```ruby
require 'test_helper'

class DeployTest < Minitest::Test
  TAG='3.14.15'

  def test_that_it_has_a_version_number
    refute_nil ::Deploy::VERSION
  end

  def test_that_it_requires_arguments
    exception = assert_raises(ArgumentError) { Deploy::Runner.new }
    assert_equal "wrong number of arguments (0 for 1)", exception.message
  end

  def test_that_it_accepts_one_argument
    assert_instance_of Deploy::Runner, Deploy::Runner.new(TAG)
  end

  def test_that_it_only_accepts_one_argument
    exception = assert_raises(ArgumentError) { Deploy::Runner.new(TAG, TAG) }
    assert_match /wrong number of arguments \([\d]+ for 1\)/, exception.message
  end

  def test_that_it_requires_clean_index
    repo = Minitest::Mock.new
    repo.expect :index_modified?, true
    runner = Deploy::Runner.new(TAG)
    runner.stub(:repo, repo) do
      exception = assert_raises(RuntimeError) { runner.run }
      assert_equal "You have staged changes! Please sort your life out mate, innit?",
                   exception.message
    end
  end
end
```

Use require_relative to invoke test helper
user
```ruby
require_relative 'test_helper'

class DeployTest < Minitest::Test
  TAG='3.14.15'

  def test_that_it_has_a_version_number
    refute_nil ::Deploy::VERSION
  end

  def test_that_it_requires_arguments
    exception = assert_raises(ArgumentError) { Deploy::Runner.new }
    assert_equal "wrong number of arguments (0 for 1)", exception.message
  end

  def test_that_it_accepts_one_argument
    assert_instance_of Deploy::Runner, Deploy::Runner.new(TAG)
  end

  def test_that_it_only_accepts_one_argument
    exception = assert_raises(ArgumentError) { Deploy::Runner.new(TAG, TAG) }
    assert_match /wrong number of arguments \([\d]+ for 1\)/, exception.message
  end

  def test_that_it_requires_clean_index
    repo = Minitest::Mock.new
    repo.expect :index_modified?, true
    runner = Deploy::Runner.new(TAG)
    runner.stub(:repo, repo) do
      exception = assert_raises(RuntimeError) { runner.run }
      assert_equal "You have staged changes! Please sort your life out mate, innit?",
                   exception.message
    end
  end
end
```
assistant