diff --git a/tests/test_requests.py b/tests/test_requests.py
index 650ffc8b..7a92926c 100755
--- a/tests/test_requests.py
+++ b/tests/test_requests.py
@@ -2093,6 +2093,7 @@ class TestPreparingURLs(object):
         (
             ('http://google.com', 'http://google.com/'),
             (u'http://ジェーピーニック.jp', u'http://xn--hckqz9bzb1cyrb.jp/'),
+            (u'http://xn--n3h.net/', u'http://xn--n3h.net/'),
             (
                 u'http://ジェーピーニック.jp'.encode('utf-8'),
                 u'http://xn--hckqz9bzb1cyrb.jp/'
@@ -2113,6 +2114,18 @@ class TestPreparingURLs(object):
                 u'http://Königsgäßchen.de/straße'.encode('utf-8'),
                 u'http://xn--knigsgchen-b4a3dun.de/stra%C3%9Fe'
             ),
+            (
+                b'http://xn--n3h.net/',
+                u'http://xn--n3h.net/'
+            ),
+            (
+                b'http://[1200:0000:ab00:1234:0000:2552:7777:1313]:12345/',
+                u'http://[1200:0000:ab00:1234:0000:2552:7777:1313]:12345/'
+            ),
+            (
+                u'http://[1200:0000:ab00:1234:0000:2552:7777:1313]:12345/',
+                u'http://[1200:0000:ab00:1234:0000:2552:7777:1313]:12345/'
+            )
         )
     )
     def test_preparing_url(self, url, expected):
@@ -2127,6 +2140,7 @@ class TestPreparingURLs(object):
             b"http://*",
             u"http://*.google.com",
             u"http://*",
+            u"http://☃.net/"
         )
     )
     def test_preparing_bad_url(self, url):
diff --git a/tests/test_utils.py b/tests/test_utils.py
index 56d5ea6f..c92c7323 100644
--- a/tests/test_utils.py
+++ b/tests/test_utils.py
@@ -17,6 +17,7 @@ from requests.utils import (
     to_key_val_list, to_native_string,
     unquote_header_value, unquote_unreserved,
     urldefragauth, add_dict_to_cookiejar)
+from requests._internal_utils import unicode_is_ascii
 
 from .compat import StringIO, cStringIO
 
@@ -515,6 +516,7 @@ def test_should_bypass_proxies(url, expected, monkeypatch):
     monkeypatch.setenv('NO_PROXY', '192.168.0.0/24,127.0.0.1,localhost.localdomain,172.16.1.1')
     assert should_bypass_proxies(url) == expected
 
+
 @pytest.mark.parametrize(
     'cookiejar', (
         compat.cookielib.CookieJar(),
@@ -529,3 +531,14 @@ def test_add_dict_to_cookiejar(cookiejar):
     cj = add_dict_to_cookiejar(cookiejar, cookiedict)
     cookies = dict((cookie.name, cookie.value) for cookie in cj)
     assert cookiedict == cookies
+
+
+@pytest.mark.parametrize(
+    'value, expected', (
+                (u'test', True),
+                (u'æíöû', False),
+                (u'ジェーピーニック', False),
+    )
+)
+def test_unicode_is_ascii(value, expected):
+    assert unicode_is_ascii(value) is expected