From aca50d203f176c060236720e749f1d83dfe9152c 2021-12-01 22:47:23
From: 007vedant <raghuvedant00@gmail.com>
Date: 2021-12-01 22:47:23
Subject: [PATCH] Added test for _userlist_pprint
 - all tests passed

---

diff --git a/IPython/lib/tests/test_pretty.py b/IPython/lib/tests/test_pretty.py
index 8b8a6ee..ca16924 100644
--- a/IPython/lib/tests/test_pretty.py
+++ b/IPython/lib/tests/test_pretty.py
@@ -5,7 +5,7 @@
 # Distributed under the terms of the Modified BSD License.
 
 
-from collections import Counter, defaultdict, deque, OrderedDict
+from collections import Counter, defaultdict, deque, OrderedDict, UserList
 import os
 import pytest
 import types
@@ -294,6 +294,42 @@ def test_basic_class():
     assert type_pprint_wrapper.called is True
 
 
+def test_collections_userlist():
+    # Create userlist with cycle
+    a = UserList()
+    a.append(a)
+
+    cases = [
+        (UserList(), "UserList([])"),
+        (
+            UserList(i for i in range(1000, 1020)),
+            "UserList([1000,\n"
+            "          1001,\n"
+            "          1002,\n"
+            "          1003,\n"
+            "          1004,\n"
+            "          1005,\n"
+            "          1006,\n"
+            "          1007,\n"
+            "          1008,\n"
+            "          1009,\n"
+            "          1010,\n"
+            "          1011,\n"
+            "          1012,\n"
+            "          1013,\n"
+            "          1014,\n"
+            "          1015,\n"
+            "          1016,\n"
+            "          1017,\n"
+            "          1018,\n"
+            "          1019])",
+        ),
+        (a, "UserList([UserList(...)])"),
+    ]
+    for obj, expected in cases:
+        assert pretty.pretty(obj) == expected
+
+
 # TODO : pytest.mark.parametrise once nose is gone.
 def test_collections_defaultdict():
     # Create defaultdicts with cycles