diff --git a/testing/util.py b/testing/util.py
index 20a01a0f..40ee389b 100644
--- a/testing/util.py
+++ b/testing/util.py
@@ -66,7 +66,8 @@ xfailif_windows_no_node = pytest.mark.xfail(
 
 
 def platform_supports_pcre():
-    return cmd_output('grep', '-P', '', os.devnull, retcode=None)[0] == 1
+    output = cmd_output('grep', '-P', 'setup', 'setup.py', retcode=None)
+    return output[0] == 0 and 'from setuptools import setup' in output[1]
 
 
 xfailif_no_pcre_support = pytest.mark.xfail(
diff --git a/tests/repository_test.py b/tests/repository_test.py
index 1872033e..6163194b 100644
--- a/tests/repository_test.py
+++ b/tests/repository_test.py
@@ -340,6 +340,7 @@ def test_additional_python_dependencies_installed(tempdir_factory, store):
         assert 'mccabe' in output
 
 
+@xfailif_windows_no_ruby
 @pytest.mark.integration
 def test_additional_ruby_dependencies_installed(tempdir_factory, store):
     path = make_repo(tempdir_factory, 'ruby_hooks_repo')
@@ -352,6 +353,7 @@ def test_additional_ruby_dependencies_installed(tempdir_factory, store):
         assert 'thread_safe' in output
 
 
+@xfailif_windows_no_node
 @pytest.mark.integration
 def test_additional_node_dependencies_installed(tempdir_factory, store):
     path = make_repo(tempdir_factory, 'node_hooks_repo')