test failure in test_close_initiating_remote_no_error[sys.executable]

Hi,

in an attempt to package execnet for openSUSE, our build fails with:

[   18s] =================================== FAILURES ===================================
[   18s] ____________ test_close_initiating_remote_no_error[sys.executable] _____________
[   18s] 
[   18s] testdir = <Testdir local('/tmp/pytest-of-abuild/pytest-3/test_close_initiating_remote_no_error0')>
[   18s] anypython = local('/usr/bin/python2')
[   18s] 
[   18s]     def test_close_initiating_remote_no_error(testdir, anypython):
[   18s]         p = testdir.makepyfile("""
[   18s]             import sys
[   18s]             sys.path.insert(0, sys.argv[1])
[   18s]             import execnet
[   18s]             gw = execnet.makegateway("popen")
[   18s]             print ("remote_exec1")
[   18s]             ch1 = gw.remote_exec("channel.receive()")
[   18s]             print ("remote_exec1")
[   18s]             ch2 = gw.remote_exec("channel.receive()")
[   18s]             print ("termination")
[   18s]             execnet.default_group.terminate()
[   18s]         """)
[   18s]         testdir.makepyfile(apipkg=apipkg)
[   18s]         popen = subprocess.Popen(
[   18s]             [str(anypython), str(p), str(execnetdir)],
[   18s]             stdout=None, stderr=subprocess.PIPE,)
[   18s]         out, err = popen.communicate()
[   18s]         print (err)
[   18s]         err = err.decode('utf8')
[   18s]         lines = [
[   18s]             x for x in err.splitlines()
[   18s]             if '*sys-package' not in x]
[   18s]         # print (lines)
[   18s] >       assert not lines
[   18s] E       assert not ['Traceback (most recent call last):', '  File "/tmp/pytest-of-abuild/pytest-3/test_close_initiating_remote_no_error0/... '  File "/tmp/pytest-of-abuild/pytest-3/test_close_initiating_remote_no_error0/apipkg.py", line 12, in <module>', ...]

Full build log here:
https://build.opensuse.org/package/live_build_log/devel:languages:python/python-execnet/openSUSE_Tumbleweed/x86_64

It looks like some unexpected interaction with apipkg and python 2.7.
Shouldn't this test being excluded for 2.7 then, or do you have other ideas, what's going wrong?

Our build facility attempts to build the package for 2.7 and 3.* by default, depending on the build target.

Start with test_close_initiating_remote_no_error[sys.executable] and reproduce the openSUSE failure under Python 2.7 with apipkg. Read the complete traceback to identify the incompatibility; done means the test passes on supported Python versions or its Python 2.7 handling is explicitly resolved and covered by the test suite.