[Python-Dev] Updating turtle.py

[Terry Reedy]

I have two areas of questions about updating turtle.py. First the module 
itself, then a turtle tracker issue versus code cleanup policies.

A. Unlike most stdlib modules, turtle is copyrighted and licensed by an 
individual.
'''
# turtle.py: a Tkinter based turtle graphics module for Python
# Version 1.1b - 4. 5. 2009
# Copyright (C) 2006 - 2010  Gregor Lingl
# email: glingl at aon.at
'''
I am not sure what the copyright covers other than the exact text 
contributed, with updates, by Gregor. It certainly does not cover the 
API and whatever code he copied from the previous version (unless that 
was also by him, and I have no idea how much he copied when 
reimplementing). I don't think it should cover additions made by others 
either. Should there be another line to cover these?
'''
# Permission is granted to anyone to use this software for any purpose,
# including commercial applications, and to alter it and redistribute it
# freely, subject to the following restrictions:
#
# 1. The origin of this software must not be misrepresented; you must not
#    claim that you wrote the original software. If you use this software
#    in a product, an acknowledgment in the product documentation would be
#    appreciated but is not required.
# 2. Altered source versions must be plainly marked as such, and must not be
#    misrepresented as being the original software.
# 3. This notice may not be removed or altered from any source distribution.
'''
As to point 2, the source has been altered a bit (by others) but it is 
not marked as such. How should it be?
'''
_ver = "turtle 1.1b- - for Python 3.1   -  4. 5. 2009"
'''
Obsolete; delete or alter (how)?

When this replaced the previous turtle.py, it was considered 'owned' by 
Gregor in that changes had to go through him. However, he became 
inactive soon after and maintenance ceased. There has been only one 
turtle-specific code change that I know of (by Ned Daily, a month ago, 
for OSX. So is turtle.py unpatchable by anyone or fair game for anyone?

A particular example: Gregor added intermediate layers to isolate turtle 
from tkinter. (He had a plan to add other backends, but I believe he 
abandoned that.) If someone wanted to reduce the layering and make the 
code easier to understand and maintain, while speeding execution, would 
that be allowed now?


B. Lets assuming that turtle.py is, at least to some degree, fair game 
for fixes and enhancements. PSF Python PyLadies (Jessica Keller, Lynn 
Root) are participating in the 2014 GNOME Outreach Program for Women 
(OPW) https://wiki.python.org/moin/OPW/2014 . One of the projects 
(bottem of that page) is Graphical Python, in particular Turtle.

A few days ago, Jessica posted
http://bugs.python.org/issue21573 Clean up turtle.py code formatting
"Lib/turtle.py has some code formatting issues. Let's clean them up to 
make the module easier to read as interns start working on it this 
summer." She want to follow cleanup with code examination, fixes, and 
enhancements.

Responding today, I cautioned that clean-up only patches, such as she 
apparently would like to start with, are not in favor. But I cannot say 
how the policy applies to her proposal. Does the 'promise' of later work 
on the code make preliminary clean-up ok?

Since she only marked the issue for 3.5, I also cautioned that 3.5-only 
cleanups would make fixing bugs in other issues harder. Is the code 
clean-up policy the same for all branches?

Test? you ask?. There are apparently no unittests for turtle. On the 
other hand, turtledemo tests the overall function of the module and of 
many (most) of the top-level turtle functions.

-- 
Terry Jan Reedy