sample_spec.rb

describe 'remove_duplicates' do
  it 'removes duplicates' do
    expect(remove_duplicates [-2, 12, 33, -2, 42, -2, 4, 8, 4, 13, 12]).
      to eq [-2, 12, 33, 42, 4, 8, 13]
    expect(remove_duplicates [-1, 4, -1, 33, 33, 42, 4]).
      to eq [-1, 4, 33, 42]
    expect(remove_duplicates [0, 7, 8, 7, 8, 78, 0, 2, 4, 6]).
      to eq [0, 7, 8, 78, 2, 4, 6]
  end
  it 'returns empty array' do
    expect(remove_duplicates []).
      to eq []
  end
end