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Story Two Tests

NOTE: I going to deviate a bit from actuall events at this point. What really happened is that Mark and I made wholesale changes to our tests to support the new syntax. Then we implemented the new syntax for the net object. I think I can do the change more incrementally and will present the series of changes here.

The first test adds support for the basic indexing operation. 

# file: testnet.rb
...
  def test_tied
    assert_equal true, ! @net.tied?(1,1)
    assert_equal :EMPTY, @net[1,1]          # NEW
  end
...

The implementation was straight forward 

# file: net.rb
...
  def [](x,y)
    @tied[x-1][y-1]
  end
...

But the tests gave this error ...

  
...
Failure occurred in test_tied(TestNet) [testnet.rb:12]: Expected <EMPTY> but was <false>
...

This can be fixed by initializing the array to :EMPTY instead of false. But this will cause the tied? method to break (it is expected to return a true/false value). So we fix that as well. 

# file: net.rb
...
  def initialize
    @tied = (1..MAXSIZE).collect {
      (1..MAXSIZE).collect {:EMPTY}
    }
  end
...

I though that would work, but the tests report ...

  
$ ruby testnet.rb
Loaded suite testnet
Started...
..
Failure occurred in test_max_matrix_size(TestNet) [testnet.rb:46]: Expected <false> but was <true>
....
Failure occurred in test_untie(TestNet) [testnet.rb:31]: Expected <false> but was <true>

Finished in 0.063337 seconds.
5 runs, 11 assertions, 2 failures, 0 errors

Checking the tests, we discover that the untie method stores a false value. We will need to change this. 

# file: net.rb
...
  def untie(x,y)
    @tied[x-1][y-1] = :EMPTY
  end
...

And the tests are OK once again. On to the next step.

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