test_webclient.py 文件源码

def testDownloadPageError3(self):
        # make sure failures in open() are caught too. This is tricky.
        # Might only work on posix.
        tmpfile = open("unwritable", "wb")
        tmpfile.close()
        os.chmod("unwritable", 0) # make it unwritable (to us)
        d = self.assertFailure(
            client.downloadPage(self.getURL("file"), "unwritable"),
            IOError)
        d.addBoth(self._cleanupDownloadPageError3)
        return d