require 'minitest/autorun'
require 'private_attr'

class Dummy
  def read_accessor
    accessor
  end

  def read_accessor_other other
    other.accessor
  end

  def write_accessor value
    self.accessor = value
  end

  def write_accessor_other other, value
    other.accessor = value
  end

  def read_reader
    reader
  end

  def read_reader_other other
    other.reader
  end

  def write_writer value
    self.writer = value
  end

  def write_writer_other other, value
    other.writer = value
  end
end

class PrivateDummy < Dummy
  extend PrivateAttr
  private_attr_accessor :accessor
  private_attr_reader :reader
  private_attr_writer :writer
end

class ProtectedDummy < Dummy
  extend PrivateAttr
  protected_attr_accessor :accessor
  protected_attr_reader :reader
  protected_attr_writer :writer
end

describe PrivateAttr do
  let(:dummy) { dummy_class.new }
  let(:other) { dummy_class.new }
  let(:old_value) { 'old value' }
  let(:value) { 'value' }

  describe 'private_attr_accessor' do
    let(:dummy_class) { PrivateDummy }

    before { dummy.instance_variable_set '@accessor', old_value }

    it 'allows attribute to be read internally' do
      dummy.read_accessor.must_equal old_value
    end

    it 'allows attribute to be written internally' do
      dummy.write_accessor value
      dummy.instance_variable_get('@accessor').must_equal value
    end

    it 'raises Error when read externally' do
      -> { dummy.accessor }.must_raise NoMethodError
    end

    it 'raises Error when written externally' do
      -> { dummy.accessor = value }.must_raise NoMethodError
    end

    it 'raises Error when read by other' do
      -> { dummy.read_accessor_other other }.must_raise NoMethodError
    end

    it 'raises Error when written by other' do
      -> { dummy.write_accessor_other other, value }.must_raise NoMethodError
    end
  end

  describe 'private_attr_reader' do
    let(:dummy_class) { PrivateDummy }

    before { dummy.instance_variable_set '@reader', old_value }

    it 'allows attribute to be read internally' do
      dummy.read_reader.must_equal old_value
    end

    it 'raises Error when written internally' do
      -> { dummy.write_reader value }.must_raise NoMethodError
    end

    it 'raises Error when read externally' do
      -> { dummy.reader }.must_raise NoMethodError
    end

    it 'raises Error when written externally' do
      -> { dummy.reader = value }.must_raise NoMethodError
    end

    it 'raises Error when read by other' do
      -> { dummy.read_reader_other other }.must_raise NoMethodError
    end

    it 'raises Error when written by other' do
      -> { dummy.write_reader_other other, value }.must_raise NoMethodError
    end
  end

  describe 'private_attr_writer' do
    let(:dummy_class) { PrivateDummy }

    before { dummy.instance_variable_set '@writer', old_value }

    it 'raises Error when read internally' do
      -> { dummy.read_writer }.must_raise NoMethodError
    end

    it 'allows attribute to be written internally' do
      dummy.write_writer value
      dummy.instance_variable_get('@writer').must_equal value
    end

    it 'raises Error when read externally' do
      -> { dummy.writer }.must_raise NoMethodError
    end

    it 'raises Error when written externally' do
      -> { dummy.writer = value }.must_raise NoMethodError
    end

    it 'raises Error when read by other' do
      -> { dummy.read_writer_other other }.must_raise NoMethodError
    end

    it 'raises Error when written by other' do
      -> { dummy.write_writer_other other, value }.must_raise NoMethodError
    end
  end

  describe 'protected_attr_accessor' do
    let(:dummy_class) { ProtectedDummy }

    before { dummy.instance_variable_set '@accessor', old_value }

    it 'allows attribute to be read internally' do
      dummy.read_accessor.must_equal old_value
    end

    it 'allows attribute to be written internally' do
      dummy.write_accessor value
      dummy.instance_variable_get('@accessor').must_equal value
    end

    it 'raises Error when read externally' do
      -> { dummy.accessor }.must_raise NoMethodError
    end

    it 'raises Error when written externally' do
      -> { dummy.accessor = value }.must_raise NoMethodError
    end

    it 'allows attribute to be read by other' do
      other.instance_variable_set '@accessor', value
      dummy.read_accessor_other(other).must_equal value
    end

    it 'allows attribute to be written by other' do
      dummy.write_accessor_other other, value
      other.instance_variable_get('@accessor').must_equal value
    end
  end

  describe 'protected_attr_reader' do
    let(:dummy_class) { ProtectedDummy }

    before { dummy.instance_variable_set '@reader', old_value }

    it 'allows attribute to be read internally' do
      dummy.read_reader.must_equal old_value
    end

    it 'raises Error when written internally' do
      -> { dummy.write_reader value }.must_raise NoMethodError
    end

    it 'raises Error when read externally' do
      -> { dummy.reader }.must_raise NoMethodError
    end

    it 'raises Error when written externally' do
      -> { dummy.reader = value }.must_raise NoMethodError
    end

    it 'allows attribute to be read by other' do
      other.instance_variable_set '@reader', value
      dummy.read_reader_other(other).must_equal value
    end

    it 'raises Error when written by other' do
      -> { dummy.write_reader_other other, value }.must_raise NoMethodError
    end
  end

  describe 'protected_attr_writer' do
    let(:dummy_class) { ProtectedDummy }

    before { dummy.instance_variable_set '@writer', old_value }

    it 'raises Error when read internally' do
      -> { dummy.read_writer }.must_raise NoMethodError
    end

    it 'allows attribute to be written internally' do
      dummy.write_writer value
      dummy.instance_variable_get('@writer').must_equal value
    end

    it 'raises Error when read externally' do
      -> { dummy.writer }.must_raise NoMethodError
    end

    it 'raises Error when written externally' do
      -> { dummy.writer = value }.must_raise NoMethodError
    end

    it 'raises Error when read by other' do
      -> { dummy.read_writer_other other }.must_raise NoMethodError
    end

    it 'allows attribute to be written by other' do
      dummy.write_writer_other other, value
      other.instance_variable_get('@writer').must_equal value
    end
  end

  describe 'method visibility' do
    it 'extending classes does not increase their public APIs' do
      PrivateDummy.public_methods.wont_include :private_attr_accessor
    end
  end
end