Issue #12591: Allow io.TextIOWrapper to work with raw IO objects (without
a read1() method), and add an undocumented *write_through* parameter to
mandate unbuffered writes.
diff --git a/Lib/_pyio.py b/Lib/_pyio.py
index b79d5fc..78c6d95 100644
--- a/Lib/_pyio.py
+++ b/Lib/_pyio.py
@@ -1472,7 +1472,7 @@
_CHUNK_SIZE = 2048
def __init__(self, buffer, encoding=None, errors=None, newline=None,
- line_buffering=False):
+ line_buffering=False, write_through=False):
if newline is not None and not isinstance(newline, str):
raise TypeError("illegal newline type: %r" % (type(newline),))
if newline not in (None, "", "\n", "\r", "\r\n"):
@@ -1515,6 +1515,7 @@
self._decoded_chars_used = 0 # offset into _decoded_chars for read()
self._snapshot = None # info for reconstructing decoder state
self._seekable = self._telling = self.buffer.seekable()
+ self._has_read1 = hasattr(self.buffer, 'read1')
if self._seekable and self.writable():
position = self.buffer.tell()
@@ -1680,7 +1681,10 @@
# len(dec_buffer) bytes ago with decoder state (b'', dec_flags).
# Read a chunk, decode it, and put the result in self._decoded_chars.
- input_chunk = self.buffer.read1(self._CHUNK_SIZE)
+ if self._has_read1:
+ input_chunk = self.buffer.read1(self._CHUNK_SIZE)
+ else:
+ input_chunk = self.buffer.read(self._CHUNK_SIZE)
eof = not input_chunk
self._set_decoded_chars(self._decoder.decode(input_chunk, eof))