From: james_b <james_b@...>
Date: 2003-08-01T10:28:36+09:00
Subject: Test::Unit leaving phanthom objects in ObjectSpace?

I have some code that examines the objects in ObjectSpace and returns a 
set with all those that meet some criteria.  I found during unit testing 
that, although I have just one (global) varible refering to an object of 
a particular type, iterating over ObjectSpace.each_object returns 
numerous objects of this class after some test methods have been called.

My unit test code has this:

   def setup
     $foo = Foo.new( "Test!" )
   end

   def teardown
     $foo = nil
   end

After four test methods are called, ObjectSpace still holds two objects 
of class Foo, although the code only has that one variable for the one 
instance of Foo needed.

Is this a quirk of Test::Unit?  Or of ObjectSpace?

I've tried adding a call to ObjectSpace.garbage_collect
before the iteration, but it doesn't change anything.

This appears to be a Test::Unit quirk because if I call the code outside 
of the  Test::Unit::TestCase subclass then I find no leftover objects.
Direct calls to setup and teardown do not leave any objects around, and 
the call to each_object finds the one item that should be there.

How can I ensure that once teardown is called that there are no extra 
objects lingering in ObjectSpace, short of doing the setup and teardown 
by hand inside of each test method?

I'm using ruby 1.8.0 (2003-05-26) [i386-mswin32] and whatever Test::Unit 
that comes with that (there's no version number in unit.rb)

Thanks,

James Britt