pexpect: test failed on pypy3

Not sure why. test_interaction() in tests/test_interaction.py is failing on pypy3 on Travis CI:

=================================== FAILURES ===================================
_______________________________ test_interaction _______________________________
    @pytest.mark.skipif(sys.platform == 'win32',
                        reason="pexpect doesn't work well on Windows")
    @pytest.mark.slow
    def test_interaction():
        bin_path = get_http_prompt_path()
        child = pexpect.spawn(bin_path)

        # TODO: Test more interaction

        child.sendline('exit')
>       child.expect_exact('Goodbye!', timeout=20)
tests/test_interaction.py:19: 
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
../../../virtualenv/pypy3-2.4.0/site-packages/pexpect/spawnbase.py:390: in expect_exact
    return exp.expect_loop(timeout)
../../../virtualenv/pypy3-2.4.0/site-packages/pexpect/expect.py:107: in expect_loop
    return self.timeout(e)
_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 
self = <pexpect.expect.Expecter object at 0x0000000004e456e0>
err = TIMEOUT('Timeout exceeded.',)
    def timeout(self, err=None):
        spawn = self.spawn
        from . import TIMEOUT

        spawn.before = spawn.buffer
        spawn.after = TIMEOUT
        index = self.searcher.timeout_index
        if index >= 0:
            spawn.match = TIMEOUT
            spawn.match_index = index
            return index
        else:
            spawn.match = None
            spawn.match_index = None
            msg = str(spawn)
            msg += '\nsearcher: %s' % self.searcher
            if err is not None:
                msg = str(err) + '\n' + msg
>           raise TIMEOUT(msg)
E           pexpect.exceptions.TIMEOUT: Timeout exceeded.
E           <pexpect.pty_spawn.spawn object at 0x0000000004e45248>
E           command: /home/travis/virtualenv/pypy3-2.4.0/bin/http-prompt
E           args: ['/home/travis/virtualenv/pypy3-2.4.0/bin/http-prompt']
E           buffer (last 100 chars): b'exit\r\nVersion: 0.2.0\r\n'
E           before (last 100 chars): b'exit\r\nVersion: 0.2.0\r\n'
E           after: <class 'pexpect.exceptions.TIMEOUT'>
E           match: None
E           match_index: None
E           exitstatus: None
E           flag_eof: False
E           pid: 2532
E           child_fd: 11
E           closed: False
E           timeout: 30
E           delimiter: <class 'pexpect.exceptions.EOF'>
E           logfile: None
E           logfile_read: None
E           logfile_send: None
E           maxread: 2000
E           ignorecase: False
E           searchwindowsize: None
E           delaybeforesend: 0.05
E           delayafterclose: 0.1
E           delayafterterminate: 0.1
E           searcher: searcher_string:
E               0: "b'Goodbye!'"
../../../virtualenv/pypy3-2.4.0/site-packages/pexpect/expect.py:70: TIMEOUT

See full log at https://travis-ci.org/eliangcs/http-prompt/jobs/133855030.