb:11:in `each_with_index'
     # /home/bonflintstone/.rvm/gems/ruby-2.3.0/gems/treetop-1.4.12/lib/treetop/compiler/node_classes/parsing_rule.rb:11:in `compile_inline_module_declarations'
     # /home/bonflintstone/.rvm/gems/ruby-2.3.0/gems/treetop-1.4.12/lib/treetop/compiler/node_classes/parsing_rule.rb:6:in `compile'
     # /home/bonflintstone/.rvm/gems/ruby-2.3.0/gems/treetop-1.4.12/lib/treetop/compiler/node_classes/declaration_sequence.rb:14:in `block in compile'
     # /home/bonflintstone/.rvm/gems/ruby-2.3.0/gems/treetop-1.4.12/lib/treetop/compiler/node_classes/declaration_sequence.rb:13:in `each'
     # /home/bonflintstone/.rvm/gems/ruby-2.3.0/gems/treetop-1.4.12/lib/treetop/compiler/node_classes/declaration_sequence.rb:13:in `compile'
     # /home/bonflintstone/.rvm/gems/ruby-2.3.0/gems/treetop-1.4.12/lib/treetop/compiler/node_classes/grammar.rb:11:in `block in compile'
     # /home/bonflintstone/.rvm/gems/ruby-2.3.0/gems/treetop-1.4.12/lib/treetop/compiler/ruby_builder.rb:26:in `indented'
     # /home/bonflintstone/.rvm/gems/ruby-2.3.0/gems/treetop-1.4.12/lib/treetop/compiler/ruby_builder.rb:38:in `module_declaration'
     # /home/bonflintstone/.rvm/gems/ruby-2.3.0/gems/treetop-1.4.12/lib/treetop/compiler/node_classes/grammar.rb:7:in `compile'
     # /home/bonflintstone/.rvm/gems/ruby-2.3.0/gems/treetop-1.4.12/lib/treetop/compiler/metagrammar.rb:39:in `compile'
     # /home/bonflintstone/.rvm/gems/ruby-2.3.0/gems/treetop-1.4.12/lib/treetop/compiler/grammar_compiler.rb:24:in `ruby_source_from_string'
     # /home/bonflintstone/.rvm/gems/ruby-2.3.0/gems/treetop-1.4.12/lib/treetop/compiler/grammar_compiler.rb:42:in `load_from_string'
     # /home/bonflintstone/.rvm/gems/ruby-2.3.0/gems/treetop-1.4.12/lib/treetop/compiler/grammar_compiler.rb:35:in `block in load'
     # /home/bonflintstone/.rvm/gems/ruby-2.3.0/gems/treetop-1.4.12/lib/treetop/compiler/grammar_compiler.rb:32:in `open'
     # /home/bonflintstone/.rvm/gems/ruby-2.3.0/gems/treetop-1.4.12/lib/treetop/compiler/grammar_compiler.rb:32:in `load'
     # ./spec/grammars/document_treetop.spec.rb:5:in `block (2 levels) in <top (required)>'

# This file is copied to spec/ when you run 'rails generate rspec:install'
ENV['RAILS_ENV'] ||= 'test'
require File.expand_path('../../config/environment', __FILE__)
# Prevent database truncation if the environment is production
abort("The Rails environment is running in production mode!") if Rails.env.production?
require 'spec_helper'
require 'rspec/rails'
# Add additional requires below this line. Rails is not loaded until this point!

# Requires supporting ruby files with custom matchers and macros, etc, in
# spec/support/ and its subdirectories. Files matching `spec/**/*_spec.rb` are
# run as spec files by default. This means that files in spec/support that end
# in _spec.rb will both be required and run as specs, causing the specs to be
# run twice. It is recommended that you do not name files matching this glob to
# end with _spec.rb. You can configure this pattern with the --pattern
# option on the command line or in ~/.rspec, .rspec or `.rspec-local`.
#
# The following line is provided for convenience purposes. It has the downside
# of increasing the boot-up time by auto-requiring all files in the support
# directory. Alternatively, in the individual `*_spec.rb` files, manually
# require only the support files necessary.
#
# Dir[Rails.root.join('spec/support/**/*.rb')].each { |f| require f }

# Checks for pending migration and applies them before tests are run.
# If you are not using ActiveRecord, you can remove this line.
ActiveRecord::Migration.maintain_test_schema!

RSpec.configure do |config|
  # Remove this line if you're not using ActiveRecord or ActiveRecord fixtures
  config.fixture_path = "#{::Rails.root}/spec/fixtures"

  # If you're not using ActiveRecord, or you'd prefer not to run each of your
  # examples within a transaction, remove the following line or assign false
  # instead of true.
  config.use_transactional_fixtures = true

  # RSpec Rails can automatically mix in different behaviours to your tests
  # based on their file location, for example enabling you to call `get` and
  # `post` in specs under `spec/controllers`.
  #
  # You can disable this behaviour by removing the line below, and instead
  # explicitly tag your specs with their type, e.g.:
  #
  #     RSpec.describe UsersController, :type => :controller do
  #       # ...
  #     end
  #
  # The different available types are documented in the features, such as in
  # https://relishapp.com/rspec/rspec-rails/docs
  config.infer_spec_type_from_file_location!

  # Filter lines from Rails gems in backtraces.
  config.filter_rails_from_backtrace!
  # arbitrary gems may also be filtered via:
  # config.filter_gems_from_backtrace("gem name")
end