Fruits!

fruits.rb

require 'rspec'

# The goal is to make the tests pass
# Get the cheapest price for each seller.
# Seller x the priority seller.

# returs a hash containing fruits,
# sub keys under fruits are prices
# and fruit "keys"
def fruits_prices(sellers)
  # sellers is a hash of sellers who have multiple fruits
  cheapest_prices = {}

  sellers.each do |fruits|
    fruits.each do |fruit, info|
      if cheapest_prices[:"#{fruit}"].nil?
        cheapest_prices[:"#{fruit}"] = info

      # you can set the operator to less than (<)
      # if you want to prioritize sellers by
      # order of appearance in params
      elsif info[:price] <= cheapest_prices[:"#{fruit}"][:price]
        cheapest_prices[:"#{fruit}"] = info
      end
    end
  end

  cheapest_prices
end

RSpec.describe "fruits_prices" do

  let(:seller_x_result) { {
    apple: { price: 40, key: 'x-1', additional: 'no children' },
    orange: { price: 40, key: 'x-2' },
    mango: { price: 100, key: 'x-3' },
    grape: { price: 200, key: 'x-4' }
  } }

  let(:seller_y_result)  { {
    apple: { price: 50, key: 'y-1'},
    grape: { price: 170, key: 'y-4'}
  } }

  let(:seller_a_result) { {
    orange: { price: 30, key: 'a-2' },
    mango: { price: 100, key: 'a-3' },
    grape: { price: 140, key: 'a-4' }
  } }

  let(:seller_b_result) { {
    grape: { price: 120, key: 'b-4' },
    lemon: { price: 80, key: 'b-5' }
  } }

  it "works" do
    result = fruits_prices([seller_x_result, seller_y_result, seller_a_result, seller_b_result])
    expect(result[:apple]).to eq(seller_x_result[:apple])
    expect(result[:orange]).to eq(seller_a_result[:orange])

    # if seller_x is priority then the expected result should be seller_x[:mango]
    expect(result[:mango]).to eq(seller_a_result[:mango])
    expect(result[:grape]).to eq(seller_b_result[:grape])
    expect(result[:lemon]).to eq(seller_b_result[:lemon])

    result = fruits_prices([seller_x_result, seller_y_result])
    expect(result[:apple]).to eq(seller_x_result[:apple])
    expect(result[:orange]).to eq(seller_x_result[:orange])
    expect(result[:mango]).to eq(seller_x_result[:mango])
    expect(result[:grape]).to eq(seller_y_result[:grape])

    result = fruits_prices([seller_x_result])
    expect(result).to eq(seller_x_result)
  end
end