ipython complaining about readline

When I install ipython on my osx and run it, I get the following warning:

 /Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/
 site-packages/IPython/utils/rlineimpl.py:96:
 RuntimeWarning: Leopard libedit detected - readline will not be wel
 behaved including some crashes on tab completion, and incorrect
 history navigation. It is highly recommended that you install
 readline, which is easy_installable with: 'easy_install readline'

I have have installed readline, and do not use the system python that was originally installed in /Library/Frameworks/Python.framework/Versions/2.7/bin/python$. The /usr/bin/python points to version 2.7 as shown below

uname -a
Darwin macbook.local 10.8.0 Darwin Kernel Version 10.8.0: Tue Jun  7 
16:33:36 PDT 2011; root:xnu-1504.15.3~1/RELEASE_I386 i386

$sudo pip install readline ipython

$ipython --version
0.11

$/usr/bin/python --version # 
Python 2.7.1 

$which python
/Library/Frameworks/Python.framewor开发者_开发知识库k/Versions/2.7/bin/python

I have read the question in Python sys.path modification not working - I added /Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages/readline-6.2.1-py2.7.egg-info to the /Library/Frameworks/Python.framework/Versions/2.7/bin/ipython so that it now looks like this: http://pastebin.com/raw.php?i=dVnxufbS

but I cannot figure out why I am getting the following error:

File
"/Library/Frameworks/Python.framework/Versions/2.7/bin/ipython",
line 9
sys.path.insert(0,"/Library/Frameworks/Python.framework/Versions/2.7/lib/
python2.7/site-packages/readline-6.2.1-py2.7.egg-info")

I do not think the above path is an issue, and my goal is to get ipython to working without complaining about readline even though it is installed and imports correctly.

When pip installs readline, it will never be imported, because readline.so goes in site-packages, which ends up behind the libedit System one, located in lib-dynload (OSX Python path order is very odd). easy_install -a readline will actually install usable readline.

So you can either use easy_install, or use pip and muck about with your PYTHONPATH/sys.path (which essentially means: DO NOT USE PIP).

A bit more detail on the IPython list (though there really isn't anything IPython-specific about this issue): http://mail.scipy.org/pipermail/ipython-user/2011-September/008426.html

EDIT: extra note about virtualenv.

There is a bug in virtualenv < 1.8.3, where readline would not be properly staged when you create an env.

If you don't mind mucking around with your PYTHONPATH, here's how you can get rid of that pesky warning:

# move site-packages to the front of your sys.path
import sys
for i in range(len(sys.path)):
    if sys.path[i].endswith('site-packages'):
        path = sys.path.pop(i)
        sys.path.insert(0, path)
        break

If you're using Django, you can put this in the ipython method of your site-packages/django/core/management/commands/shell.py so that it runs when you run ./manage.py shell.

Additional note to future readers of this answer.

In my case -- running a MacPorts installation of IPython -- there were several versions of easy_install in /opt/local/bin/, but no non-versioned symlink pointing to the most current. Performing easy_install-2.7 -a readline worked.

I am also using brew installed ipython and I had a similar issue.

⚡ easy_install-3.7 -a readline
Searching for readline
Reading https://pypi.org/simple/readline/
Download error on https://pypi.org/simple/readline/: unknown url type: https -- Some packages may not be found!
Couldn't find index page for 'readline' (maybe misspelled?)
Scanning index of all packages (this may take a while)
Reading https://pypi.org/simple/
Download error on https://pypi.org/simple/: unknown url type: https -- Some packages may not be found!
No local packages or working download links found for readline
error: Could not find suitable distribution for Requirement.parse('readline') (--always-copy skips system and development eggs)

Solution:

⚡ brew install readline
Updating Homebrew...
Warning: readline 7.0.5 is already installed, it's just not linked
You can use `brew link readline` to link this version.
⚡ brew link readline
Warning: readline is keg-only and must be linked with --force
⚡ brew link readline --force
Linking /usr/local/Cellar/readline/7.0.5... 16 symlinks created

Result:

⚡ ipython
Python 3.7.2 (default, Dec 27 2018, 07:35:06)
Type 'copyright', 'credits' or 'license' for more information
IPython 7.2.0 -- An enhanced Interactive Python. Type '?' for help.
>>> ~/.pyrc loaded successfully