python3Packages.virtualenv: enable tests

pkgs/development/python-modules/virtualenv/default.nix

@@ -1,18 +1,26 @@
 { buildPythonPackage
-, fetchPypi
-, lib
-, stdenv
-, pythonOlder
-, isPy27
 , appdirs
 , contextlib2
+, cython
 , distlib
+, fetchPypi
 , filelock
+, fish
+, flaky
 , importlib-metadata
 , importlib-resources
+, isPy27
+, lib
 , pathlib2
+, pytest-freezegun
+, pytest-mock
+, pytest-timeout
+, pytestCheckHook
+, pythonOlder
 , setuptools_scm
 , six
+, stdenv
+, xonsh
 }:
 
 buildPythonPackage rec {
@@ -47,10 +55,33 @@ buildPythonPackage rec {
     ./0001-Check-base_prefix-and-base_exec_prefix-for-Python-2.patch
   ];
 
-  meta = {
+  checkInputs = [
+    cython
+    fish
+    flaky
+    pytest-freezegun
+    pytest-mock
+    pytest-timeout
+    pytestCheckHook
+  ] ++ lib.optionals (pythonOlder "3.9") [
+    xonsh
+  ];
+
+  preCheck = "export HOME=$(mktemp -d)";
+
+  # Ignore tests which requires network access
+  pytestFlagsArray = [
+    "--ignore tests/unit/create/test_creator.py"
+    "--ignore tests/unit/seed/embed/test_bootstrap_link_via_app_data.py"
+  ];
+
+  disabledTests = [ "test_can_build_c_extensions" ];
+  pythonImportsCheck = [ "virtualenv" ];
+
+  meta = with lib; {
     description = "A tool to create isolated Python environments";
     homepage = "http://www.virtualenv.org";
-    license = lib.licenses.mit;
+    license = licenses.mit;
-    maintainers = with lib.maintainers; [ goibhniu ];
+    maintainers = with maintainers; [ goibhniu ];
   };
 }