Bad syntax in model validation throws error in controller

[bplmp]

Steps to reproduce

1. Create a Product model with this validation which has bad syntax: validates_uniqueness_of :code, :scope => [:archived => false]
2. Try to update any attribute for Product.

Expected behavior

An error that points to the bad syntax in the model validation for Product.

Actual behavior

Throws the following error undefined method 'to_sym' for {:archived=>false}:Hash Did you mean? to_s to_yaml to_set.

The error points to the if @product.update(product_params) line in the ProductsController. Full update method is:

  def update
    @product = Product.find(params[:id])
  
    if @product.update(product_params)
      redirect_to @product
    else
      render 'edit'
    end
  end

System configuration

Rails version:
rails (5.0.0.1)

Ruby version:
ruby 2.3.0p0

Has been discussed in this Stack Overflow question.

[rafaelfranca]

I think we should check if scope is a symbol when calling validates_uniqueness_of . Could you open a PR?