No struct.pack exception for some out of range integers

[moese]

BPO	1229380
Nosy	@birkenfeld, @etrepum
Files	struct-unsignedlong.diff

^{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 = 'https://github.com/etrepum'
closed_at = <Date 2006-05-26.13:16:46.000>
created_at = <Date 2005-06-28.23:30:21.000>
labels = ['library']
title = 'No struct.pack exception for some out of range integers'
updated_at = <Date 2006-05-26.13:16:46.000>
user = 'https://bugs.python.org/moese'

bugs.python.org fields:

activity = <Date 2006-05-26.13:16:46.000>
actor = 'bob.ippolito'
assignee = 'bob.ippolito'
closed = True
closed_date = None
closer = None
components = ['Library (Lib)']
creation = <Date 2005-06-28.23:30:21.000>
creator = 'moese'
dependencies = []
files = ['1730']
hgrepos = []
issue_num = 1229380
keywords = []
message_count = 5.0
messages = ['25667', '25668', '25669', '25670', '25671']
nosy_count = 4.0
nosy_names = ['georg.brandl', 'isandler', 'bob.ippolito', 'moese']
pr_nums = []
priority = 'normal'
resolution = 'fixed'
stage = None
status = 'closed'
superseder = None
type = None
url = 'https://bugs.python.org/issue1229380'
versions = ['Python 2.4']

[moese]

struct.pack("B", -1) generates an OverflowError
exception since the B format corresponds to the
"unsigned char" type which can have values between 0
and 255.

But struct.pack("I", -1) and struct.pack("L", -1) do
not generate these errors, even if struct.pack("I",
-1L) and struct.pack("L", -1L) do (notice the final L).

[birkenfeld]

Logged In: YES
user_id=849994

Attaching patch, raises struct.error. Neal, please look over it.

Note that I find struct's error handling confusing: it's not
clear from the docs in which cases OverflowError is raised,
and in which struct.error.

[isandler]

Logged In: YES
user_id=971153

Also it appears that there is some kind of interference
between range checking and byte-order chars:

  import struct; struct.pack("H", 70000)  #Exception

  import struct; struct.pack(">H", 70000) # no exception

[birkenfeld]

Logged In: YES
user_id=849994

Assigning to Bob since he rewrote/extended the struct module
for 2.5.

[etrepum]

Logged In: YES
user_id=139309

The test suite now covers this issue and it's fixed in revision 46320.

Note that this is definitely a backwards incompatible change and we might have
to change it to a warning or something stupid like that.