tests/testlib/ext-phase-report.py

revlog: update pure nodecache start lookup offset on insertion

test-storage.py is failing in pure builds because the population of the node
cache isn't accounting for the new starting offset after a revlog insertion.

This commit updates the node cache start offset to account for insertions.

I'm not 100% convinced this is the ideal solution. But it works and seems
correct.

Differential Revision: https://phab.mercurial-scm.org/D4996

# tiny extension to report phase changes during transaction

from __future__ import absolute_import

def reposetup(ui, repo):

    def reportphasemove(tr):
        for rev, move in sorted(tr.changes[b'phases'].items()):
            if move[0] is None:
                ui.write((b'test-debug-phase: new rev %d:  x -> %d\n'
                          % (rev, move[1])))
            else:
                ui.write((b'test-debug-phase: move rev %d: %d -> %d\n'
                          % (rev, move[0], move[1])))

    class reportphaserepo(repo.__class__):
        def transaction(self, *args, **kwargs):
            tr = super(reportphaserepo, self).transaction(*args, **kwargs)
            tr.addpostclose(b'report-phase', reportphasemove)
            return tr

    repo.__class__ = reportphaserepo