[Python-Dev] peps: Update PEP 399 to include comments from python-dev.

[James Y Knight]

On Apr 12, 2011, at 7:50 PM, Tres Seaver wrote:
> Trying to accelerate existing code which doesn't have the coverage is
> insane:  how can you know that the accelerator doesn't subtly change the
> semantics without tests?

But even if you do have 100% python source code branch coverage, that's not nearly enough. There are thousands of branches inside the python interpreter, which you also need to have full coverage on to *really* ensure that the behavior of the code does not subtly change.

Good luck with that.

James