require 'spec_helper'

describe Monolens, 'object.transform' do
  context 'with default options' do
    subject do
      Monolens.lens('object.transform' => {
        defn: { firstname: 'str.upcase' }
      })
    end

    it 'works as expected' do
      expect(subject.call(firstname: 'Bernard')).to eql(firstname: 'BERNARD')
    end

    it 'works as expected on an object with String keys' do
      expect(subject.call('firstname' => 'Bernard')).to eql('firstname' => 'BERNARD')
    end

    it 'raises an error if input object does not have a key' do
      expect {
        subject.call(lastname: 'Lambeau')
      }.to raise_error(Monolens::LensError, /firstname/)
    end
  end

  context 'with on_missing: skip' do
    subject do
      Monolens.lens('object.transform' => {
        on_missing: :skip,
        defn: { firstname: 'str.upcase' }
      })
    end

    it 'works as expected' do
      expect(subject.call(firstname: 'Bernard')).to eql(firstname: 'BERNARD')
    end

    it 'skpis if missing' do
      expect(subject.call(lastname: 'Lambeau')).to eql(lastname: 'Lambeau')
    end
  end

  context 'with on_missing: null' do
    subject do
      Monolens.lens('object.transform' => {
        on_missing: :null,
        defn: { firstname: 'str.upcase' }
      })
    end

    it 'works as expected' do
      expect(subject.call(firstname: 'Bernard')).to eql(firstname: 'BERNARD')
    end

    it 'skpis if missing' do
      expect(subject.call(lastname: 'Lambeau')).to eql(firstname: nil, lastname: 'Lambeau')
    end
  end

  describe 'error traceability' do
    let(:lens) do
      Monolens.lens({
        'array.map' => {
          :lenses => {
            'object.transform' => {
              defn: { firstname: 'str.upcase' }
            }
          }
        }
      })
    end

    subject do
      lens.call(input)
      nil
    rescue Monolens::LensError => ex
      ex
    end

    context 'when missing key' do
      let(:input) do
        [{}]
      end

      it 'correctly updates the location' do
        expect(subject.location).to eql([0])
      end
    end

    context 'when an error down the line' do
      let(:input) do
        [{
          firstname: nil
        }]
      end

      it 'correctly updates the location' do
        expect(subject.location).to eql([0, :firstname])
      end
    end
  end
end