Spree::OrderPopulator.populate ordering two items when one requested

Question

I have a program where I am attempting to programatically create Spree orders. I am using the OrderPopulator class to complete this. My code is:

populator = Spree::OrderPopulator.new current_order(create_order_if_necessary: true), current_currency
products.each do |product|
  variant = Spree::Variant.find_by product_id: product.id, is_master: true
  puts "Pre-Items: #{current_order.line_items.count}"
  populator.populate({ products: { product_id: product.id, variant_id: variant.id }, quantity: 1 })
  puts "Post-Items: #{current_order.line_items.count}"
  puts "Products: #{current_order.line_items.first.quantity}"
end

This prints:

Pre-Items: 0
Post-Items: 1
Products: 2

Products should be 1 because that is the quantity I specified when adding the item. What am I doing wrong?

Answer 1

You're confusing products and variants a little bit. In Spree 2.1 we have this bit of code:

https://github.com/spree/spree/blob/v2.1.6/core/app/models/spree/order_populator.rb#L21-L27

It allows you to add in a product and/or a variant. Since you've specified two id's in the products hash, it tries to add the first one (product.id) and the second one (variant.id).

I imagine that your quantity is 2 because your product.id == variant.id.

I'd recommend only adding things by variant ID so try:

populator.populate({ variants: { variant_id: variant.id }, quantity: 1 })

---

Spree 2.2.x has done away with some of this complexity and now populate just takes in a variant id:

https://github.com/spree/spree/blob/v2.2.1/core/app/models/spree/order_populator.rb#L13-L16