Recorded merge of revisions 78508-78509 via svnmerge from

svn+ssh://pythondev@svn.python.org/python/trunk

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  r78508 | florent.xicluna | 2010-02-27 20:20:50 +0100 (sam, 27 fév 2010) | 2 lines

  Clean test_subprocess: use assertRaises, skipIf, skipUnless helpers and a custom helper assertStderrEqual.
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  r78509 | florent.xicluna | 2010-02-27 22:15:27 +0100 (sam, 27 fév 2010) | 2 lines

  Fix an oversight in r78508: p.wait() should be compared to 0
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