framework tests: fix timeout tests

Currently the timeout tests rely on /usr/bin/sleep and /usr/bin/true.
This is very fragile, since on my (Gentoo) system true is in /bin. The
better solution is to rely on either a shell built-in or to just find
the binary in path.

This of course still has some fragility, so this patch also introduces a
new utility function, binary_check. This function looks for a command
using which (not window safe of course, but most of the unit tests
aren't) or it raises a SkipTest.

Signed-off-by: Dylan Baker <dylanx.c.baker@intel.com>

2 files changed, 17 insertions, 2 deletions

diff --git a/framework/tests/exectest_test.py b/framework/tests/exectest_test.py
index 357925186..aaf86a388 100644
--- a/framework/tests/exectest_test.py
+++ b/framework/tests/exectest_test.py
@@ -25,6 +25,7 @@ import nose.tools as nt
 from framework.exectest import PiglitTest, Test
 from framework.log import LogManager
 from framework.dmesg import DummyDmesg
+import framework.tests.utils as utils
 
 
 # Helpers
@@ -61,25 +62,28 @@ def test_run_return_early():
 
 def test_timeout():
     """ Test that Test.timeout works correctly """
+    utils.binary_check('sleep')
 
     def helper():
         if (test.result['returncode'] == 0):
             test.result['result'] = "pass"
 
-    test = TestTest("/usr/bin/sleep 60")
+    test = TestTest("sleep 60")
     test.test_interpret_result = helper
     test.timeout = 1
     test.run()
     assert test.result['result'] == 'timeout'
 
+
 def test_timeout_pass():
     """ Test that the correct result is returned if a test does not timeout """
+    utils.binary_check('true')
 
     def helper():
         if (test.result['returncode'] == 0):
             test.result['result'] = "pass"
 
-    test = TestTest("/usr/bin/true")
+    test = TestTest("true")
     test.test_interpret_result = helper
     test.timeout = 1
     test.run()
diff --git a/framework/tests/utils.py b/framework/tests/utils.py
index 2694fabc8..3b13a1fee 100644
--- a/framework/tests/utils.py
+++ b/framework/tests/utils.py
@@ -29,11 +29,13 @@ import os
 import shutil
 import tempfile
 import functools
+import subprocess
 from contextlib import contextmanager
 try:
     import simplejson as json
 except ImportError:
     import json
+from nose.plugins.skip import SkipTest
 import nose.tools as nt
 import framework.results
 
@@ -252,3 +254,12 @@ class StaticDirectory(object):
     def teardown_class(cls):
         """ Remove the temporary directory """
         shutil.rmtree(cls.tdir)
+
+
+def binary_check(bin_):
+    """Check for the existance of a binary or raise SkipTest."""
+    with open(os.devnull, 'w') as null:
+        try:
+            subprocess.check_call(['which', bin_], stdout=null, stderr=null)
+        except subprocess.CalledProcessError:
+            raise SkipTest('Binary {} not available'.format(bin_))