diff --git a/Lib/test/test_unicode.py b/Lib/test/test_unicode.py
index 2ac79fb..285b7af 100644
--- a/Lib/test/test_unicode.py
+++ b/Lib/test/test_unicode.py
@@ -1419,6 +1419,17 @@
         self.assertEquals(size, 7)
         self.assertEquals(wchar, 'abc\0def\0')
 
+        nonbmp = chr(0x10ffff)
+        if sizeof(c_wchar) == 2:
+            buflen = 3
+            nchar = 2
+        else: # sizeof(c_wchar) == 4
+            buflen = 2
+            nchar = 1
+        wchar, size = test_aswidechar(nonbmp, buflen)
+        self.assertEquals(size, nchar)
+        self.assertEquals(wchar, nonbmp + '\0')
+
     # Test PyUnicode_AsWideCharString()
     def test_aswidecharstring(self):
         from _testcapi import test_aswidecharstring
@@ -1432,6 +1443,15 @@
         self.assertEquals(size, 7)
         self.assertEquals(wchar, 'abc\0def\0')
 
+        nonbmp = chr(0x10ffff)
+        if sizeof(c_wchar) == 2:
+            nchar = 2
+        else: # sizeof(c_wchar) == 4
+            nchar = 1
+        wchar, size = test_aswidecharstring(nonbmp)
+        self.assertEquals(size, nchar)
+        self.assertEquals(wchar, nonbmp + '\0')
+
 
 def test_main():
     support.run_unittest(__name__)