```ruby
require File.dirname(__FILE__) + '/../abstract_unit'

class DurationTest < Test::Unit::TestCase
  def test_inspect
    assert_equal '1 month',                         1.month.inspect
    assert_equal '1 month and 1 day',               (1.month + 1.day).inspect
    assert_equal '6 months and -2 days',            (6.months - 2.days).inspect
    assert_equal '10 seconds',                      10.seconds.inspect
    assert_equal '10 years, 2 months, and 1 day',   (10.years + 2.months + 1.day).inspect
    assert_equal '7 days',                          1.week.inspect
    assert_equal '14 days',                         1.fortnight.inspect
  end
  
  def test_minus_with_duration_does_not_break_subtraction_of_date_from_date
    assert_nothing_raised { Date.today - Date.today }
  end
  
  def test_plus_with_time
    assert_equal 1 + 1.second, 1.second + 1, "Duration + Numeric should == Numeric + Duration"
  end
end
```

Mark Duration test failing with Ruby 1.9
user
```ruby
require File.dirname(__FILE__) + '/../abstract_unit'

class DurationTest < Test::Unit::TestCase
  def test_inspect
    assert_equal '1 month',                         1.month.inspect
    assert_equal '1 month and 1 day',               (1.month + 1.day).inspect
    assert_equal '6 months and -2 days',            (6.months - 2.days).inspect
    assert_equal '10 seconds',                      10.seconds.inspect
    assert_equal '10 years, 2 months, and 1 day',   (10.years + 2.months + 1.day).inspect
    assert_equal '7 days',                          1.week.inspect
    assert_equal '14 days',                         1.fortnight.inspect
  end

  def test_minus_with_duration_does_not_break_subtraction_of_date_from_date
    assert_nothing_raised { Date.today - Date.today }
  end

  # FIXME: ruby 1.9
  def test_plus_with_time
    assert_equal 1 + 1.second, 1.second + 1, "Duration + Numeric should == Numeric + Duration"
  end
end
```
assistant