setup.py failure on Python 3

[takluyver]

#3340 causes more of the codebase to be imported from setup.py. Anything that's imported at that stage must be valid Python 3 syntax, because 2to3 hasn't run at that point.

Specifically, it now tries to load IPython.utils.path, which pulls in the config system, more of utils, pexpect, etc. and IPython.frontend.html.notebook, which is probably going to bring in most of the rest of the codebase.

Unless we're going to bite the bullet and do a full source port straight away, we need a better way to determine whether setup.py is running for a package manager.

Traceback (most recent call last):
  File "setup.py", line 145, in <module>
    require_clean_submodules()
  File "setup.py", line 129, in require_clean_submodules
    status = check_submodule_status(here)
  File "IPython/utils/submodule.py", line 64, in check_submodule_status
    if is_package():
  File "IPython/utils/submodule.py", line 46, in is_package
    from IPython.utils.path import get_ipython_package_dir
  File "/home/slave/jenkins/workspace/ipython-multi/91fd20c6/IPython/__init__.py", line 43, in <module>
    from .config.loader import Config
  File "/home/slave/jenkins/workspace/ipython-multi/91fd20c6/IPython/config/__init__.py", line 16, in <module>
    from .application import *
  File "/home/slave/jenkins/workspace/ipython-multi/91fd20c6/IPython/config/application.py", line 283
    print os.linesep.join(lines)
           ^
SyntaxError: invalid syntax

[takluyver]

Note: this showed up on Travis as an 'error', not a failure. We need to remember to pay attention to those: if Travis gives anything but a green light, we need to at least briefly look into it.

[pleabargain]

Getting a slightly diff. error but python3 install is failing:
python3 setup.py install

Traceback (most recent call last):
  File "setup.py", line 145, in <module>
    require_clean_submodules()
  File "setup.py", line 129, in require_clean_submodules
    status = check_submodule_status(here)
  File "IPython/utils/submodule.py", line 64, in check_submodule_status
    if is_package():
  File "IPython/utils/submodule.py", line 46, in is_package
    from IPython.utils.path import get_ipython_package_dir
  File "/usr/local/src/ipython/IPython/__init__.py", line 43, in <module>
    from .config.loader import Config
  File "/usr/local/src/ipython/IPython/config/__init__.py", line 16, in <module>
    from .application import *
  File "/usr/local/src/ipython/IPython/config/application.py", line 124
    name = Unicode(u'application')
                                ^
SyntaxError: invalid syntax

[takluyver]

The difference in the error is just down to the Python version - the error I pasted is from 3.3, yours is from 3.2 (or potentially even an earlier version).

[pleabargain]

python3 --version
Python 3.2.3

[parinyahi]

Got this error during installation

"C:\Python27>python D:\ipython-2.1.0\setup.py install

Traceback (most recent call last):
File "D:\ipython-2.1.0\setup.py", line 56, in
from setupbase import target_update
File "D:\ipython-2.1.0\setupbase.py", line 504, in
execfile(pjoin('IPython','utils','submodule.py'), globals())
IOError: [Errno 2] No such file or directory: 'IPython\utils\submodule.py'"

[takluyver]

@parinyahi that's a different issue, so please file it separately, or use the chat room or email list to ask about it. It looks like setup.py assumes it's running from the working directory. I don't know if we'd be interested in changing that or not.