add test for cpu_count('usable')

Signed-off-by: Giampaolo Rodola <g.rodola@gmail.com>

1 files changed, 13 insertions, 0 deletions

diff --git a/psutil/tests/test_system.py b/psutil/tests/test_system.py
index 002dd13e..bea1c55b 100755
--- a/psutil/tests/test_system.py
+++ b/psutil/tests/test_system.py
@@ -11,6 +11,7 @@ import datetime
 import errno
 import os
 import pprint
+import random
 import shutil
 import signal
 import socket
@@ -377,6 +378,18 @@ class TestCpuCount(PsutilTestCase):
             self.assertGreaterEqual(cores, 1)
             self.assertGreaterEqual(logical, cores)
 
+    def test_usable(self):
+        if hasattr(psutil.Process, "cpu_affinity"):
+            p = psutil.Process()
+            initial = p.cpu_affinity()
+            assert initial, initial
+            self.addCleanup(p.cpu_affinity, initial)
+            p.cpu_affinity([random.choice(initial)])
+            self.assertEqual(psutil.cpu_count(kind="usable"), 1)
+        else:
+            self.assertEqual(psutil.cpu_count(kind="usable"),
+                             psutil.cpu_count(kind="logical"))
+
     def test_return_none(self):
         # https://github.com/giampaolo/psutil/issues/1085
         for val in (-1, 0, None):