Allow PEP517 without setup_requires

When using PBR PEP517 support without setup_requires were were
infinitely recursing because Distribution.finalize_options calls pbr()
and pbr() calls Distribution.finalize_options. With a setup_requires
this doesn't seem to happen because something is resetting dist.pbr's
value from True (callable) to None (not callable) after the initial
pbr() call and before further recursion can occur.

Explicitly enforce this behavior in pbr() via an explicit update of
dist.pbr to None to avoid calling pbr() more than once resulting in the
unwanted loop.

Change-Id: I1f2b4d34e587389f7e11b99d000e14477cf5091b

0 files changed, 0 insertions, 0 deletions