Add coverage test for Travis CI workaround

testing/test_plugin.py

@@ -45,6 +45,11 @@ def test_auto_detect_cpus(testdir, monkeypatch):
     config = testdir.parseconfigure("-nauto")
     assert config.getoption('numprocesses') == 99
 
+    if not hasattr(os, 'sched_getaffinity'):
+        monkeypatch.setenv('TRAVIS', 'true')
+        config = testdir.parseconfigure("-nauto")
+        assert config.getoption('numprocesses') == 2
+
 
 def test_boxed_with_collect_only(testdir):
     from xdist.plugin import pytest_cmdline_main as check_options