Merge branch 'master' into pytest

conftest.py

@@ -6,7 +6,7 @@ from functools import partial
 import pytest
 
 import jedi
-from jedi.api.environment import get_default_environment, get_system_environment
+from jedi.api.environment import get_system_environment, InterpreterEnvironment
 from jedi._compatibility import py_version
 
 collect_ignore = [
@@ -41,6 +41,9 @@ def pytest_addoption(parser):
 
     parser.addoption("--env", action='store',
                      help="Execute the tests in that environment (e.g. 35 for python3.5).")
+    parser.addoption("--interpreter-env", "-I", action='store_true',
+                     help="Don't use subprocesses to guarantee having safe "
+                          "code execution. Useful for debugging.")
 
 
 def pytest_configure(config):
@@ -87,13 +90,13 @@ def clean_jedi_cache(request):
 
 @pytest.fixture(scope='session')
 def environment(request):
+    if request.config.option.interpreter_env:
+        return InterpreterEnvironment()
+
     version = request.config.option.env
     if version is None:
         version = os.environ.get('JEDI_TEST_ENVIRONMENT', str(py_version))
 
-    if int(version) == py_version:
-        return get_default_environment()
-
     return get_system_environment(version[0] + '.' + version[1:])
 
 
@@ -116,3 +119,11 @@ def has_typing(environment):
 @pytest.fixture(scope='session')
 def jedi_path():
     return os.path.dirname(__file__)
+
+
+@pytest.fixture()
+def skip_python2(environment):
+    if environment.version_info.major == 2:
+        # This if is just needed to avoid that tests ever skip way more than
+        # they should for all Python versions.
+        pytest.skip()