Playing around with SVN and google code

[eluser]adamp1[/eluser]
I have one more question about the use of SVN and development, how does everyone use SVN in conjunction with developing the code? What I mean is this, If I have my code in the SVN how can I write new code and test it but use the SVN to keep track of changes?

Should I write the code and check its all valid php on a development system, and when I am happy add it to the SVN, OR is it possible to test it directly on the SVN.