tests/svn-safe-append.py

tests: avoid nested quoting on command line for portability

Before this patch, test-revset.t fails on Solaris using ksh as default
"sh", because nested quoting below isn't acceptable for it.

                +-----------------------------+ inner quoting
    "`python -c "print '|'.join(['0:1'] * 500)"`"
    +-------------------------------------------+ outer quoting

This patch does below for portability.

  - omit outer quoting

    This should be safe, because generated string contains no white
    space character.

  - use '+' instead of '|' (for safety)

    '|' has special meaning for many shell, but '+' isn't (at least,
    for ordinary ones).

#!/usr/bin/env python

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

import sys, os

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