[Zope-dev] Parameter referencing bug in Python Scripts?

[Brian Brinegar]

Hmmm,

There seems to be a bug in the way parameters are referenced in python 
scripts. I have a simple script that has a list as a default parameter. 
The script then appends something to this list and returns the list. 
Each time I call the script the list gets to be one element longer. Here 
is an example script:

## Script (Python) "pyFix"
##bind container=container
##bind context=context
##bind namespace=
##bind script=script
##bind subpath=traverse_subpath
##parameters=a=['a']
##title=
##
a.append('b')
return a

The output from the script is as follows:
1st call: ['a','b']
2nd call: ['a','b','b']
3rd call: ['a','b','b','b']
4th call: ['a','b','b','b','b']
etc.

It seems that I'm getting a reference to the default parameter which I 
then modify for future calls. Currently I'm getting around this by 
having list parameters default to none and then setting the defaults 
within the script.

I have some security concerns since I can change the default parameters 
for other users on the server. Or so it seems.

Suggestions?

Brian Brinegar
Engineering Computer Network
Purdue University