Mockers Without Borders
^^^^^
**Definition:**

* Tests demonstrate little rhyme or reason for whether a given test ought to fake a particular dependency or call through to the real thing.


**Code Example:**

.. code-block:: ruby

  # Subject under test
  class App
    def pay_merchants(start_date, end_date)
      transactions = fetch(start_date, end_date)
      purchase_orders = create_purchase_orders(group_by_merchant(transactions))
      submit(purchase_orders)
    end
  end

  # Test
  class MockersWithoutBorders < SmellTest
    def setup
      @subject = App.new
      super
    end

    def test_pays_merchants_with_totals
      transactions = [
        { merchant: 'Nike', desc: 'Shoes', amount: 119.20 },
        { merchant: 'Nike', desc: 'Waterproof spray', amount: 10.10 },
        { merchant: 'Apple', desc: 'iPad', amount: 799.99 },
        { merchant: 'Apple', desc: 'iPad Cover', amount: 59.99 }
      ]
      start_date = Date.civil(2015, 1, 1)
      end_date = Date.civil(2015, 12, 31)
      stub(@subject, :fetch, transactions, [start_date, end_date])
      verify(@subject, :submit, [
        { merchant: 'Nike', total: 129.30 },
        { merchant: 'Apple', total: 859.98 }
      ])

      @subject.pay_merchants(start_date, end_date)
    end
  end

  # Fake production implementations to simplify example test of subject
  class App
    def fetch(start_date, end_date)
      # Imagine something that hits a data store here
    end

    def group_by_merchant(transactions)
      transactions.group_by { |t| t[:merchant] }
    end

    def create_purchase_orders(transactions_by_merchant)
      transactions_by_merchant.map { |(merchant, transactions)|
        {
          merchant: merchant,
          total: transactions.map {|h| h[:amount] }.reduce(:+)
        }
      }
    end

    def submit(purchase_orders)
      # Imagine something that hits a payment processor here
    end
  end

**References:**

.. admonition:: Quality attributes

    * :octicon:`file-code;1em` -  Code Example
    * :octicon:`comment-discussion;1em` -  Cause and Effect
    * :octicon:`graph;1em` -  Frequency
    * :octicon:`sync;1em` -  Refactoring

* `A workbook repository of example test smells and what to do about them <https://github.com/testdouble/test-smells>`_ :octicon:`file-code;1em` :octicon:`comment-discussion;1em` :octicon:`sync;1em`