random.randrange don't return correct value for big number

[mft]

BPO	1590891
Nosy	@arigo, @rhettinger, @josiahcarlson
Files	randrange1.diff: Proposed fix

^{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/rhettinger'
closed_at = <Date 2006-12-20.06:43:10.000>
created_at = <Date 2006-11-05.16:54:05.000>
labels = ['library']
title = "random.randrange don't return correct value for big number"
updated_at = <Date 2006-12-20.06:43:10.000>
user = 'https://bugs.python.org/mft'

bugs.python.org fields:

activity = <Date 2006-12-20.06:43:10.000>
actor = 'rhettinger'
assignee = 'rhettinger'
closed = True
closed_date = None
closer = None
components = ['Library (Lib)']
creation = <Date 2006-11-05.16:54:05.000>
creator = 'mft'
dependencies = []
files = ['2207']
hgrepos = []
issue_num = 1590891
keywords = []
message_count = 4.0
messages = ['30457', '30458', '30459', '30460']
nosy_count = 4.0
nosy_names = ['arigo', 'rhettinger', 'josiahcarlson', 'mft']
pr_nums = []
priority = 'normal'
resolution = 'fixed'
stage = None
status = 'closed'
superseder = None
type = None
url = 'https://bugs.python.org/issue1590891'
versions = []

[mft]

Python 2.4.3 (#1, Oct  3 2006, 00:36:06)
[GCC 4.1.1 (Gentoo 4.1.1-r1)] on linux2
Type "help", "copyright", "credits" or "license" for
more information.
>>> import random
>>> random.randrange(1000000000000,
-100000000000000000000, -200)
267471051174796896L

Obviously, the result is not in the specified range;
1000000000000 < 267471051174796896,
-100000000000000000000 < 267471051174796896
and
(267471051174796896 - 1000000000000) % (-200) != 0.

I'm using 2.3.5 and 2.4.3, and their behaviors are
identical.
I haven't checked about 2.5.

[josiahcarlson]

Logged In: YES
user_id=341410

2.5 has the same behavior.

One workaround (until it gets fixed) is to do the following...

def myrandrange(start, stop, step):
    return start + random.randrange((stop-start)//step)*step

random.randrange should change to do some variant of the
above, given sane start, stop, step arguments.

[arigo]

Logged In: YES
user_id=4771

Oups. If the interval is very large, the step is
ignored. Patch attached...

[rhettinger]

Thanks for the report.

Fixed in revision 53099.