bpo-16995: add support for base32 extended hex (base32hex) (GH-20441)

cc @pganssle

Automerge-Triggered-By: @pganssle

1 files changed, 70 insertions, 0 deletions

diff --git a/Lib/test/test_base64.py b/Lib/test/test_base64.py
index 1f67e46cd2..4f62c4115f 100644
--- a/Lib/test/test_base64.py
+++ b/Lib/test/test_base64.py
@@ -351,6 +351,76 @@ class BaseXYTestCase(unittest.TestCase):
                 with self.assertRaises(binascii.Error):
                     base64.b32decode(data.decode('ascii'))
 
+    def test_b32hexencode(self):
+        test_cases = [
+            # to_encode, expected
+            (b'',      b''),
+            (b'\x00',  b'00======'),
+            (b'a',     b'C4======'),
+            (b'ab',    b'C5H0===='),
+            (b'abc',   b'C5H66==='),
+            (b'abcd',  b'C5H66P0='),
+            (b'abcde', b'C5H66P35'),
+        ]
+        for to_encode, expected in test_cases:
+            with self.subTest(to_decode=to_encode):
+                self.assertEqual(base64.b32hexencode(to_encode), expected)
+
+    def test_b32hexencode_other_types(self):
+        self.check_other_types(base64.b32hexencode, b'abcd', b'C5H66P0=')
+        self.check_encode_type_errors(base64.b32hexencode)
+
+    def test_b32hexdecode(self):
+        test_cases = [
+            # to_decode, expected, casefold
+            (b'',         b'',      False),
+            (b'00======', b'\x00',  False),
+            (b'C4======', b'a',     False),
+            (b'C5H0====', b'ab',    False),
+            (b'C5H66===', b'abc',   False),
+            (b'C5H66P0=', b'abcd',  False),
+            (b'C5H66P35', b'abcde', False),
+            (b'',         b'',      True),
+            (b'00======', b'\x00',  True),
+            (b'C4======', b'a',     True),
+            (b'C5H0====', b'ab',    True),
+            (b'C5H66===', b'abc',   True),
+            (b'C5H66P0=', b'abcd',  True),
+            (b'C5H66P35', b'abcde', True),
+            (b'c4======', b'a',     True),
+            (b'c5h0====', b'ab',    True),
+            (b'c5h66===', b'abc',   True),
+            (b'c5h66p0=', b'abcd',  True),
+            (b'c5h66p35', b'abcde', True),
+        ]
+        for to_decode, expected, casefold in test_cases:
+            with self.subTest(to_decode=to_decode, casefold=casefold):
+                self.assertEqual(base64.b32hexdecode(to_decode, casefold),
+                                 expected)
+                self.assertEqual(base64.b32hexdecode(to_decode.decode('ascii'),
+                                 casefold), expected)
+
+    def test_b32hexdecode_other_types(self):
+        self.check_other_types(base64.b32hexdecode, b'C5H66===', b'abc')
+        self.check_decode_type_errors(base64.b32hexdecode)
+
+    def test_b32hexdecode_error(self):
+        tests = [b'abc', b'ABCDEF==', b'==ABCDEF', b'c4======']
+        prefixes = [b'M', b'ME', b'MFRA', b'MFRGG', b'MFRGGZA', b'MFRGGZDF']
+        for i in range(0, 17):
+            if i:
+                tests.append(b'='*i)
+            for prefix in prefixes:
+                if len(prefix) + i != 8:
+                    tests.append(prefix + b'='*i)
+        for data in tests:
+            with self.subTest(to_decode=data):
+                with self.assertRaises(binascii.Error):
+                    base64.b32hexdecode(data)
+                with self.assertRaises(binascii.Error):
+                    base64.b32hexdecode(data.decode('ascii'))
+
+
     def test_b16encode(self):
         eq = self.assertEqual
         eq(base64.b16encode(b'\x01\x02\xab\xcd\xef'), b'0102ABCDEF')