word_tracker.rb

require 'pry'

class WordTracker

	attr_reader :words

	def initialize(words)
		@words = words
		@frequency = Hash.new(0)
	end

	def frequency
		collection.each do |word|
			@frequency[word.downcase] += 1
		end
		@frequency
	end

	def collection
		@words.split(' ')
	end

end

WordTracker.new('Toy boat toy boat toy boat').frequency

word_tracker_spec.rb

require 'rspec'
require_relative 'word_tracker'

describe WordTracker do

	it 'calculates the frequency of each word' do
		expect(WordTracker.new('Toy boat toy boat toy boat').frequency).to eql ({
 		 "toy" => 3,
 		 "boat" => 3
		})
	end

	it 'should should seperate the words' do
		expect(WordTracker.new('Toy boat toy boat toy boat').collection).to eql (['Toy','boat','toy','boat','toy','boat'])
	end

	it 'should have words' do
		expect(WordTracker.new('Toy boat toy boat toy boat').words).to eql ('Toy boat toy boat toy boat')
	end

end