require_relative 'test_helper'

# Kernel test class
class KernelTest < Minitest::Test
  include FakeFS
  def setup
    FakeFS.deactivate!
  end

  def teardown
    FakeFS.activate!
  end

  def test_can_exec_normally
    out = open("|echo 'foo'")
    assert_equal "foo\n", out.gets
  end

  def test_fake_kernel_can_create_subprocesses
    FakeFS do
      out = open("|echo 'foo'")
      assert_equal "foo\n", out.gets
    end
  end

  def test_fake_kernel_can_create_new_file
    FakeFS do
      FileUtils.mkdir_p '/path/to/'
      open('/path/to/file', 'w') do |f|
        f << 'test'
      end
      assert_kind_of FakeFile, FileSystem.fs['path']['to']['file']
    end
  end

  def test_fake_kernel_can_do_stuff
    FakeFS do
      FileUtils.mkdir_p('/tmp')
      File.open('/tmp/a', 'w+') { |f| f.puts 'test' }

      begin
        open('/tmp/a').read
      rescue StandardError => e
        raise e
      end
    end
  end

  def test_kernel_open_remains_private
    refute 'foo'.respond_to?(:open), 'String#open should be private'
  end

  def test_can_exec_normally2
    out = open("|echo 'foo'")
    assert_equal "foo\n", out.gets
  end
end