Travis Broken - Attrs install

[ghost]

Latest Travis runs are broken because of a weird attrs install issue.

The latest version of jsonschema clearly specifies attrs>=17.4.0 https://github.com/Julian/jsonschema/blob/master/setup.cfg

In our Travis setup, we run pip install -r requirements_dev.txt - that specifies -e ., ie setup.py and that specifes jsonschema.

So I would assume that when pip was run, it would be smart enought to work out it needs attrs>=17.4.0.

But No.

It says Requirement already satisfied: attrs>=17.2.0 in /home/travis/virtualenv/python3.6.3/lib/python3.6/site-packages (from pytest->-r requirements_dev.txt (line 4))

And if you stick a pip freeze in it says the current version of attrs is 17.3.0

And then, not surprisingly, pytest crashes in a Jsonschema import TypeError: attrib() got an unexpected keyword argument 'converter'

Why, isn't pip getting a later version of attrs? The (line 4)) is a clue - that line is the pytest line, not the -e . line. Also, it works fine on Python 3.5 (gets attrs 18.1.0, all works) - it only breaks on Python 3.6

???????????????????????????

[ghost]

Call with @kindly - noted there are no req.in files - I'm going to try adding those