require 'test_helper'

module Vedeu

  describe Collection do

    let(:described)  { Collection }
    let(:instance)   { described.new(collection, parent, model_name) }
    let(:collection) { [] }
    let(:model_name) { 'elements' }
    let(:parent)     { Vedeu::ModelTestClass.new }

    describe '#initialize' do
      it { instance.must_be_instance_of(Collection) }
      it { instance.instance_variable_get('@collection').must_equal([]) }
      it { instance.instance_variable_get('@name').must_equal(model_name) }
      it { instance.instance_variable_get('@parent').must_equal(parent) }
    end

    describe '#[]' do
      let(:collection) { [:hydrogen, :helium, :lithium, :beryllium] }
      let(:_value) { 1..2 }

      subject { instance[_value] }

      it { subject.must_be_instance_of(Array) }
      it { subject.must_equal([:helium, :lithium]) }
    end

    describe '#add' do
      subject { instance.add(:hydrogen) }

      it { subject.must_be_instance_of(Collection) }
      it { subject.all.must_equal([:hydrogen]) }

      context 'with multiple objects' do
        subject { instance.add(:hydrogen, :helium) }

        it 'adds all the objects to the collection' do
          subject.all.must_equal([:hydrogen, :helium])
        end
      end
    end

    describe '#all' do
      subject { instance.all }

      it { subject.must_be_instance_of(Array) }
      it { subject.must_equal([]) }

      context 'when the collection is not empty' do
        before { instance.add(:hydrogen) }

        it 'returns the populated collection' do
          subject.must_equal([:hydrogen])
        end
      end
    end

    describe '#empty?' do
      subject { instance.empty? }

      context 'when the collection is empty' do
        it { subject.must_be_instance_of(TrueClass) }
      end

      context 'when the collection is not empty' do
        before { instance.add(:hydrogen) }

        it { subject.must_be_instance_of(FalseClass) }
      end
    end

    describe '#size' do
      subject { instance.size }

      it { subject.must_be_instance_of(Fixnum) }

      context 'when the collection is empty' do
        it { subject.must_equal(0) }
      end

      context 'when the collection is not empty' do
        before { instance.add(:hydrogen) }

        it { subject.must_equal(1) }
      end
    end

    describe '#to_s' do
      subject { instance.to_s }

      it { subject.must_be_instance_of(String) }

      context 'when the collection is empty' do
        it { subject.must_equal('') }
      end

      context 'when the collection is not empty' do
        before { instance.add(:hydrogen) }

        it { subject.must_equal('hydrogen') }
      end
    end

  end # Collection

end # Vedeu