I want to add all folders in my Pydev project to PYTHONPATH so that I can reap the benefits of easily seeing unused imports etc. To do this I seemingly have to add all folde
Ok, just to give a proper answer, you should just add the folder(s) that you want to be in the PYTHONPATH as your source folder(s).
So, if you have a structure such as
/myproject
/myproject/src
/myproject/package
/myproject/package/__init__.py
/myproject/package2
/myproject/package2/__init__.py
You'd only want to add /myproject/src as your PYTHONPATH.
If you really had multiple folders to add there, you could edit the .pydevproject file (which is at the root of your project) and add multiple folders there at once (although as noted, you should only have few folders there, so, this is generally not needed -- although sometimes you may want that if you're adding multiple libraries to a folder or something alike).
The PyDev FAQ explains this properly on the items listed below:
How do I import existing projects/sources into PyDev?
How do I import existing projects/sources for a Django project into PyDev?