1 files changed, 27 insertions, 0 deletions
diff --git a/Lib/test/test_pyrepl/test_utils.py b/Lib/test/test_pyrepl/test_utils.py
new file mode 100644
index 00000000000..0d59968206a
--- /dev/null
+++ b/Lib/test/test_pyrepl/test_utils.py
@@ -0,0 +1,27 @@
+from unittest import TestCase
+
+from _pyrepl.utils import str_width, wlen
+
+
+class TestUtils(TestCase):
+    def test_str_width(self):
+        characters = ['a', '1', '_', '!', '\x1a', '\u263A', '\uffb9']
+        for c in characters:
+            self.assertEqual(str_width(c), 1)
+
+        characters = [chr(99989), chr(99999)]
+        for c in characters:
+            self.assertEqual(str_width(c), 2)
+
+    def test_wlen(self):
+        for c in ['a', 'b', '1', '!', '_']:
+            self.assertEqual(wlen(c), 1)
+        self.assertEqual(wlen('\x1a'), 2)
+
+        char_east_asian_width_N = chr(3800)
+        self.assertEqual(wlen(char_east_asian_width_N), 1)
+        char_east_asian_width_W = chr(4352)
+        self.assertEqual(wlen(char_east_asian_width_W), 2)
+
+        self.assertEqual(wlen('hello'), 5)
+        self.assertEqual(wlen('hello' + '\x1a'), 7)