'Verify that "py-bt" displays invocations of PyCFunction instances'

@unittest.skipIf(python_is_optimized(), 'Python    was    compiled    with    optimizations')
@unittest.skipUnless(_thread, 'Python    was    compiled    without    thread    support')
def test_pycfunction(self):

    cmd = 'from    time    import    sleep\ndef    foo():\n                sleep(1)\ndef    bar():\n                foo()\nbar()\n'
    gdb_output = self.get_stack_trace(cmd, breakpoint='time_sleep', cmds_after_breakpoint=['bt', 'py-bt'])
    self.assertIn('<built-in    method    sleep', gdb_output)
    gdb_output = self.get_stack_trace(cmd, breakpoint='time_sleep', cmds_after_breakpoint=['py-bt-full'])
    self.assertIn('#0    <built-in    method    sleep', gdb_output)
