#7475: add (un)transform method to bytes/bytearray and str, add back codecs that can be used with them from Python 2.
diff --git a/Doc/library/codecs.rst b/Doc/library/codecs.rst
index dcfc46f..5416d3b 100644
--- a/Doc/library/codecs.rst
+++ b/Doc/library/codecs.rst
@@ -1165,6 +1165,46 @@
| | | operand |
+--------------------+---------+---------------------------+
+The following codecs provide bytes-to-bytes mappings. They can be used with
+:meth:`bytes.transform` and :meth:`bytes.untransform`.
+
++--------------------+---------------------------+---------------------------+
+| Codec | Aliases | Purpose |
++====================+===========================+===========================+
+| base64_codec | base64, base-64 | Convert operand to MIME |
+| | | base64 |
++--------------------+---------------------------+---------------------------+
+| bz2_codec | bz2 | Compress the operand |
+| | | using bz2 |
++--------------------+---------------------------+---------------------------+
+| hex_codec | hex | Convert operand to |
+| | | hexadecimal |
+| | | representation, with two |
+| | | digits per byte |
++--------------------+---------------------------+---------------------------+
+| quopri_codec | quopri, quoted-printable, | Convert operand to MIME |
+| | quotedprintable | quoted printable |
++--------------------+---------------------------+---------------------------+
+| uu_codec | uu | Convert the operand using |
+| | | uuencode |
++--------------------+---------------------------+---------------------------+
+| zlib_codec | zip, zlib | Compress the operand |
+| | | using gzip |
++--------------------+---------------------------+---------------------------+
+
+The following codecs provide string-to-string mappings. They can be used with
+:meth:`str.transform` and :meth:`str.untransform`.
+
++--------------------+---------------------------+---------------------------+
+| Codec | Aliases | Purpose |
++====================+===========================+===========================+
+| rot_13 | rot13 | Returns the Caesar-cypher |
+| | | encryption of the operand |
++--------------------+---------------------------+---------------------------+
+
+.. versionadded:: 3.2
+ bytes-to-bytes and string-to-string codecs.
+
:mod:`encodings.idna` --- Internationalized Domain Names in Applications
------------------------------------------------------------------------
diff --git a/Doc/library/stdtypes.rst b/Doc/library/stdtypes.rst
index b2931ae..6ebf2a0 100644
--- a/Doc/library/stdtypes.rst
+++ b/Doc/library/stdtypes.rst
@@ -1352,6 +1352,19 @@
"They're Bill's Friends."
+.. method:: str.transform(encoding, errors='strict')
+
+ Return an encoded version of the string. In contrast to :meth:`encode`, this
+ method works with codecs that provide string-to-string mappings, and not
+ string-to-bytes mappings. :meth:`transform` therefore returns a string
+ object.
+
+ The codecs that can be used with this method are listed in
+ :ref:`standard-encodings`.
+
+ .. versionadded:: 3.2
+
+
.. method:: str.translate(map)
Return a copy of the *s* where all characters have been mapped through the
@@ -1369,6 +1382,14 @@
example).
+.. method:: str.untransform(encoding, errors='strict')
+
+ Return a decoded version of the string. This provides the reverse operation
+ of :meth:`transform`.
+
+ .. versionadded:: 3.2
+
+
.. method:: str.upper()
Return a copy of the string converted to uppercase.
@@ -1800,6 +1821,20 @@
The maketrans and translate methods differ in semantics from the versions
available on strings:
+.. method:: bytes.transform(encoding, errors='strict')
+ bytearray.transform(encoding, errors='strict')
+
+ Return an encoded version of the bytes object. In contrast to
+ :meth:`encode`, this method works with codecs that provide bytes-to-bytes
+ mappings, and not string-to-bytes mappings. :meth:`transform` therefore
+ returns a bytes or bytearray object.
+
+ The codecs that can be used with this method are listed in
+ :ref:`standard-encodings`.
+
+ .. versionadded:: 3.2
+
+
.. method:: bytes.translate(table[, delete])
bytearray.translate(table[, delete])
@@ -1817,6 +1852,15 @@
b'rd ths shrt txt'
+.. method:: bytes.untransform(encoding, errors='strict')
+ bytearray.untransform(encoding, errors='strict')
+
+ Return an decoded version of the bytes object. This provides the reverse
+ operation of :meth:`transform`.
+
+ .. versionadded:: 3.2
+
+
.. staticmethod:: bytes.maketrans(from, to)
bytearray.maketrans(from, to)