ASP Classic Compiler: the next step

I opened the source code for my ASP Classic Compiler 2 days ago. As this project was started as a research project, proof of concepts has been a major goal. I have cut corners whenever possible to bring out features fast. Going forward, there are many things that need to be tighten up. The following are my top priorities:

1. Unit testing: You eager downloaders may have noticed the my project is notoriously missing unit tests. I intentionally took out my unit tests when I upload because my previous unit tests were not well organized. I want to give us chance of a fresh start. Since we will have refactoring and re-architecture of the code generator, unit testing is going to carry this project. Like many open source projects, NUnit or MSTest is a decision to make. I have created this thread in my forum to solicit ideas. I don’t quite need StackOverflow style discussions as there are already plenty. But if you look at recent high profile switches in either directions, you would know this is not an easy decision.
2. Making it easier for people diagnose problems. A debugger is not going to happen easily, as I have already tried twice. But with source code, it is still possible for people to diagnose problems. This will help reducing the frustration level and getting bug reported and fixed.
3. VBScript 5.0 support. This is my real top goal since many people requested it, but I could not get there without 1 and 2. I want to take over the memory management since I have already pushed DLR to the limit. Controlling the memory management will open up the possibility for debugging. Details is going to be a blog by itself.
4. Performance improvement when calling CLR static methods. The TypeModel used in VBScript.NET does not take advantage of call-site caching and is hence very slow. Fortunately, this can be corrected fairly easily.
5. Optimize for multiple string concatenations. This has been a habit in many ASP projects. I can discover this in code analysis and generate the code behind the scene using StringBuilder. This is a pretty fun research project and it is not too hard.
6. Type checking in many places can still be optimized for callsite-caching.
7. Rewrite of the parser. Currently, my VBScript parser is modified from Paul Vick’s VBParser which was written in VB.NET. I have some concern on VB.NET’s timely availability in new platforms (remember Windows Phone 7?). However, since my code generator is tightly coupled to the abstract syntax tree (AST) in the parser project, this is going to be a messy work.