Backport fast alternate io.BytesIO implementation.
Merged r62778, r62779, r62802, r62806, r62807, r62808, r62809, r62844,
r62846, r62952, r62956.
diff --git a/Lib/io.py b/Lib/io.py
index 14178d7..0b6907a 100644
--- a/Lib/io.py
+++ b/Lib/io.py
@@ -494,6 +494,7 @@
files, the newlines argument to open can be used to select the line
terminator(s) recognized.
"""
+ self._checkClosed()
if hasattr(self, "peek"):
def nreadahead():
readahead = self.peek(1)
@@ -508,6 +509,8 @@
return 1
if limit is None:
limit = -1
+ if not isinstance(limit, (int, long)):
+ raise TypeError("limit must be an integer")
res = bytearray()
while limit < 0 or len(res) < limit:
b = self.read(nreadahead())
@@ -536,6 +539,10 @@
lines so far exceeds hint.
"""
if hint is None:
+ hint = -1
+ if not isinstance(hint, (int, long)):
+ raise TypeError("hint must be an integer")
+ if hint <= 0:
return list(self)
n = 0
lines = []
@@ -686,7 +693,7 @@
import array
if not isinstance(b, array.array):
raise err
- b[:n] = array.array('b', data)
+ b[:n] = array.array(b'b', data)
return n
def write(self, b):
@@ -729,6 +736,8 @@
if pos is None:
pos = self.tell()
+ # XXX: Should seek() be used, instead of passing the position
+ # XXX directly to truncate?
return self.raw.truncate(pos)
### Flush and close ###
@@ -768,7 +777,7 @@
return self.raw.isatty()
-class BytesIO(BufferedIOBase):
+class _BytesIO(BufferedIOBase):
"""Buffered I/O implementation using an in-memory bytes buffer."""
@@ -777,20 +786,28 @@
def __init__(self, initial_bytes=None):
buf = bytearray()
if initial_bytes is not None:
- buf += initial_bytes
+ buf += bytearray(initial_bytes)
self._buffer = buf
self._pos = 0
def getvalue(self):
"""Return the bytes value (contents) of the buffer
"""
+ if self.closed:
+ raise ValueError("getvalue on closed file")
return bytes(self._buffer)
def read(self, n=None):
+ if self.closed:
+ raise ValueError("read from closed file")
if n is None:
n = -1
+ if not isinstance(n, (int, long)):
+ raise TypeError("argument must be an integer")
if n < 0:
n = len(self._buffer)
+ if len(self._buffer) <= self._pos:
+ return b""
newpos = min(len(self._buffer), self._pos + n)
b = self._buffer[self._pos : newpos]
self._pos = newpos
@@ -807,6 +824,8 @@
if isinstance(b, unicode):
raise TypeError("can't write unicode to binary stream")
n = len(b)
+ if n == 0:
+ return 0
newpos = self._pos + n
if newpos > len(self._buffer):
# Inserts null bytes between the current end of the file
@@ -818,28 +837,38 @@
return n
def seek(self, pos, whence=0):
+ if self.closed:
+ raise ValueError("seek on closed file")
try:
pos = pos.__index__()
except AttributeError as err:
raise TypeError("an integer is required") # from err
if whence == 0:
- self._pos = max(0, pos)
+ if pos < 0:
+ raise ValueError("negative seek position %r" % (pos,))
+ self._pos = pos
elif whence == 1:
self._pos = max(0, self._pos + pos)
elif whence == 2:
self._pos = max(0, len(self._buffer) + pos)
else:
- raise IOError("invalid whence value")
+ raise ValueError("invalid whence value")
return self._pos
def tell(self):
+ if self.closed:
+ raise ValueError("tell on closed file")
return self._pos
def truncate(self, pos=None):
+ if self.closed:
+ raise ValueError("truncate on closed file")
if pos is None:
pos = self._pos
+ elif pos < 0:
+ raise ValueError("negative truncate position %r" % (pos,))
del self._buffer[pos:]
- return pos
+ return self.seek(pos)
def readable(self):
return True
@@ -850,6 +879,16 @@
def seekable(self):
return True
+# Use the faster implementation of BytesIO if available
+try:
+ import _bytesio
+
+ class BytesIO(_bytesio._BytesIO, BufferedIOBase):
+ __doc__ = _bytesio._BytesIO.__doc__
+
+except ImportError:
+ BytesIO = _BytesIO
+
class BufferedReader(_BufferedIOMixin):
@@ -983,6 +1022,12 @@
raise BlockingIOError(e.errno, e.strerror, overage)
return written
+ def truncate(self, pos=None):
+ self.flush()
+ if pos is None:
+ pos = self.raw.tell()
+ return self.raw.truncate(pos)
+
def flush(self):
if self.closed:
raise ValueError("flush of closed file")
@@ -1102,6 +1147,13 @@
else:
return self.raw.tell() - len(self._read_buf)
+ def truncate(self, pos=None):
+ if pos is None:
+ pos = self.tell()
+ # Use seek to flush the read buffer.
+ self.seek(pos)
+ return BufferedWriter.truncate(self)
+
def read(self, n=None):
if n is None:
n = -1
@@ -1150,11 +1202,7 @@
def truncate(self, pos = None):
"""Truncate size to pos."""
- self.flush()
- if pos is None:
- pos = self.tell()
- self.seek(pos)
- return self.buffer.truncate()
+ self._unsupported("truncate")
def readline(self):
"""Read until newline or EOF.
@@ -1351,6 +1399,12 @@
def seekable(self):
return self._seekable
+ def readable(self):
+ return self.buffer.readable()
+
+ def writable(self):
+ return self.buffer.writable()
+
def flush(self):
self.buffer.flush()
self._telling = self._seekable
@@ -1542,7 +1596,16 @@
finally:
decoder.setstate(saved_state)
+ def truncate(self, pos=None):
+ self.flush()
+ if pos is None:
+ pos = self.tell()
+ self.seek(pos)
+ return self.buffer.truncate()
+
def seek(self, cookie, whence=0):
+ if self.closed:
+ raise ValueError("tell on closed file")
if not self._seekable:
raise IOError("underlying stream is not seekable")
if whence == 1: # seek relative to current position
@@ -1629,8 +1692,12 @@
return line
def readline(self, limit=None):
+ if self.closed:
+ raise ValueError("read from closed file")
if limit is None:
limit = -1
+ if not isinstance(limit, (int, long)):
+ raise TypeError("limit must be an integer")
# Grab all the decoded text (we will rewind any extra bits later).
line = self._get_decoded_chars()