postcondition.rb

############
## WRONG  ##
############

def some_method
  SomeLongClassName.new(params).perform_action if something_true?

  # a lot of another code
end
  
def create
  redirect_to(root_path) if @resource.save
end
  
##############
##  RIGHT   ##
##############

def some_method
  if something_true?
    SomeLongClassName.new(params).perform_action
  end

  # a lot of another code
end

def create
  if @resource.save
    redirect_to root_path
  end
end