truncate() returns the new size and position.
write() returns the number of bytes/characters written/buffered.
FileIO.close() calls self.flush().
Implement readinto() for buffered readers.
Tests th check all these.
Test proper behavior of __enter__/__exit__.
diff --git a/Lib/io.py b/Lib/io.py
index 69c6c20..9c6738a 100644
--- a/Lib/io.py
+++ b/Lib/io.py
@@ -177,10 +177,11 @@
"""tell() -> int. Return current stream position."""
return self.seek(0, 1)
- def truncate(self, pos: int = None) -> None:
- """truncate(size: int = None) -> None. Truncate file to size bytes.
+ def truncate(self, pos: int = None) -> int:
+ """truncate(size: int = None) -> int. Truncate file to size bytes.
Size defaults to the current IO position as reported by tell().
+ Returns the new size.
"""
self._unsupported("truncate")
@@ -329,6 +330,10 @@
would be hard to do since _fileio.c is written in C).
"""
+ def close(self):
+ _fileio._FileIO.close(self)
+ RawIOBase.close(self)
+
class SocketIO(RawIOBase):
@@ -413,7 +418,10 @@
Raises BlockingIOError if the underlying raw stream has no
data at the moment.
"""
- self._unsupported("readinto")
+ data = self.read(len(b))
+ n = len(data)
+ b[:n] = data
+ return n
def write(self, b: bytes) -> int:
"""write(b: bytes) -> int. Write the given buffer to the IO stream.
@@ -448,7 +456,7 @@
return self.raw.tell()
def truncate(self, pos=None):
- self.raw.truncate(pos)
+ return self.raw.truncate(pos)
### Flush and close ###
@@ -503,12 +511,6 @@
self._pos = newpos
return b
- def readinto(self, b):
- tmp = self.read(len(b))
- n = len(tmp)
- b[:n] = tmp
- return n
-
def write(self, b):
n = len(b)
newpos = self._pos + n
@@ -536,6 +538,7 @@
else:
self._pos = max(0, pos)
del self._buffer[pos:]
+ return pos
def readable(self):
return True
@@ -652,7 +655,6 @@
def write(self, b):
# XXX we can implement some more tricks to try and avoid partial writes
- ##assert issubclass(type(b), bytes)
if len(self._write_buf) > self.buffer_size:
# We're full, so let's pre-flush the buffer
try:
@@ -672,6 +674,7 @@
overage = len(self._write_buf) - self.max_buffer_size
self._write_buf = self._write_buf[:self.max_buffer_size]
raise BlockingIOError(e.errno, e.strerror, overage)
+ return len(b)
def flush(self):
written = 0