test: rename 'check-code' own test to 'test-contrib-check-code.t'
This test (making sure the 'check-code' script run as intended) have been
confused with the test making that the mercurial code base comply with our
coding still by multiple generations of contributors.
We are moving it out of the way so that all tests starting with
'test-check' are now doing compliance testing.
parsers: check results of PyInt_FromLong (
issue4771)
parsers: simplify error logic in compute_phases_map_sets
Since Py_XDECREF and free both accept NULL pointers, we can get by
with just two exit paths: one for success, and one for error.
This considerably simplifies reasoning about the possible ways to
exit from this function.