[Python-checkins] gh-47061: Deprecate `chunk` (GH-91419)
brettcannon
webhook-mailer at python.org
Mon Apr 11 18:02:45 EDT 2022
https://github.com/python/cpython/commit/3869a839d5f14a91978c6158a03c68fac5e938dd
commit: 3869a839d5f14a91978c6158a03c68fac5e938dd
branch: main
author: Brett Cannon <brett at python.org>
committer: brettcannon <brett at python.org>
date: 2022-04-11T15:02:41-07:00
summary:
gh-47061: Deprecate `chunk` (GH-91419)
files:
A Misc/NEWS.d/next/Library/2022-04-10-11-11-33.gh-issue-91217.K82AuH.rst
M Doc/whatsnew/3.11.rst
M Lib/aifc.py
M Lib/chunk.py
M Lib/wave.py
diff --git a/Doc/whatsnew/3.11.rst b/Doc/whatsnew/3.11.rst
index df0b0a7fbebec..cc358b4ffdb2a 100644
--- a/Doc/whatsnew/3.11.rst
+++ b/Doc/whatsnew/3.11.rst
@@ -850,6 +850,7 @@ Deprecated
* :mod:`audioop`
* :mod:`cgi`
* :mod:`cgitb`
+ * :mod:`chunk`
(Contributed by Brett Cannon in :issue:`47061`.)
diff --git a/Lib/aifc.py b/Lib/aifc.py
index 314cfd230d6cb..5254987e22bc1 100644
--- a/Lib/aifc.py
+++ b/Lib/aifc.py
@@ -255,7 +255,9 @@ def _write_float(f, x):
_write_ulong(f, himant)
_write_ulong(f, lomant)
-from chunk import Chunk
+with warnings.catch_warnings():
+ warnings.simplefilter("ignore", DeprecationWarning)
+ from chunk import Chunk
from collections import namedtuple
_aifc_params = namedtuple('_aifc_params',
diff --git a/Lib/chunk.py b/Lib/chunk.py
index 870c39fe7f503..618781efd11e7 100644
--- a/Lib/chunk.py
+++ b/Lib/chunk.py
@@ -48,6 +48,10 @@
default is 1, i.e. aligned.
"""
+import warnings
+
+warnings._deprecated(__name__, remove=(3, 13))
+
class Chunk:
def __init__(self, file, align=True, bigendian=True, inclheader=False):
import struct
diff --git a/Lib/wave.py b/Lib/wave.py
index 47a233df0a3ab..9a4557487b6e6 100644
--- a/Lib/wave.py
+++ b/Lib/wave.py
@@ -71,7 +71,6 @@
is destroyed.
"""
-from chunk import Chunk
from collections import namedtuple
import builtins
import struct
@@ -100,6 +99,119 @@ def _byteswap(data, width):
return bytes(swapped_data)
+class _Chunk:
+ def __init__(self, file, align=True, bigendian=True, inclheader=False):
+ import struct
+ self.closed = False
+ self.align = align # whether to align to word (2-byte) boundaries
+ if bigendian:
+ strflag = '>'
+ else:
+ strflag = '<'
+ self.file = file
+ self.chunkname = file.read(4)
+ if len(self.chunkname) < 4:
+ raise EOFError
+ try:
+ self.chunksize = struct.unpack_from(strflag+'L', file.read(4))[0]
+ except struct.error:
+ raise EOFError from None
+ if inclheader:
+ self.chunksize = self.chunksize - 8 # subtract header
+ self.size_read = 0
+ try:
+ self.offset = self.file.tell()
+ except (AttributeError, OSError):
+ self.seekable = False
+ else:
+ self.seekable = True
+
+ def getname(self):
+ """Return the name (ID) of the current chunk."""
+ return self.chunkname
+
+ def close(self):
+ if not self.closed:
+ try:
+ self.skip()
+ finally:
+ self.closed = True
+
+ def seek(self, pos, whence=0):
+ """Seek to specified position into the chunk.
+ Default position is 0 (start of chunk).
+ If the file is not seekable, this will result in an error.
+ """
+
+ if self.closed:
+ raise ValueError("I/O operation on closed file")
+ if not self.seekable:
+ raise OSError("cannot seek")
+ if whence == 1:
+ pos = pos + self.size_read
+ elif whence == 2:
+ pos = pos + self.chunksize
+ if pos < 0 or pos > self.chunksize:
+ raise RuntimeError
+ self.file.seek(self.offset + pos, 0)
+ self.size_read = pos
+
+ def tell(self):
+ if self.closed:
+ raise ValueError("I/O operation on closed file")
+ return self.size_read
+
+ def read(self, size=-1):
+ """Read at most size bytes from the chunk.
+ If size is omitted or negative, read until the end
+ of the chunk.
+ """
+
+ if self.closed:
+ raise ValueError("I/O operation on closed file")
+ if self.size_read >= self.chunksize:
+ return b''
+ if size < 0:
+ size = self.chunksize - self.size_read
+ if size > self.chunksize - self.size_read:
+ size = self.chunksize - self.size_read
+ data = self.file.read(size)
+ self.size_read = self.size_read + len(data)
+ if self.size_read == self.chunksize and \
+ self.align and \
+ (self.chunksize & 1):
+ dummy = self.file.read(1)
+ self.size_read = self.size_read + len(dummy)
+ return data
+
+ def skip(self):
+ """Skip the rest of the chunk.
+ If you are not interested in the contents of the chunk,
+ this method should be called so that the file points to
+ the start of the next chunk.
+ """
+
+ if self.closed:
+ raise ValueError("I/O operation on closed file")
+ if self.seekable:
+ try:
+ n = self.chunksize - self.size_read
+ # maybe fix alignment
+ if self.align and (self.chunksize & 1):
+ n = n + 1
+ self.file.seek(n, 1)
+ self.size_read = self.size_read + n
+ return
+ except OSError:
+ pass
+ while self.size_read < self.chunksize:
+ n = min(8192, self.chunksize - self.size_read)
+ dummy = self.read(n)
+ if not dummy:
+ raise EOFError
+
+
+
class Wave_read:
"""Variables used in this class:
@@ -134,7 +246,7 @@ class Wave_read:
def initfp(self, file):
self._convert = None
self._soundpos = 0
- self._file = Chunk(file, bigendian = 0)
+ self._file = _Chunk(file, bigendian = 0)
if self._file.getname() != b'RIFF':
raise Error('file does not start with RIFF id')
if self._file.read(4) != b'WAVE':
@@ -144,7 +256,7 @@ def initfp(self, file):
while 1:
self._data_seek_needed = 1
try:
- chunk = Chunk(self._file, bigendian = 0)
+ chunk = _Chunk(self._file, bigendian = 0)
except EOFError:
break
chunkname = chunk.getname()
diff --git a/Misc/NEWS.d/next/Library/2022-04-10-11-11-33.gh-issue-91217.K82AuH.rst b/Misc/NEWS.d/next/Library/2022-04-10-11-11-33.gh-issue-91217.K82AuH.rst
new file mode 100644
index 0000000000000..0181bbcce9cd8
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2022-04-10-11-11-33.gh-issue-91217.K82AuH.rst
@@ -0,0 +1 @@
+Deprecate the chunk module.
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