require 'rspec'
require File.join(File.dirname(__FILE__), '..', 'lib/string_calculator')

describe StringCalculator do
  subject { described_class.new }

  it 'returns 0 if empty string provided' do
    expect(subject.add("")).to eq(0)
  end
end

require 'rspec'
require File.join(File.dirname(__FILE__), '..', 'lib/string_calculator')

describe StringCalculator do
  subject { described_class.new }

  it 'returns 0 if empty string provided' do
    expect(subject.add("")).to eq(0)
  end

  it 'returns number if one number provided' do
    expect(subject.add("1")).to eq(1)
  end
end

Test case for one number provided
Test case for one number provided
