batchitemprocessor_spec.rb

# http://www.codewars.com/kata/batchitemprocessor/ruby
require './batchitemprocessor'

class Test
  # This class mimics the one provided in the kata
  def self.assert_equals(actual, expected, message="")
    if actual!=expected
      puts "\nTest '#{message}' failed.\nExpected #{expected}\nGot #{actual}"
    else
      puts "."
    end
  end
end

# You can run these tests in the kata by ignoring everything above this line

def test(message)
  yield(message)
end

def test_processed(message, items)
  bip = BatchItemProcessor.new
  yield(bip)
  Test.assert_equals(bip.processed_items,items,message)
end

test "processed_items returns an array of items processed" do |message|
  bip = BatchItemProcessor.new
  bip.process_items([1,2]){}
  Test.assert_equals(bip.processed_items,[1,2],message)
end

test "Processes all items if none are already processed" do |message|
  processed = []
  BatchItemProcessor.new.process_items([1,2,3,4]) do |item|
    processed << item
  end
  Test.assert_equals(processed,[1,2,3,4],message)
end

test "Ignores items already processed" do |message|
  processed = []
  logItem = ->(item){processed << item}
  bip = BatchItemProcessor.new
  bip.process_items([1,2,3,4], &logItem)
  bip.process_items([3,4,5,6], &logItem)
  Test.assert_equals(processed,[1,2,3,4,5,6],message)
end

test_processed "Only processes items when should_process returns true", [2] do |bip|
  bip.should_process(&:even?)
  bip.process_items([1,2]){}
end

test_processed "reset clears processed item state", [] do |bip|
  bip.process_items([1,2]){}
  bip.reset
end

[["symbol",:length], ["string","length"]].each do |type, method|
  test_processed "uses identify(#{type}) to compare objects", ["a", "aa"] do |bip|
    bip.identify(method)
    bip.process_items(["a","b","aa","bb"]){}
  end
end

test_processed "uses identify to compare hashes", [{id:1,name:"a"}] do |bip|
  bip.identify(:id)
  bip.process_items([{id:1,name:"a"},{id:1,name:"b"}]){}
end

test_processed "correctly handles nil being processed and not processed again", [nil] do |bip|
  bip.process_items([nil,nil]){}
end