From: "Jon A. Lambert" <jlsysinc@...>
Date: 2005-05-07T09:51:48+09:00
Subject: Re: Typo-checking instead of static typing

Ben Giddings wrote:
> On Friday 06 May 2005 15:09, Ryan Leavengood wrote:
>> Absolutely. In fact, this should be the norm. When you consider edge
>> cases and a good sampling of non-edge cases, the unit test can
>> quickly outgrow the code being tested.
>> 
>> It may seem like a lot of work, but that work continues to pay off
>> everytime you run the tests, especially after code changes or
>> refactorings.
> 
> Ok, so in this case, what would the unit tests be?
> 
> Ben

This one is rather tricky.
I assume your do_something is part of a Foo class.
I then do a hack to mock up puts to put it in a global

So your tests might look like this:

require 'test/unit'
require 'Foo'

class Foo
 def puts(x)
   $x << x.to_s << "\n"
 end  
end   

class TestFoo < Test::Unit::TestCase
  def setup
    @f = Foo.new
    $x = ""
  end
 
  def test_do_something_0
   @f.do_something(0)
    assert_equal("",$x)
  end

  def test_do_something_3
    @f.do_something(3)
    assert_equal("0\n1\n2\n",$x)
 end
 
  def test_do_something_501
    @f.do_something(501)
    assert_equal("Whoa, 501 is too many times!  I can't do that!\n",$x)
  end
  
  def test_do_something_nil
    @f.do_something(nil)
    assert_equal("",$x)
  end
  
end

There may be an easier way.  *shrug*

--
J. Lambert