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require File.dirname(__FILE__) + '/../../abstract_unit'
module DelegatingFixtures
class Parent
end
class Child < Parent
superclass_delegating_accessor :some_attribute
end
class Mokopuna < Child
end
end
class DelegatingAttributesTest < Test::Unit::TestCase
include DelegatingFixtures
attr_reader :single_class
def setup
@single_class = Class.new(Object)
end
def test_simple_reader_declaration
single_class.superclass_delegating_reader :only_reader
# The class and instance should have an accessor, but there
# should be no mutator
assert single_class.respond_to?(:only_reader)
assert single_class.public_instance_methods.include?("only_reader")
assert !single_class.respond_to?(:only_reader=)
end
def test_simple_writer_declaration
single_class.superclass_delegating_writer :only_writer
# The class should have a mutator, the instances shouldn't
# neither should have an accessor
assert single_class.respond_to?(:only_writer=)
assert !single_class.public_instance_methods.include?("only_writer=")
assert !single_class.public_instance_methods.include?("only_writer")
assert !single_class.respond_to?(:only_writer)
end
def test_simple_accessor_declaration
single_class.superclass_delegating_accessor :both
# Class should have accessor and mutator
# the instance should have an accessor only
assert single_class.respond_to?(:both)
assert single_class.respond_to?(:both=)
assert single_class.public_instance_methods.include?("both")
assert !single_class.public_instance_methods.include?("both=")
end
def test_working_with_simple_attributes
single_class.superclass_delegating_accessor :both
single_class.both= "HMMM"
assert_equal "HMMM", single_class.both
assert_equal "HMMM", single_class.new.both
end
def test_working_with_accessors
single_class.superclass_delegating_reader :only_reader
single_class.instance_variable_set("@only_reader", "reading only")
assert_equal "reading only", single_class.only_reader
assert_equal "reading only", single_class.new.only_reader
end
def test_working_with_simple_mutators
single_class.superclass_delegating_writer :only_writer
single_class.only_writer="written"
assert_equal "written", single_class.instance_variable_get("@only_writer")
end
def test_child_class_delegates_to_parent_but_can_be_overridden
parent = Class.new
parent.superclass_delegating_accessor :both
child = Class.new(parent)
parent.both= "1"
assert_equal "1", child.both
child.both="2"
assert_equal "1", parent.both
assert_equal "2", child.both
parent.both="3"
assert_equal "3", parent.both
assert_equal "2", child.both
end
def test_delegation_stops_at_the_right_level
assert_nil Mokopuna.some_attribute
assert_nil Child.some_attribute
Child.some_attribute="1"
assert_equal "1", Mokopuna.some_attribute
ensure
Child.some_attribute=nil
end
def test_delegation_stops_for_nil
Mokopuna.some_attribute = nil
Child.some_attribute="1"
assert_equal "1", Child.some_attribute
assert_nil Mokopuna.some_attribute
end
end
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