On Windows it's the directory that contains the zip file or directory with __main__.py, not the current directory. This seems normal to me. The directory or zip file is effectively executing as a script. I can understand wanting more isolated behavior in this case, i.e. make isolated mode the default when executing a directory or zip file as a script.
C:\>py -3.5 C:\Temp\spam
__file__:
C:\Temp\spam\__main__.py
sys.path:
C:\Temp\spam
C:\Temp
C:\Program Files\Python35\python35.zip
C:\Program Files\Python35\DLLs
C:\Program Files\Python35\lib
C:\Program Files\Python35
C:\Program Files\Python35\lib\site-packages
C:\>py -3.5 C:\Temp\spam.zip
__file__:
C:\Temp\spam.zip\__main__.py
sys.path:
C:\Temp\spam.zip
C:\Temp
C:\Program Files\Python35\python35.zip
C:\Program Files\Python35\DLLs
C:\Program Files\Python35\lib
C:\Program Files\Python35
C:\Program Files\Python35\lib\site-packages |