[Python-bugs-list] [ python-Bugs-618146 ] overflow error in calendar module

noreply@sourceforge.net noreply@sourceforge.net
Fri, 01 Nov 2002 18:53:44 -0800

Bugs item #618146, was opened at 2002-10-03 12:57
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>Category: Python Library
Group: Python 2.2.1
Status: Open
Resolution: None
Priority: 5
Submitted By: Kaleb Pederson (kibab)
Assigned to: Nobody/Anonymous (nobody)
Summary: overflow error in calendar module

Initial Comment:
The calendar module doesn't explicitly say that it 
doesn't work for dates pre-1970.  The best case is that 
this is a DOCUMENTATION BUG.  I would prefer to see 
a more powerful date module that starts at the 
beginning of the Gregorian calendar.

What it does say:

>From http://www.python.org/doc/current/lib/module-
calendar.html: (when 2.2.1 is current)

weekday(year, month, day)  - Returns the day of the 
week (0 is Monday) for year (1970-...), month (1-12), 
day (1-31).

// I figured that was fine, I can avoid using that function 
in my wrapper

timegm(tuple) - An unrelated but handy function that 
takes a time tuple such as returned by the gmtime() 
function in the time module, and returns the 
corresponding Unix timestamp value, assuming an 
epoch of 1970, and the POSIX encoding. In fact, 
time.gmtime() and timegm() are each others' inverse.

// Okay, I can avoid that too, especially since it 
is "unrelated"

I probably should have got a clue based on the above, 
but I didn't....

Here is the traceback:

(under python 2.2.1-Windows)
>>> import calendar
>>> calendar.monthcalendar(1969,12)
Traceback (most recent call last):
  File "<stdin>", line 1, in ?
  File "c:\progra~1\python22\lib\calendar.py", line 122, 
in monthcalendar
    day1, ndays = monthrange(year, month)
  File "c:\progra~1\python22\lib\calendar.py", line 115, 
in monthrange
    day1 = weekday(year, month, 1)
  File "c:\progra~1\python22\lib\calendar.py", line 106, 
in weekday
    secs = mktime((year, month, day, 0, 0, 0, 0, 0, 0))
OverflowError: mktime argument out of range

The error is identical under Linux

There was one related "bug report" previously but 
nothing else identical:
[ 434143 ] calendar module broken for 1900


>Comment By: Neal Norwitz (nnorwitz)
Date: 2002-11-01 21:53

Logged In: YES 

Is this still a problem in 2.2.2?


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