Added support for encoding and decoding iTXt chunks.

[dolda2000]

No description provided.

[coveralls]

Changes Unknown when pulling c469dd9 on dolda2000:itxt into * on python-pillow:master*.

[hugovk]

@dolda2000 Please could you also add tests for this code? Thanks!

[dolda2000]

@hugovk Not sure. When I run "setup.py test", it gives me an error:

Traceback (most recent call last):
  File "setup.py", line 753, in <module>
    zip_safe=True,
  File "/usr/lib/python3.2/distutils/core.py", line 148, in setup
    dist.run_commands()
  File "/usr/lib/python3.2/distutils/dist.py", line 917, in run_commands
    self.run_command(cmd)
  File "/usr/lib/python3.2/distutils/dist.py", line 936, in run_command
    cmd_obj.run()
  File "/usr/lib/python3/dist-packages/setuptools/command/test.py", line 137, in run
    self.with_project_on_sys_path(self.run_tests)
  File "/usr/lib/python3/dist-packages/setuptools/command/test.py", line 117, in     with_project_on_sys_path
    func()
  File "/usr/lib/python3/dist-packages/setuptools/command/test.py", line 146, in run_tests
    testLoader = loader_class()
  File "/usr/lib/python3.2/unittest/main.py", line 123, in __init__
    self.parseArgs(argv)
  File "/usr/lib/python3.2/unittest/main.py", line 191, in parseArgs
    self.createTests()
  File "/usr/lib/python3.2/unittest/main.py", line 198, in createTests
    self.module)
  File "/usr/lib/python3.2/unittest/loader.py", line 137, in loadTestsFromNames
    suites = [self.loadTestsFromName(name, module) for name in names]
  File "/usr/lib/python3.2/unittest/loader.py", line 137, in <listcomp>
    suites = [self.loadTestsFromName(name, module) for name in names]
  File "/usr/lib/python3.2/unittest/loader.py", line 105, in loadTestsFromName
    parent, obj = obj, getattr(obj, part)
AttributeError: 'module' object has no attribute 'tests'

Is this not how one is supposed to run tests on PIL? I will admit I have no experience with Python's testing framework.

[hugovk]

@dolda2000 You can run them all like this (taken from .travis.yml):

nosetests -vx Tests/test_*.py

Or with coverage:

coverage run --append --

include=PIL/* -m nose -vx Tests/test_*.py

Or to run just a single test:

python Tests/test_sometest.py

Either edit an appropriate existing test file or create a new one if you wish; helper.py has a base test class with helper functions. Test images go in Tests/images/.

[dolda2000]

Thanks.

I added some tests. Is that something you would be happy with?

[coveralls]

Changes Unknown when pulling 2b4d91e on dolda2000:itxt into * on python-pillow:master*.

[hugovk]

@dolda2000 Yes, that looks the right sort of thing. Please can you also test the new add_itxt() and the iTxt part of add_text()?

[dolda2000]

Ah, right, of course. Fixed.

I also took the opportunity to do it so that Unicode strings with non-Latin1 characters in them are always encoded as iTXt chunks, in order to actually preserve their contents.

[coveralls]

Changes Unknown when pulling 2687b5c on dolda2000:itxt into * on python-pillow:master*.

[hugovk]

This function uses a lot of single-letter variable names and it's not always clear what they do. Please could you use more descriptive names?

[dolda2000]

To be fair, I was trying to keep in style with the surrounding chunk_tEXt and chunk_zTXt functions. :)

Since they use similar variable naming, I don't quite see what would be better.

[hugovk]

Thanks for the contribution!