tasks.py path lookup bug with virtualenv and pip dependency on github project

[zheller]

Hey,

I was using invoke in a project, which had another project as a dependency that was installed via pip's -e flag from a github repository at a specific hash. This dependency also uses invoke and had a tasks.py file.

What happened was that invoke traversed the directory tree backwords and ended up using the tasks.py file in my virtualenv. What happens internally as far as I can tell is pip downloads the repos source in .virtualenv/src and then runs python setup.py develop in order to install it. The tasks.py file in my virtualenv/src directory from my depenedency ended up taking precedence over the tasks.py file in my project repository's top level directory, despite using the -r flag and setting the project root.

For reference, I use virtualenvwrapper and the directory structure looks something like this

~/src/.virtualenvs/<env-name>/src/
~/src/my-project

[Ivoz]

In a python shell could you run

>>> import sys
>>> print(sys.path)
>>> from invoke.loader import Loader
>>> Loader().load_collection()
>>> print(sys.path)

and show the results of your sys.path before and after?

[bitprophet]

Let's consider this part of the discussion going on in #92. Thank for the report! Will try to get your use case sorted somehow :)

Also - would be great to get answers to what @Ivoz said so we can make sure we understand the situation correctly.