1require "spec_helper"
 2
 3describe MergeSort do
 4  subject { MergeSort.new }
 5
 6  it "should sort an empty array" do
 7    expect(subject.sort([])).to eq([])
 8  end
 9
10  it "should sort an array with one item" do
11    expect(subject.sort([2])).to eq([2])
12  end
13
14  it "should sort an array of numbers" do
15    n = 601
16    numbers = Array.new(n) { rand(n) }
17    sorted_numbers = numbers.sort
18    expect(subject.sort(numbers)).to eq(sorted_numbers)
19  end
20end