diff --git a/Lib/test/test_unicode.py b/Lib/test/test_unicode.py
index 591a297..259a181 100644
--- a/Lib/test/test_unicode.py
+++ b/Lib/test/test_unicode.py
@@ -1767,6 +1767,42 @@
             ]])
         self.assertRaises(TypeError, _string.formatter_field_name_split, 1)
 
+    def test_encode_decimal(self):
+        from _testcapi import unicode_encodedecimal
+        self.assertEqual(unicode_encodedecimal('123'),
+                         b'123')
+        self.assertEqual(unicode_encodedecimal('\u0663.\u0661\u0664'),
+                         b'3.14')
+        self.assertEqual(unicode_encodedecimal("\N{EM SPACE}3.14\N{EN SPACE}"),
+                         b' 3.14 ')
+        self.assertRaises(UnicodeEncodeError,
+                          unicode_encodedecimal, "123\u20ac", "strict")
+        self.assertEqual(unicode_encodedecimal("123\u20ac", "replace"),
+                         b'123?')
+        self.assertEqual(unicode_encodedecimal("123\u20ac", "ignore"),
+                         b'123')
+        self.assertEqual(unicode_encodedecimal("123\u20ac", "xmlcharrefreplace"),
+                         b'123&#8364;')
+        self.assertEqual(unicode_encodedecimal("123\u20ac", "backslashreplace"),
+                         b'123\\u20ac')
+        self.assertEqual(unicode_encodedecimal("123\u20ac\N{EM SPACE}", "replace"),
+                         b'123? ')
+        self.assertEqual(unicode_encodedecimal("123\u20ac\u20ac", "replace"),
+                         b'123??')
+        self.assertEqual(unicode_encodedecimal("123\u20ac\u0660", "replace"),
+                         b'123?0')
+
+    def test_transform_decimal(self):
+        from _testcapi import unicode_transformdecimaltoascii as transform_decimal
+        self.assertEqual(transform_decimal('123'),
+                         '123')
+        self.assertEqual(transform_decimal('\u0663.\u0661\u0664'),
+                         '3.14')
+        self.assertEqual(transform_decimal("\N{EM SPACE}3.14\N{EN SPACE}"),
+                         "\N{EM SPACE}3.14\N{EN SPACE}")
+        self.assertEqual(transform_decimal('123\u20ac'),
+                         '123\u20ac')
+
 
 def test_main():
     support.run_unittest(__name__)