#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/Lib/codecs.py b/Lib/codecs.py
index f6c2448..b150d64 100644
--- a/Lib/codecs.py
+++ b/Lib/codecs.py
@@ -396,6 +396,8 @@
class StreamReader(Codec):
+ charbuffertype = str
+
def __init__(self, stream, errors='strict'):
""" Creates a StreamReader instance.
@@ -417,9 +419,8 @@
self.stream = stream
self.errors = errors
self.bytebuffer = b""
- # For str->str decoding this will stay a str
- # For str->unicode decoding the first read will promote it to unicode
- self.charbuffer = ""
+ self._empty_charbuffer = self.charbuffertype()
+ self.charbuffer = self._empty_charbuffer
self.linebuffer = None
def decode(self, input, errors='strict'):
@@ -455,7 +456,7 @@
"""
# If we have lines cached, first merge them back into characters
if self.linebuffer:
- self.charbuffer = "".join(self.linebuffer)
+ self.charbuffer = self._empty_charbuffer.join(self.linebuffer)
self.linebuffer = None
# read until we get the required number of characters (if available)
@@ -498,7 +499,7 @@
if chars < 0:
# Return everything we've got
result = self.charbuffer
- self.charbuffer = ""
+ self.charbuffer = self._empty_charbuffer
else:
# Return the first chars characters
result = self.charbuffer[:chars]
@@ -529,7 +530,7 @@
return line
readsize = size or 72
- line = ""
+ line = self._empty_charbuffer
# If size is given, we call read() only once
while True:
data = self.read(readsize, firstline=True)
@@ -537,7 +538,8 @@
# If we're at a "\r" read one extra character (which might
# be a "\n") to get a proper line ending. If the stream is
# temporarily exhausted we return the wrong line ending.
- if data.endswith("\r"):
+ if (isinstance(data, str) and data.endswith("\r")) or \
+ (isinstance(data, bytes) and data.endswith(b"\r")):
data += self.read(size=1, chars=1)
line += data
@@ -563,7 +565,8 @@
line0withoutend = lines[0].splitlines(False)[0]
if line0withend != line0withoutend: # We really have a line end
# Put the rest back together and keep it until the next call
- self.charbuffer = "".join(lines[1:]) + self.charbuffer
+ self.charbuffer = self._empty_charbuffer.join(lines[1:]) + \
+ self.charbuffer
if keepends:
line = line0withend
else:
@@ -574,7 +577,7 @@
if line and not keepends:
line = line.splitlines(False)[0]
break
- if readsize<8000:
+ if readsize < 8000:
readsize *= 2
return line
@@ -603,7 +606,7 @@
"""
self.bytebuffer = b""
- self.charbuffer = ""
+ self.charbuffer = self._empty_charbuffer
self.linebuffer = None
def seek(self, offset, whence=0):