zipfile suprising "except DeprecationWarning:" block

[vstinner]

BPO	39356
Nosy	@vstinner
PRs	bpo-39356, zipfile: Remove code handling DeprecationWarning #18027

^{Note: these values reflect the state of the issue at the time it was migrated and might not reflect the current state.}

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GitHub fields:

assignee = None
closed_at = <Date 2020-01-17.14:18:29.944>
created_at = <Date 2020-01-16.09:38:13.243>
labels = ['library', '3.9']
title = 'zipfile suprising "except DeprecationWarning:" block'
updated_at = <Date 2020-01-17.14:18:29.943>
user = 'https://github.com/vstinner'

bugs.python.org fields:

activity = <Date 2020-01-17.14:18:29.943>
actor = 'vstinner'
assignee = 'none'
closed = True
closed_date = <Date 2020-01-17.14:18:29.944>
closer = 'vstinner'
components = ['Library (Lib)']
creation = <Date 2020-01-16.09:38:13.243>
creator = 'vstinner'
dependencies = []
files = []
hgrepos = []
issue_num = 39356
keywords = ['patch']
message_count = 2.0
messages = ['360107', '360193']
nosy_count = 1.0
nosy_names = ['vstinner']
pr_nums = ['18027']
priority = 'normal'
resolution = 'fixed'
stage = 'resolved'
status = 'closed'
superseder = None
type = None
url = 'https://bugs.python.org/issue39356'
versions = ['Python 3.9']

[vstinner]

Lib/zipfile.py contains the following code:

try:
filename, flag_bits = zinfo._encodeFilenameFlags()
centdir = struct.pack(structCentralDir,
stringCentralDir, create_version,
zinfo.create_system, extract_version, zinfo.reserved,
flag_bits, zinfo.compress_type, dostime, dosdate,
zinfo.CRC, compress_size, file_size,
len(filename), len(extra_data), len(zinfo.comment),
0, zinfo.internal_attr, zinfo.external_attr,
header_offset)
except DeprecationWarning:
print((structCentralDir, stringCentralDir, create_version,
zinfo.create_system, extract_version, zinfo.reserved,
zinfo.flag_bits, zinfo.compress_type, dostime, dosdate,
zinfo.CRC, compress_size, file_size,
len(zinfo.filename), len(extra_data), len(zinfo.comment),
0, zinfo.internal_attr, zinfo.external_attr,
header_offset), file=sys.stderr)
raise

It is not considered as good programmating method to put print() statement in production code: usually, it's only used for debugging :-)

The "except DeprecationWarning:" with its print has been added 12 years ago by:

commit bf02e3b
Author: Gregory P. Smith <greg@mad-scientist.com>
Date: Wed Mar 19 03:14:41 2008 +0000

Fix the struct module DeprecationWarnings that zipfile was triggering by
removing all use of signed struct values.

test_zipfile and test_zipfile64 pass.  no more warnings.

But I don't recall any complain about a DeprecationWarning on struct.pack() in zipfile.

I propose attached PR to remove it.

[vstinner]

New changeset 1d3b0aa by Victor Stinner in branch 'master':
bpo-39356, zipfile: Remove code handling DeprecationWarning (GH-18027)
1d3b0aa