The Sane documentation seems to imply that these option strings contain
Latin-1 text, not byte data, so we decode it and present it to the user
that way.
The EPS encoder wasn't part of Gohlke's test suite, so the previous "fixes"
there were only expected syntactic ones. This gives a cleaner fix to the
encoder.
The decoder doesn't work in round-trip due to a missing eps_decoder method
on the core module, but it's clear it worked at some point.
This is Gohlke's fix for two issues: negative indexes on paths were not
resolved to the correct index, and path slicing didn't work.
His fix for slicing is related to the one found at:
http://renesd.blogspot.com/2009/07/python3-c-api-simple-slicing-sqslice.html
With this commit, all 79 tests (82 minus the three skipped ones) run
successfully on Python 2.6.8, Python 2.7.3rc2, and Python 3.2.3.
There are two main issues fixed with this commit:
* bytes vs. str: All file, image, and palette data are now handled as
bytes. A new _binary module consolidates the hacks needed to do this
across Python versions. tostring/fromstring methods have been renamed to
tobytes/frombytes, but the Python 2.6/2.7 versions alias them to the old
names for compatibility. Users should move to tobytes/frombytes.
One other potentially-breaking change is that text data in image files
(such as tags, comments) are now explicitly handled with a specific
character encoding in mind. This works well with the Unicode str in
Python 3, but may trip up old code expecting a straight byte-for-byte
translation to a Python string. This also required a change to Gohlke's
tags tests (in Tests/test_file_png.py) to expect Unicode strings from
the code.
* True div vs. floor div: Many division operations used the "/" operator
to do floor division, which is now the "//" operator in Python 3. These
were fixed.
As of this commit, on the first pass, I have one failing test (improper
handling of a slice object in a C module, test_imagepath.py) in Python 3,
and three that that I haven't tried running yet (test_imagegl,
test_imagegrab, and test_imageqt). I also haven't tested anything on
Windows. All but the three skipped tests run flawlessly against Pythons
2.6 and 2.7.
