Soon ready to test toolchain

[micttyl]

Are we going to recycle Explorer's testdata for toolchain? If so, doesn't it matter that we cannot accumulate cases that are not implemented in the current Explorer?

[jonmeow]

We haven't implemented the toolchain yet, and may try to share, but right now the testdata is under /explorer because it's tool-specific. If we share test cases, we'd want to put them somewhere else (maybe /common?) and would need to think about sharing of cases.