fix failing ipython test in tests/cmdline

[jhpalmieri]

The test

        sage: (out, err, ret) = test_executable(["sage", "--ipython"], "\n3**33\n")
        sage: out.find("5559060566555523") >= 0
        True

fails if people have installed a newer version (0.12?) of ipython which leaves incompatible files in ~/ipython/. We might consider setting IPYTHONDIR to $DOT_SAGE/ipython/ in sage-env, but the simplest fix seems to be to do this right before running the test.

Test this by running sage --ipython to create config files in ~/ipython/. Then edit ~/ipython/ipy_user_conf.py to (for example) make it invalid Python, so it prints an error when you start sage --ipython. Then doctest the file cmdline.py before and after applying the patch.

[jason]

So this ticket depends on #12719, right?

[jason]

Oh, wait; rereading your description makes it seem like the problem is if they have a system 0.12, but Sage's 0.10, that causes a problem.

So installing #12719 won't solve the problem by itself, since modifying the global config file to be invalid python still would cause problems. However, perhaps the IPython config directory should be set to a temporary directory that can be deleted after the doctest is run? That would fulfill the ideal that doctests don't leave files laying around.

[jhpalmieri]

The doctest shouldn't leave any extra files lying around: on startup, Sage should create DOT_SAGE/ipython/ (if it doesn't exist already) and populate it with various files. From the main sage script (SAGE_ROOT/spkg/bin/sage):

    IPYTHONDIR="$DOT_SAGE/ipython" && export IPYTHONDIR
    IPYTHONRC="ipythonrc" && export IPYTHONRC
    if [ ! -d "$IPYTHONDIR" ]; then
        mkdir -p "$DOT_SAGE"
        cp -r "$SAGE_ROOT/ipython" "$DOT_SAGE/"
    fi

Running the doctest shouldn't create anything new, just use the already-present config files.

[kini]

Oops, I didn't realize this hadn't been reviewed! The code is obviously correct. Positive review from me.

[jdemeyer]

Why not do this in sage-env? That would seem a lot more logical to me.

[jhpalmieri]

I think if you run sage --ipython, it should not use the files in DOT_SAGE/ipython; otherwise, the default IPython prompt becomes sage:, for example.

[kini]

I agree with John, for what it's worth.

[jdemeyer]

Replying to jhpalmieri:

I think if you run sage --ipython, it should not use the files in DOT_SAGE/ipython; otherwise, the default IPython prompt becomes sage:, for example.

Cool. In this case, what you did is the right thing.

[jdemeyer]

Why can't I directly change status from needs_info to positive_review? I always find this so annoying.