require 'spec_helper'

describe Immutable::List do
  [:each_chunk, :each_slice].each do |method|
    describe "##{method}" do
      context 'on a really big list' do
        it "doesn't run out of stack" do
          -> { BigList.send(method, 1) { |item| } }.should_not raise_error
        end
      end

      [
        [[], []],
        [['A'], [L['A']]],
        [%w[A B C], [L['A', 'B'], L['C']]],
      ].each do |values, expected|
        context "on #{values.inspect}" do
          let(:list) { L[*values] }

          context 'with a block' do
            it 'preserves the original' do
              list.should eql(L[*values])
            end

            it 'iterates over the items in order' do
              yielded = []
              list.send(method, 2) { |item| yielded << item }
              yielded.should eql(expected)
            end

            it 'returns self' do
              list.send(method, 2) { |item| item }.should be(list)
            end
          end

          context 'without a block' do
            it 'preserves the original' do
              list.send(method, 2)
              list.should eql(L[*values])
            end

            it 'returns an Enumerator' do
              list.send(method, 2).class.should be(Enumerator)
              list.send(method, 2).to_a.should eql(expected)
            end
          end
        end
      end
    end
  end
end
