Use os.path.dirname() not os.path.join(foo, '..')

[Thomas Güttler <hv@…>]

If you use symlinks to directories using ".." will lead you
to the wrong directory.

Here is an example:

mkdir -p /tmp/dotdot/two
ln -s  /tmp/dotdot/two/ /tmp/symlink
cd /tmp/symlink
ls ..
 --> two
 Content of /tmp/symlink, not /tmp!

[Gary Wilson]

fixed ticket formatting

[Gary Wilson]

Using dirname() returns the same thing as what's currently there if there is no trailing slash:

>>> directory = os.getcwd()
>>> directory
'/tmp/dotdot/two'
>>> project_dir = os.path.normpath(os.path.join(directory, '..'))
>>> project_dir
'/tmp/dotdot'
>>> parent_dir = os.path.basename(project_dir)
>>> parent_dir
'dotdot'

and

>>> directory = os.getcwd()
>>> directory
'/tmp/dotdot/two'
>>> project_dir = os.path.normpath(os.path.dirname(directory))
>>> project_dir
'/tmp/dotdot'
>>> parent_dir = os.path.basename(project_dir)
>>> parent_dir
'dotdot'

However, using dirname() returns different results if directory ends with a slash:

>>> directory = '/tmp/dotdot/two/'
>>> project_dir = os.path.normpath(os.path.join(directory, '..'))
>>> project_dir
'/tmp/dotdot'
>>> parent_dir = os.path.basename(project_dir)
>>> parent_dir
'dotdot'

and

>>> directory = '/tmp/dotdot/two/'
>>> project_dir = os.path.normpath(os.path.dirname(directory))
>>> project_dir
'/tmp/dotdot/two'
>>> parent_dir = os.path.basename(project_dir)
>>> parent_dir
'two'

[Gary Wilson]

So I'm not seeing how the using of '..' is leading to different results as you have mentioned. However, I do believe we should at least be using os.pardir there instead of '..'.

[Gary Wilson]

(In [6456]) Refs #5690 -- Changed path joining to use os.pardir instead of '..'.

[Thomas Guettler (Home)]

In django/core/management/init.py normpath() is not used. Please add it. This would
fix my problem:

[Malcolm Tredinnick]

Replying to Thomas Guettler (Home):

In django/core/management/init.py normpath() is not used. Please add it. This would
fix my problem:

We aren't going to add anything without an explanation of what the real problem is. Gary has already mentioned that he doesn't see what would be causing the problem here. Please give an explanation of what you are trying to fix so that we can ensure we make the correct fix.

[Thomas Güttler <hv@…>]

My problem was, that the import failed, because the directory was a symlink.
I changed my setup and can't reproduce the problem. Using ".." (without
normpath) is a bad way to get the upper directory, since it can fail. See
shell example above. Nevertheless I close this ticket. Sorry for the noise.