tests/svn-safe-append.py

tests: update some clonebundles expectations to pass on both pure and non-pure

Specifically, zstd isn't available in --pure mode, and we need to glob
off the leading comma as well as the absent compression engine.

Differential Revision: https://phab.mercurial-scm.org/D859

#!/usr/bin/env python

from __future__ import absolute_import

__doc__ = """Same as `echo a >> b`, but ensures a changed mtime of b.
Without this svn will not detect workspace changes."""

import os
import sys

text = sys.argv[1]
fname = sys.argv[2]

f = open(fname, "ab")
try:
    before = os.fstat(f.fileno()).st_mtime
    f.write(text)
    f.write("\n")
finally:
    f.close()
inc = 1
now = os.stat(fname).st_mtime
while now == before:
    t = now + inc
    inc += 1
    os.utime(fname, (t, t))
    now = os.stat(fname).st_mtime