Make the subprocesses work and return the right sys paths for the different versions

test/test_api/test_environment.py

@@ -1,5 +1,26 @@
-from jedi.api.virtualenv import Environment, DefaultEnvironment
+import pytest
+
+from jedi._compatibility import py_version
+from jedi.api.virtualenv import Environment, DefaultEnvironment, NoVirtualEnv
 
 
 def test_sys_path():
     assert DefaultEnvironment('/foo').get_sys_path()
+
+
+@pytest.mark.parametrize(
+    'version',
+    ['2.6', '2.7', '3.3', '3.4', '3.5', '3.6', '3.7']
+)
+def test_versions(version):
+    executable = 'python' + version
+    try:
+        env = Environment('some path', executable)
+    except NoVirtualEnv:
+        if int(version.replace('.', '')) == py_version:
+            # At least the current version has to work
+            raise
+        return
+
+    sys_path = env.get_sys_path()
+    assert any(executable in p for p in sys_path)