Rspec Binary Search

rspec_binary_search.rb

describe 'binatry_search' do
  let(:test_array_1) { [1, 2, 3, 4, 5, 6, 7, 8, 9, 10] }
  let(:test_array_2) { (1..100).to_a }
  
  let(:test_object_1) { 3 }
  let(:test_object_2) { 10 }
  let(:test_object_3) { 39 }  
  let(:test_object_4) { 97 }
  
  it 'is defined' do
    defined?(binary_search).should eq 'method'
  end
  
  it 'requires two arguements' do
    method(:binary_search).arity.should eq 2
  end
  
  it 'raises an error if 2nd argument is not an array' do
    expect { binary_search("a", "b") }.to raise_error
  end
  
  it 'returns the correct object in a small array' do
    binary_search(test_object_1, test_array_1).should eq 2
    binary_search(test_object_2, test_array_1).should eq 9
  end
  
  it 'returns the correct object in a larger array' do
    binary_search(test_object_3, test_array_2).should eq 38
    binary_search(test_object_4, test_array_2).should eq 96
  end