diff --git a/tests/test_cmd.py b/tests/test_cmd.py
index 882a528..7a09210 100644
--- a/tests/test_cmd.py
+++ b/tests/test_cmd.py
@@ -1,3 +1,4 @@
+import platform
 from unittest import TestCase, skipIf, skip
 
 import os
@@ -284,6 +285,10 @@ def test_auto_init(self):  # pragma: no cover
 
 
 @skipIf(not MercurialDvcsCmd.available(), 'mercurial is not available')
+@skipIf(
+    platform.python_implementation() != 'CPython',
+    'only doing mercurial tests with CPython',
+)
 class MercurialDvcsCmdTestCase(CoreTestCase, RawCmdTests):
     cmdcls = MercurialDvcsCmd