Hello! The following patch adds unit tests for the previously untested `imghdr` module.

Beside my review, I think we need one more test that tests the invalid image file, for example file with header b'cutecat'.

Thanks for the review, Vajrasky! Here's the updated version.

Hello. Here's a new version which uses real image files as testing data.

I made a simple exr file with the lib Exr (it's a half float ZIP16 RGBA file), in order to add real exr file to the unit test.
When use with the patch i made here http://bugs.python.org/issue20295 ,
this sample file return 'exr'.

Sorry, i don't know how to create an update version of your patch (i just start to use mercurial), so i just upload the sample.

In general the patch LGTM, but additional tests can be added.

Needed various tests for imghdr.what() arguments:

* First argument is bytes, int or None.
* First argument is a name of non-existent file.
* First argument is text stream.
* First argument is output stream.
* First argument is closed stream.
* First argument is non-seekable stream.
* Second argument is bytearray.
* Second argument is str.
* Second argument is None.

Try to insert test function which handles one of already supported format at the front of imghdr.test.

Hello! Here's the new version of the patch, with tests proposed by Serhiy.

Looks as you forgot to include some test files in the patch.

And these files are too large. Much smaller images would be enough. For example you can use python.org icon: http://www.python.org/favicon.ico.

Here's a smaller patch. Serhiy, what test files are missing?

Last patch contains only pbm and xbm test files, while test_imghdr expects 11 different image files: png, gif, bmp, etc.

Ah, I understand now. Maybe it is related to the fact that I used `hg diff --git`? Doing the following works for me, both Windows and FreeBsd and all the files are present afterwards:

1. hg diff --git > patch
2. hg import --no-commit patch

Although I'm not sure why it doesn't work in your case.

Oh, yes, my bad. I used the patch utility. Sorry.

New changeset b28909d501c0 by Serhiy Storchaka in branch '2.7':
Issue #19990: Added tests for the imghdr module.
http://hg.python.org/cpython/rev/b28909d501c0

New changeset fde9e9832749 by Serhiy Storchaka in branch '3.3':
Issue #19990: Added tests for the imghdr module.
http://hg.python.org/cpython/rev/fde9e9832749

New changeset 94813eab5a58 by Serhiy Storchaka in branch 'default':
Issue #19990: Added tests for the imghdr module.
http://hg.python.org/cpython/rev/94813eab5a58

Thank you Claudiu.

I have reorganized tests somewhat and added new test for file position.

New changeset e2d013e90e88 by Ned Deily in branch '2.7':
Issue #19990: Install test/imghdrdata.
http://hg.python.org/cpython/rev/e2d013e90e88

New changeset 5fbe155e62b0 by Ned Deily in branch '3.3':
Issue #19990: Install test/imghdrdata.
http://hg.python.org/cpython/rev/5fbe155e62b0

New changeset b41ba99a276c by Ned Deily in branch 'default':
Issue #19990: Install test/imghdrdata.
http://hg.python.org/cpython/rev/b41ba99a276c