```ruby
require 'spec_helper'

describe Dotenv::Environment do
  subject { env("OPTION_A=1\nOPTION_B=2") }

  describe 'initialize' do
    it 'reads the file' do
      expect(subject['OPTION_A']).to eq('1')
      expect(subject['OPTION_B']).to eq('2')
    end

    it 'fails if file does not exist' do
      expect {
        Dotenv::Environment.new('.does_not_exists')
      }.to raise_error(Errno::ENOENT)
    end
  end

  describe 'apply' do
    it 'sets variables in ENV' do
      subject.apply
      expect(ENV['OPTION_A']).to eq('1')
    end

    it 'does not override defined variables' do
      ENV['OPTION_A'] = 'predefined'
      subject.apply
      expect(ENV['OPTION_A']).to eq('predefined')
    end
  end

  describe 'apply!' do
    it 'sets variables in the ENV' do
      subject.apply
      expect(ENV['OPTION_A']).to eq('1')
    end

    it 'overrides defined variables' do
      ENV['OPTION_A'] = 'predefined'
      subject.apply!
      expect(ENV['OPTION_A']).to eq('1')
    end
  end

  require 'tempfile'
  def env(text)
    file = Tempfile.new('dotenv')
    file.write text
    file.close
    env = Dotenv::Environment.new(file.path)
    file.unlink
    env
  end
end
```

Call the right method in the spec
user
```ruby
require 'spec_helper'

describe Dotenv::Environment do
  subject { env("OPTION_A=1\nOPTION_B=2") }

  describe 'initialize' do
    it 'reads the file' do
      expect(subject['OPTION_A']).to eq('1')
      expect(subject['OPTION_B']).to eq('2')
    end

    it 'fails if file does not exist' do
      expect {
        Dotenv::Environment.new('.does_not_exists')
      }.to raise_error(Errno::ENOENT)
    end
  end

  describe 'apply' do
    it 'sets variables in ENV' do
      subject.apply
      expect(ENV['OPTION_A']).to eq('1')
    end

    it 'does not override defined variables' do
      ENV['OPTION_A'] = 'predefined'
      subject.apply
      expect(ENV['OPTION_A']).to eq('predefined')
    end
  end

  describe 'apply!' do
    it 'sets variables in the ENV' do
      subject.apply!
      expect(ENV['OPTION_A']).to eq('1')
    end

    it 'overrides defined variables' do
      ENV['OPTION_A'] = 'predefined'
      subject.apply!
      expect(ENV['OPTION_A']).to eq('1')
    end
  end

  require 'tempfile'
  def env(text)
    file = Tempfile.new('dotenv')
    file.write text
    file.close
    env = Dotenv::Environment.new(file.path)
    file.unlink
    env
  end
end
```
assistant