test_linux.py 文件源码

def test_no_procfs_on_import(self, tb):
        my_procfs = tempfile.mkdtemp()

        with open(os.path.join(my_procfs, 'stat'), 'w') as f:
            f.write('cpu   0 0 0 0 0 0 0 0 0 0\n')
            f.write('cpu0  0 0 0 0 0 0 0 0 0 0\n')
            f.write('cpu1  0 0 0 0 0 0 0 0 0 0\n')

        try:
            orig_open = open

            def open_mock(name, *args, **kwargs):
                if name.startswith('/proc'):
                    raise IOError(errno.ENOENT, 'rejecting access for test')
                return orig_open(name, *args, **kwargs)

            patch_point = 'builtins.open' if PY3 else '__builtin__.open'
            with mock.patch(patch_point, side_effect=open_mock):
                importlib.reload(psutil)
                assert tb.called

                self.assertRaises(IOError, psutil.cpu_times)
                self.assertRaises(IOError, psutil.cpu_times, percpu=True)
                self.assertRaises(IOError, psutil.cpu_percent)
                self.assertRaises(IOError, psutil.cpu_percent, percpu=True)
                self.assertRaises(IOError, psutil.cpu_times_percent)
                self.assertRaises(
                    IOError, psutil.cpu_times_percent, percpu=True)

                psutil.PROCFS_PATH = my_procfs

                self.assertEqual(psutil.cpu_percent(), 0)
                self.assertEqual(sum(psutil.cpu_times_percent()), 0)

                # since we don't know the number of CPUs at import time,
                # we awkwardly say there are none until the second call
                per_cpu_percent = psutil.cpu_percent(percpu=True)
                self.assertEqual(sum(per_cpu_percent), 0)

                # ditto awkward length
                per_cpu_times_percent = psutil.cpu_times_percent(percpu=True)
                self.assertEqual(sum(map(sum, per_cpu_times_percent)), 0)

                # much user, very busy
                with open(os.path.join(my_procfs, 'stat'), 'w') as f:
                    f.write('cpu   1 0 0 0 0 0 0 0 0 0\n')
                    f.write('cpu0  1 0 0 0 0 0 0 0 0 0\n')
                    f.write('cpu1  1 0 0 0 0 0 0 0 0 0\n')

                self.assertNotEqual(psutil.cpu_percent(), 0)
                self.assertNotEqual(
                    sum(psutil.cpu_percent(percpu=True)), 0)
                self.assertNotEqual(sum(psutil.cpu_times_percent()), 0)
                self.assertNotEqual(
                    sum(map(sum, psutil.cpu_times_percent(percpu=True))), 0)
        finally:
            shutil.rmtree(my_procfs)
            importlib.reload(psutil)

        self.assertEqual(psutil.PROCFS_PATH, '/proc')