require 'spec_helper'
require 'immutable/hash'

describe Immutable::Hash do
  describe '#dig' do
    let(:h) { H[:a => 9, :b => H[:c => 'a', :d => 4], :e => nil] }
    it 'returns the value with one argument to dig' do
      expect(h.dig(:a)).to eq(9)
    end

    it 'returns the value in nested hashes' do
      expect(h.dig(:b, :c)).to eq('a')
    end

    it 'returns nil if the key is not present' do
      expect(h.dig(:f, :foo)).to eq(nil)
    end

    it 'returns nil if you dig out the end of the hash' do
      expect(h.dig(:f, :foo, :bar)).to eq(nil)
    end

    # This is a bit different from Ruby's Hash; it raises TypeError for
    #   objects which don't respond to #dig
    it 'raises a NoMethodError if a value does not support #dig' do
      expect { h.dig(:a, :foo) }.to raise_error(NoMethodError)
    end

    it 'returns the correct value when there is a default proc' do
      default_hash = H.new { |k, v| "#{k}-default" }
      expect(default_hash.dig(:a)).to eq('a-default')
    end
  end
end