Reproducible test framework

I am looking for a test or integration framework that supports long, costly tests for correctness. The tests should only be rerun if the code affecting the test has changed.

Ideally the test framework would

• find the code of the test
• produce a hash of it,
• run the code and write to an output file with the hash as the name
• or skip if that already exists.
• provide a simple overview what tests succeeded and which failed.

It would be OK if the test has to specify the modules and files it depends on.

Python would be ideal, but this problem may be high-level enough that other languages would work too.

Perhaps there exists already a test or build integration framework I can adapt to fit this behaviour?