I have a control, which I test with a customvalidatortester, that produces an html span with (I thought) style="display:none" and it was failing the test for visible==false.
A closer inspection showed that there was a space after the colon: style="display: none"
Removing the space fixes the problem, but the root of the problem is where the space comes from. The space is inserted when I use Visual Studio 2005's format document on the aspx markup.
To solve this, I mad another small change to NUnitAsp.
In ValidatorTester, I chanbed the visible property to check for both versions.
bool displayNone = (style != null && (style.IndexOf("display:none") != -1 || style.IndexOf("display: none") != -1));