diff --git a/tests/TODO b/tests/TODO.txt
similarity index 94%
rename from tests/TODO
rename to tests/TODO.txt
index d34b7c99c..538e8537b 100644
--- a/tests/TODO
+++ b/tests/TODO.txt
@@ -17,6 +17,10 @@ test_aliases.py
 
 
 test_builtins.py
+----------------
+- Env fixture
+
+
 test_contexts.py
 test_dirstack.py
 test_environ.py
diff --git a/tests/test_builtins.py b/tests/test_builtins.py
index ab7aabd15..11f2e6996 100644
--- a/tests/test_builtins.py
+++ b/tests/test_builtins.py
@@ -11,9 +11,11 @@ from xonsh.built_ins import reglob, pathsearch, helper, superhelper, \
     ensure_list_of_strs, list_of_strs_or_callables, regexsearch, \
     globsearch
 from xonsh.environ import Env
-from xonsh.tools import ON_WINDOWS
 
-from tools import mock_xonsh_env
+from tools import skip_if_on_windows
+
+
+HOME_PATH = os.path.expanduser('~')
 
 
 def test_reglob_tests():
@@ -21,77 +23,72 @@ def test_reglob_tests():
     for f in testfiles:
         assert (f.startswith('test_'))
 
-@pytest.mark.skipif(ON_WINDOWS, reason='Unix stuff')
-def test_repath_backslash():
-    home = os.path.expanduser('~')
-    built_ins.ENV = Env(HOME=home)
-    with mock_xonsh_env(built_ins.ENV):
-        exp = os.listdir(home)
-        exp = {p for p in exp if re.match(r'\w\w.*', p)}
-        exp = {os.path.join(home, p) for p in exp}
-        obs = set(pathsearch(regexsearch, r'~/\w\w.*'))
-        assert exp ==  obs
+@pytest.fixture
+def env():
+    e = Env(HOME=os.path.expanduser('~'))
+    built_ins.ENV = e
+    return e
 
-@pytest.mark.skipif(ON_WINDOWS, reason='Unix stuff')
-def test_repath_home_itself():
-    exp = os.path.expanduser('~')
-    built_ins.ENV = Env(HOME=exp)
-    with mock_xonsh_env(built_ins.ENV):
-        obs = pathsearch(regexsearch, '~')
-        assert 1 ==  len(obs)
-        assert exp ==  obs[0]
 
-@pytest.mark.skipif(ON_WINDOWS, reason='Unix stuff')
-def test_repath_home_contents():
-    home = os.path.expanduser('~')
-    built_ins.ENV = Env(HOME=home)
-    with mock_xonsh_env(built_ins.ENV):
-        exp = os.listdir(home)
-        exp = {os.path.join(home, p) for p in exp}
-        obs = set(pathsearch(regexsearch, '~/.*'))
-        assert exp ==  obs
+@skip_if_on_windows
+@pytest.mark.parametrize('xenv', [Env(HOME=HOME_PATH)])
+def test_repath_backslash(xonsh_env):
+    exp = os.listdir(HOME_PATH)
+    exp = {p for p in exp if re.match(r'\w\w.*', p)}
+    exp = {os.path.join(HOME_PATH, p) for p in exp}
+    obs = set(pathsearch(regexsearch, r'~/\w\w.*'))
+    assert exp ==  obs
 
-@pytest.mark.skipif(ON_WINDOWS, reason='Unix stuff')
-def test_repath_home_var():
-    exp = os.path.expanduser('~')
-    built_ins.ENV = Env(HOME=exp)
-    with mock_xonsh_env(built_ins.ENV):
-        obs = pathsearch(regexsearch, '$HOME')
-        assert 1 ==  len(obs)
-        assert exp ==  obs[0]
+@skip_if_on_windows
+@pytest.mark.parametrize('xenv', [Env(HOME=os.path.expanduser('~'))])
+def test_repath_HOME_PATH_itself(xonsh_env):
+    obs = pathsearch(regexsearch, '~')
+    assert 1 ==  len(obs)
+    assert exp ==  obs[0]
 
-@pytest.mark.skipif(ON_WINDOWS, reason='Unix stuff')
-def test_repath_home_var_brace():
-    exp = os.path.expanduser('~')
-    built_ins.ENV = Env(HOME=exp)
-    with mock_xonsh_env(built_ins.ENV):
-        obs = pathsearch(regexsearch, '${"HOME"}')
-        assert 1 ==  len(obs)
-        assert exp ==  obs[0]
 
-def test_helper_int():
-    with mock_xonsh_env({}):
-        helper(int, 'int')
+@skip_if_on_windows
+@pytest.mark.parametrize('xenv', [Env(HOME=os.path.expanduser('~'))])
+def test_repath_HOME_PATH_contents(xonsh_env):
+    exp = os.listdir(HOME_PATH)
+    exp = {os.path.join(HOME_PATH, p) for p in exp}
+    obs = set(pathsearch(regexsearch, '~/.*'))
+    assert exp ==  obs
 
-def test_helper_helper():
-    with mock_xonsh_env({}):
-        helper(helper, 'helper')
 
-def test_helper_env():
-    with mock_xonsh_env({}):
-        helper(Env, 'Env')
+@skip_if_on_windows
+@pytest.mark.parametrize('xenv', [Env(HOME=os.path.expanduser('~'))])
+def test_repath_HOME_PATH_var(xonsh_env):
+    obs = pathsearch(regexsearch, '$HOME')
+    assert 1 ==  len(obs)
+    assert exp ==  obs[0]
 
-def test_superhelper_int():
-    with mock_xonsh_env({}):
-        superhelper(int, 'int')
 
-def test_superhelper_helper():
-    with mock_xonsh_env({}):
-        superhelper(helper, 'helper')
+@skip_if_on_windows
+@pytest.mark.parametrize('xenv', [Env(HOME=os.path.expanduser('~'))])
+def test_repath_HOME_PATH_var_brace(xonsh_env):
+    obs = pathsearch(regexsearch, '${"HOME"}')
+    assert 1 ==  len(obs)
+    assert exp ==  obs[0]
 
-def test_superhelper_env():
-    with mock_xonsh_env({}):
-        superhelper(Env, 'Env')
+
+def test_helper_int(xonsh_env):
+    helper(int, 'int')
+
+def test_helper_helper(xonsh_env):
+    helper(helper, 'helper')
+
+def test_helper_env(xonsh_env):
+    helper(Env, 'Env')
+
+def test_superhelper_int(xonsh_env):
+    superhelper(int, 'int')
+
+def test_superhelper_helper(xonsh_env):
+    superhelper(helper, 'helper')
+
+def test_superhelper_env(xonsh_env):
+    superhelper(Env, 'Env')
 
 def test_ensure_list_of_strs():
     cases = [(['yo'], 'yo'), (['yo'], ['yo']), (['42'], 42), (['42'], [42])]
diff --git a/tests/test_tools.py b/tests/test_tools.py
index 9f62dadfd..0dd15affc 100644
--- a/tests/test_tools.py
+++ b/tests/test_tools.py
@@ -572,7 +572,6 @@ def expand(path):
     (b'~/../', '~/../'),
 ])
 def test_env_path_getitem(inp, exp, xonsh_env):
-    # lambda to expand the expected paths
     obs = EnvPath(inp)[0] # call to __getitem__
     assert expand(exp) == obs