[sugar] [PATCH] Trac #7480: Need to 'reset' the network configurations - short term fix

[Michael Stone]

On Thu, Aug 14, 2008 at 11:12:09AM -0400, Erik Garrison wrote:
>On Tue, Aug 12, 2008 at 12:02:41AM -0400, Michael Stone wrote:
>> On Mon, Aug 11, 2008 at 09:31:26PM -0400, Erik Garrison wrote:
>>> Attached is a patch which adds a 'reset network configuration' button to
>>> the network tab of the sugar control panel.
>>
>> Thanks very much for the patch, and for the thoughtful design.
>>
>>> +        n = 1 + max(map(lambda x: int(x.replace('networks.cfg.bak.', '')),
>>> +                        network_cfgs))
>>
>> This expression, while cute, is unsafe and will result in failure if you
>> ever encounter a file with a name like 'networks.cfg.bak.hi'. 
>
>The solution is to guarantee that inputs are of the correct form
>(networks.cfg.bak.\d+$).  As follows, two lines previously should be:
>
>    network_cfgs = [file
>                    for file in os.listdir('/home/olpc/.sugar/default/nm')
>                    if re.match('networks.cfg.bak.\d+$', file)]
>
>> Please write total code or handle exceptions appropriately.
>
>I don't understand what you mean by 'total' code.  

Total (as opposed to partial) functions, programs, expressions, etc. are
defined for every possible input rather than for only some of their
inputs. The way you defined network_cfgs was partial in that, in
addition to generating an exception, it also left "n" undefined (not
even set to None) for some inputs (such as those I described).

> You do not need to ask me to write bug-free code. 

There are actually lots of people (including myself) who I find I have
to ask to write bug-free code (often concerning race conditions).
However, I'm glad to hear that you care deeply about it as well.

> Please just say 'I found a problem' and update the patch.

As you prefer.

Michael