loaddata fails when a directory in the fixture path contains a dot

[Alisson Silveira]

How to reproduce:

Create a fixture in a directory containing a dot, for example:

fixtures/fix.v1/data.json

Run (without specifying the file extension):

python manage.py loaddata fixtures/fix.v1/data

This raises:

CommandError: Problem installing fixture 'fixtures/fix': v1/data is not a known serialization format.

This occurs when a directory in the fixture path contains a dot, as the full path is incorrectly split on "." instead of operating on the file name.

Expected behavior: Django should correctly determine the fixture format based on the file name and load the fixture successfully, ignoring dots in directory names.

A fix has been identified and will be submitted in a pull request.