Getting "wrong number of arguments" error on finder method

Question

I’m using Rails 4.2.3 (and using MySQL 5.5.37). I’m having difficulty writing a finder method for one of my models. I have columns “user,” “object,” and “day”, but the following

  def find_by_user_object_and_day
    respond_to do |format|
      @current_user = User.find(session["user_id"])
      format.js {
        render :text => Userobject.find_by_user_and_object_and_day(:user => @current_user, :object => params[:object], :day => params[:day]) 
      }
    end
  end

produces the error

F, [2016-02-05T16:49:42.934112 #12058] FATAL -- : 
ArgumentError (wrong number of arguments (given 1, expected 3)):
  app/controllers/user_objects_controller.rb:77:in `block (2 levels) in find_by_user_object_and_day'
  app/controllers/user_objects_controller.rb:74:in `find_by_user_object_and_day'

How do I properly specify the arguments to the finder method? I haven’t explicitly defined that finder method because I thought the “and” syntax would work.

Answer 1

The error says:

ArgumentError (wrong number of arguments (given 1, expected 3))

This means you're supposed to pass in 3 distinct arguments, but you passed in 1. It looks like you passed in a hash of values instead of standalone values.

Replace:

 Userobject.find_by_user_and_object_and_day(:user => @current_user, :object => params[:object], :day => params[:day])

With this:

Userobject.find_by_user_and_object_and_day(@current_user, params[:object], params[:day])