ruby-koans/about_objects.rb
2023-12-27 00:25:48 +05:30

51 lines
1.3 KiB
Ruby

require File.expand_path(File.dirname(__FILE__) + '/neo')
class AboutObjects < Neo::Koan
def test_everything_is_an_object
assert_equal true, 1.is_a?(Object)
assert_equal true, 1.5.is_a?(Object)
assert_equal true, "string".is_a?(Object)
assert_equal true, nil.is_a?(Object) # like JS?
assert_equal true, Object.is_a?(Object)
end
def test_objects_can_be_converted_to_strings
assert_equal "123", 123.to_s
assert_equal "", nil.to_s
end
def test_objects_can_be_inspected
assert_equal '123', 123.inspect
assert_equal "nil", nil.inspect
end
def test_every_object_has_an_id
obj = Object.new
assert_equal Integer, obj.object_id.class
end
def test_every_object_has_different_id
obj = Object.new
another_obj = Object.new
assert_equal true, obj.object_id != another_obj.object_id
end
def test_small_integers_have_fixed_ids
assert_equal 1, 0.object_id # pattern is id = value + (value + 1)
assert_equal 3, 1.object_id
assert_equal 5, 2.object_id
assert_equal 201, 100.object_id
# THINK ABOUT IT:
# What pattern do the object IDs for small integers follow?
end
def test_clone_creates_a_different_object
obj = Object.new
copy = obj.clone
assert_equal true, obj != copy
assert_equal true, obj.object_id != copy.object_id
end
end