[Distutils] PEP 517 again

[Paul Moore]

On 26 August 2017 at 03:17, Guido van Rossum <guido at python.org> wrote:
> In pretty much any other context, if you have an operation that returns an
> regular value or an error value, the error value should be None. (Exceptions
> include e.g. returning a non-negative int or -1 for errors, or True for
> success and False for errors.)

So, given that build_sdist returns the path of the newly built sdist,
the correct way to signal "I didn't manage to build a sdist" would be
to return None.

Now that it's put this way, it seems glaringly obvious to me that this
is the correct thing to do.
Paul