Python IPython 模块，get_ipython() 实例源码

def can_use_widgets():
    """ Expanded from from http://stackoverflow.com/a/34092072/1958900
    """
    if 'IPython' not in sys.modules:
        # IPython hasn't been imported, definitely not
        return False
    from IPython import get_ipython

    # check for `kernel` attribute on the IPython instance
    if getattr(get_ipython(), 'kernel', None) is None:
        return False

    try:
        import ipywidgets as ipy
        import traitlets
    except ImportError:
        return False

    if int(ipy.__version__.split('.')[0]) < 6:
        print('WARNING: widgets require ipywidgets 6.0 or later')
        return False

    return True

def page(data, start=0, screen_lines=0, pager_cmd=None):
    """Display content in a pager, piping through a pager after a certain length.

    data can be a mime-bundle dict, supplying multiple representations,
    keyed by mime-type, or text.

    Pager is dispatched via the `show_in_pager` IPython hook.
    If no hook is registered, `pager_page` will be used.
    """
    # Some routines may auto-compute start offsets incorrectly and pass a
    # negative value.  Offset to 0 for robustness.
    start = max(0, start)

    # first, try the hook
    ip = get_ipython()
    if ip:
        try:
            ip.hooks.show_in_pager(data, start=start, screen_lines=screen_lines)
            return
        except TryNext:
            pass

    # fallback on default pager
    return pager_page(data, start, screen_lines, pager_cmd)

def test_latex_completions():
    from IPython.core.latex_symbols import latex_symbols
    import random
    ip = get_ipython()
    # Test some random unicode symbols
    keys = random.sample(latex_symbols.keys(), 10)
    for k in keys:
        text, matches = ip.complete(k)
        nt.assert_equal(len(matches),1)
        nt.assert_equal(text, k)
        nt.assert_equal(matches[0], latex_symbols[k])
    # Test a more complex line
    text, matches = ip.complete(u'print(\\alpha')
    nt.assert_equal(text, u'\\alpha')
    nt.assert_equal(matches[0], latex_symbols['\\alpha'])
    # Test multiple matching latex symbols
    text, matches = ip.complete(u'\\al')
    nt.assert_in('\\alpha', matches)
    nt.assert_in('\\aleph', matches)

def test_abspath_file_completions():
    ip = get_ipython()
    with TemporaryDirectory() as tmpdir:
        prefix = os.path.join(tmpdir, 'foo')
        suffixes = ['1', '2']
        names = [prefix+s for s in suffixes]
        for n in names:
            open(n, 'w').close()

        # Check simple completion
        c = ip.complete(prefix)[1]
        nt.assert_equal(c, names)

        # Now check with a function call
        cmd = 'a = f("%s' % prefix
        c = ip.complete(prefix, cmd)[1]
        comp = [prefix+s for s in suffixes]
        nt.assert_equal(c, comp)

def test_local_file_completions():
    ip = get_ipython()
    with TemporaryWorkingDirectory():
        prefix = './foo'
        suffixes = ['1', '2']
        names = [prefix+s for s in suffixes]
        for n in names:
            open(n, 'w').close()

        # Check simple completion
        c = ip.complete(prefix)[1]
        nt.assert_equal(c, names)

        # Now check with a function call
        cmd = 'a = f("%s' % prefix
        c = ip.complete(prefix, cmd)[1]
        comp = set(prefix+s for s in suffixes)
        nt.assert_true(comp.issubset(set(c)))

def test_line_cell_magics():
    from IPython.core.magic import register_line_cell_magic

    @register_line_cell_magic
    def _bar_cellm(line, cell):
        pass

    ip = get_ipython()
    c = ip.Completer

    # The policy here is trickier, see comments in completion code.  The
    # returned values depend on whether the user passes %% or not explicitly,
    # and this will show a difference if the same name is both a line and cell
    # magic.
    s, matches = c.complete(None, '_bar_ce')
    nt.assert_in('%_bar_cellm', matches)
    nt.assert_in('%%_bar_cellm', matches)
    s, matches = c.complete(None, '%_bar_ce')
    nt.assert_in('%_bar_cellm', matches)
    nt.assert_in('%%_bar_cellm', matches)
    s, matches = c.complete(None, '%%_bar_ce')
    nt.assert_not_in('%_bar_cellm', matches)
    nt.assert_in('%%_bar_cellm', matches)

def test_magic_color():
    ip = get_ipython()
    c = ip.Completer

    s, matches = c.complete(None, 'colo')
    nt.assert_in('%colors', matches)
    s, matches = c.complete(None, 'colo')
    nt.assert_not_in('NoColor', matches)
    s, matches = c.complete(None, 'colors ')
    nt.assert_in('NoColor', matches)
    s, matches = c.complete(None, '%colors ')
    nt.assert_in('NoColor', matches)
    s, matches = c.complete(None, 'colors NoCo')
    nt.assert_list_equal(['NoColor'], matches)
    s, matches = c.complete(None, '%colors NoCo')
    nt.assert_list_equal(['NoColor'], matches)

def test_dict_key_completion_unicode_py3():
    """Test handling of unicode in dict key completion"""
    ip = get_ipython()
    complete = ip.Completer.complete

    ip.user_ns['d'] = {u'a\u05d0': None}

    # query using escape
    if sys.platform != 'win32':
        # Known failure on Windows
        _, matches = complete(line_buffer="d['a\\u05d0")
        nt.assert_in("u05d0", matches)  # tokenized after \\

    # query using character
    _, matches = complete(line_buffer="d['a\u05d0")
    nt.assert_in(u"a\u05d0", matches)

    with greedy_completion():
        # query using escape
        _, matches = complete(line_buffer="d['a\\u05d0")
        nt.assert_in("d['a\\u05d0']", matches)  # tokenized after \\

        # query using character
        _, matches = complete(line_buffer="d['a\u05d0")
        nt.assert_in(u"d['a\u05d0']", matches)

def test_dict_key_completion_invalids():
    """Smoke test cases dict key completion can't handle"""
    ip = get_ipython()
    complete = ip.Completer.complete

    ip.user_ns['no_getitem'] = None
    ip.user_ns['no_keys'] = []
    ip.user_ns['cant_call_keys'] = dict
    ip.user_ns['empty'] = {}
    ip.user_ns['d'] = {'abc': 5}

    _, matches = complete(line_buffer="no_getitem['")
    _, matches = complete(line_buffer="no_keys['")
    _, matches = complete(line_buffer="cant_call_keys['")
    _, matches = complete(line_buffer="empty['")
    _, matches = complete(line_buffer="name_error['")
    _, matches = complete(line_buffer="d['\\")  # incomplete escape

def test_tb_syntaxerror():
    """test %tb after a SyntaxError"""
    ip = get_ipython()
    ip.run_cell("for")

    # trap and validate stdout
    save_stdout = sys.stdout
    try:
        sys.stdout = StringIO()
        ip.run_cell("%tb")
        out = sys.stdout.getvalue()
    finally:
        sys.stdout = save_stdout
    # trim output, and only check the last line
    last_line = out.rstrip().splitlines()[-1].strip()
    nt.assert_equal(last_line, "SyntaxError: invalid syntax")

def doctest_precision():
    """doctest for %precision

    In [1]: f = get_ipython().display_formatter.formatters['text/plain']

    In [2]: %precision 5
    Out[2]: {u}'%.5f'

    In [3]: f.float_format
    Out[3]: {u}'%.5f'

    In [4]: %precision %e
    Out[4]: {u}'%e'

    In [5]: f(3.1415927)
    Out[5]: {u}'3.141593e+00'
    """

def test_file_amend():
    """%%file -a amends files"""
    ip = get_ipython()
    with TemporaryDirectory() as td:
        fname = os.path.join(td, 'file2')
        ip.run_cell_magic("file", fname, u'\n'.join([
            'line1',
            'line2',
        ]))
        ip.run_cell_magic("file", "-a %s" % fname, u'\n'.join([
            'line3',
            'line4',
        ]))
        with open(fname) as f:
            s = f.read()
        nt.assert_in('line1\n', s)
        nt.assert_in('line3\n', s)

def test_line_cell_info():
    """%%foo and %foo magics are distinguishable to inspect"""
    ip = get_ipython()
    ip.magics_manager.register(FooFoo)
    oinfo = ip.object_inspect('foo')
    nt.assert_true(oinfo['found'])
    nt.assert_true(oinfo['ismagic'])

    oinfo = ip.object_inspect('%%foo')
    nt.assert_true(oinfo['found'])
    nt.assert_true(oinfo['ismagic'])
    nt.assert_equal(oinfo['docstring'], FooFoo.cell_foo.__doc__)

    oinfo = ip.object_inspect('%foo')
    nt.assert_true(oinfo['found'])
    nt.assert_true(oinfo['ismagic'])
    nt.assert_equal(oinfo['docstring'], FooFoo.line_foo.__doc__)

def test_alias_magic():
    """Test %alias_magic."""
    ip = get_ipython()
    mm = ip.magics_manager

    # Basic operation: both cell and line magics are created, if possible.
    ip.run_line_magic('alias_magic', 'timeit_alias timeit')
    nt.assert_in('timeit_alias', mm.magics['line'])
    nt.assert_in('timeit_alias', mm.magics['cell'])

    # --cell is specified, line magic not created.
    ip.run_line_magic('alias_magic', '--cell timeit_cell_alias timeit')
    nt.assert_not_in('timeit_cell_alias', mm.magics['line'])
    nt.assert_in('timeit_cell_alias', mm.magics['cell'])

    # Test that line alias is created successfully.
    ip.run_line_magic('alias_magic', '--line env_alias env')
    nt.assert_equal(ip.run_line_magic('env', ''),
                    ip.run_line_magic('env_alias', ''))

    # Test that line alias with parameters passed in is created successfully.
    ip.run_line_magic('alias_magic', '--line history_alias history --params ' + shlex.quote('3'))
    nt.assert_in('history_alias', mm.magics['line'])

def test_save():
    """Test %save."""
    ip = get_ipython()
    ip.history_manager.reset()   # Clear any existing history.
    cmds = [u"a=1", u"def b():\n  return a**2", u"print(a, b())"]
    for i, cmd in enumerate(cmds, start=1):
        ip.history_manager.store_inputs(i, cmd)
    with TemporaryDirectory() as tmpdir:
        file = os.path.join(tmpdir, "testsave.py")
        ip.run_line_magic("save", "%s 1-10" % file)
        with open(file) as f:
            content = f.read()
            nt.assert_equal(content.count(cmds[0]), 1)
            nt.assert_in('coding: utf-8', content)
        ip.run_line_magic("save", "-a %s 1-10" % file)
        with open(file) as f:
            content = f.read()
            nt.assert_equal(content.count(cmds[0]), 2)
            nt.assert_in('coding: utf-8', content)

def test_store():
    """Test %store."""
    ip = get_ipython()
    ip.run_line_magic('load_ext', 'storemagic')

    # make sure the storage is empty
    ip.run_line_magic('store', '-z')
    ip.user_ns['var'] = 42
    ip.run_line_magic('store', 'var')
    ip.user_ns['var'] = 39
    ip.run_line_magic('store', '-r')
    nt.assert_equal(ip.user_ns['var'], 42)

    ip.run_line_magic('store', '-d var')
    ip.user_ns['var'] = 39
    ip.run_line_magic('store' , '-r')
    nt.assert_equal(ip.user_ns['var'], 39)

def _run_edit_test(arg_s, exp_filename=None,
                        exp_lineno=-1,
                        exp_contents=None,
                        exp_is_temp=None):
    ip = get_ipython()
    M = code.CodeMagics(ip)
    last_call = ['','']
    opts,args = M.parse_options(arg_s,'prxn:')
    filename, lineno, is_temp = M._find_edit_target(ip, args, opts, last_call)

    if exp_filename is not None:
        nt.assert_equal(exp_filename, filename)
    if exp_contents is not None:
        with io.open(filename, 'r', encoding='utf-8') as f:
            contents = f.read()
        nt.assert_equal(exp_contents, contents)
    if exp_lineno != -1:
        nt.assert_equal(exp_lineno, lineno)
    if exp_is_temp is not None:
        nt.assert_equal(exp_is_temp, is_temp)

def test_pass_correct_include_exclude():
    class Tester(object):

        def __init__(self, include=None, exclude=None):
            self.include = include
            self.exclude = exclude

        def _repr_mimebundle_(self, include, exclude, **kwargs):
            if include and (include != self.include):
                raise ValueError('include got modified: display() may be broken.')
            if exclude and (exclude != self.exclude):
                raise ValueError('exclude got modified: display() may be broken.')

            return None

    include = {'a', 'b', 'c'}
    exclude = {'c', 'e' , 'f'}

    f = get_ipython().display_formatter
    f.format(Tester(include=include, exclude=exclude), include=include, exclude=exclude)
    f.format(Tester(exclude=exclude), exclude=exclude)
    f.format(Tester(include=include), include=include)

def quick_completer(cmd, completions):
    """ Easily create a trivial completer for a command.

    Takes either a list of completions, or all completions in string (that will
    be split on whitespace).

    Example::

        [d:\ipython]|1> import ipy_completers
        [d:\ipython]|2> ipy_completers.quick_completer('foo', ['bar','baz'])
        [d:\ipython]|3> foo b<TAB>
        bar baz
        [d:\ipython]|3> foo ba
    """

    if isinstance(completions, str):
        completions = completions.split()

    def do_complete(self, event):
        return completions

    get_ipython().set_hook('complete_command',do_complete, str_key = cmd)

def can_use_widgets():
    """ Expanded from from http://stackoverflow.com/a/34092072/1958900
    """
    if 'IPython' not in sys.modules:
        # IPython hasn't been imported, definitely not
        return False
    from IPython import get_ipython

    # check for `kernel` attribute on the IPython instance
    if getattr(get_ipython(), 'kernel', None) is None:
        return False

    try:
        import ipywidgets as ipy
        import traitlets
    except ImportError:
        return False

    return True

def page(data, start=0, screen_lines=0, pager_cmd=None):
    """Display content in a pager, piping through a pager after a certain length.

    data can be a mime-bundle dict, supplying multiple representations,
    keyed by mime-type, or text.

    Pager is dispatched via the `show_in_pager` IPython hook.
    If no hook is registered, `pager_page` will be used.
    """
    # Some routines may auto-compute start offsets incorrectly and pass a
    # negative value.  Offset to 0 for robustness.
    start = max(0, start)

    # first, try the hook
    ip = get_ipython()
    if ip:
        try:
            ip.hooks.show_in_pager(data, start=start, screen_lines=screen_lines)
            return
        except TryNext:
            pass

    # fallback on default pager
    return pager_page(data, start, screen_lines, pager_cmd)

def test_latex_completions():
    from IPython.core.latex_symbols import latex_symbols
    import random
    ip = get_ipython()
    # Test some random unicode symbols
    keys = random.sample(latex_symbols.keys(), 10)
    for k in keys:
        text, matches = ip.complete(k)
        nt.assert_equal(len(matches),1)
        nt.assert_equal(text, k)
        nt.assert_equal(matches[0], latex_symbols[k])
    # Test a more complex line
    text, matches = ip.complete(u'print(\\alpha')
    nt.assert_equals(text, u'\\alpha')
    nt.assert_equals(matches[0], latex_symbols['\\alpha'])
    # Test multiple matching latex symbols
    text, matches = ip.complete(u'\\al')
    nt.assert_in('\\alpha', matches)
    nt.assert_in('\\aleph', matches)

def test_abspath_file_completions():
    ip = get_ipython()
    with TemporaryDirectory() as tmpdir:
        prefix = os.path.join(tmpdir, 'foo')
        suffixes = ['1', '2']
        names = [prefix+s for s in suffixes]
        for n in names:
            open(n, 'w').close()

        # Check simple completion
        c = ip.complete(prefix)[1]
        nt.assert_equal(c, names)

        # Now check with a function call
        cmd = 'a = f("%s' % prefix
        c = ip.complete(prefix, cmd)[1]
        comp = [prefix+s for s in suffixes]
        nt.assert_equal(c, comp)

def test_local_file_completions():
    ip = get_ipython()
    with TemporaryWorkingDirectory():
        prefix = './foo'
        suffixes = ['1', '2']
        names = [prefix+s for s in suffixes]
        for n in names:
            open(n, 'w').close()

        # Check simple completion
        c = ip.complete(prefix)[1]
        nt.assert_equal(c, names)

        # Now check with a function call
        cmd = 'a = f("%s' % prefix
        c = ip.complete(prefix, cmd)[1]
        comp = set(prefix+s for s in suffixes)
        nt.assert_true(comp.issubset(set(c)))

def test_line_cell_magics():
    from IPython.core.magic import register_line_cell_magic

    @register_line_cell_magic
    def _bar_cellm(line, cell):
        pass

    ip = get_ipython()
    c = ip.Completer

    # The policy here is trickier, see comments in completion code.  The
    # returned values depend on whether the user passes %% or not explicitly,
    # and this will show a difference if the same name is both a line and cell
    # magic.
    s, matches = c.complete(None, '_bar_ce')
    nt.assert_in('%_bar_cellm', matches)
    nt.assert_in('%%_bar_cellm', matches)
    s, matches = c.complete(None, '%_bar_ce')
    nt.assert_in('%_bar_cellm', matches)
    nt.assert_in('%%_bar_cellm', matches)
    s, matches = c.complete(None, '%%_bar_ce')
    nt.assert_not_in('%_bar_cellm', matches)
    nt.assert_in('%%_bar_cellm', matches)

def test_struct_array_key_completion():
    """Test dict key completion applies to numpy struct arrays"""
    import numpy
    ip = get_ipython()
    complete = ip.Completer.complete
    ip.user_ns['d'] = numpy.array([], dtype=[('hello', 'f'), ('world', 'f')])
    _, matches = complete(line_buffer="d['")
    nt.assert_in("hello", matches)
    nt.assert_in("world", matches)
    # complete on the numpy struct itself
    dt = numpy.dtype([('my_head', [('my_dt', '>u4'), ('my_df', '>u4')]),
                      ('my_data', '>f4', 5)])
    x = numpy.zeros(2, dtype=dt)
    ip.user_ns['d'] = x[1]
    _, matches = complete(line_buffer="d['")
    nt.assert_in("my_head", matches)
    nt.assert_in("my_data", matches)
    # complete on a nested level
    with greedy_completion():
        ip.user_ns['d'] = numpy.zeros(2, dtype=dt)
        _, matches = complete(line_buffer="d[1]['my_head']['")
        nt.assert_true(any(["my_dt" in m for m in matches]))
        nt.assert_true(any(["my_df" in m for m in matches]))

def test_dict_key_completion_invalids():
    """Smoke test cases dict key completion can't handle"""
    ip = get_ipython()
    complete = ip.Completer.complete

    ip.user_ns['no_getitem'] = None
    ip.user_ns['no_keys'] = []
    ip.user_ns['cant_call_keys'] = dict
    ip.user_ns['empty'] = {}
    ip.user_ns['d'] = {'abc': 5}

    _, matches = complete(line_buffer="no_getitem['")
    _, matches = complete(line_buffer="no_keys['")
    _, matches = complete(line_buffer="cant_call_keys['")
    _, matches = complete(line_buffer="empty['")
    _, matches = complete(line_buffer="name_error['")
    _, matches = complete(line_buffer="d['\\")  # incomplete escape

def test_tb_syntaxerror():
    """test %tb after a SyntaxError"""
    ip = get_ipython()
    ip.run_cell("for")

    # trap and validate stdout
    save_stdout = sys.stdout
    try:
        sys.stdout = StringIO()
        ip.run_cell("%tb")
        out = sys.stdout.getvalue()
    finally:
        sys.stdout = save_stdout
    # trim output, and only check the last line
    last_line = out.rstrip().splitlines()[-1].strip()
    nt.assert_equal(last_line, "SyntaxError: invalid syntax")

def doctest_precision():
    """doctest for %precision

    In [1]: f = get_ipython().display_formatter.formatters['text/plain']

    In [2]: %precision 5
    Out[2]: {u}'%.5f'

    In [3]: f.float_format
    Out[3]: {u}'%.5f'

    In [4]: %precision %e
    Out[4]: {u}'%e'

    In [5]: f(3.1415927)
    Out[5]: {u}'3.141593e+00'
    """

def test_file_amend():
    """%%file -a amends files"""
    ip = get_ipython()
    with TemporaryDirectory() as td:
        fname = os.path.join(td, 'file2')
        ip.run_cell_magic("file", fname, u'\n'.join([
            'line1',
            'line2',
        ]))
        ip.run_cell_magic("file", "-a %s" % fname, u'\n'.join([
            'line3',
            'line4',
        ]))
        with open(fname) as f:
            s = f.read()
        nt.assert_in('line1\n', s)
        nt.assert_in('line3\n', s)

def test_line_cell_info():
    """%%foo and %foo magics are distinguishable to inspect"""
    ip = get_ipython()
    ip.magics_manager.register(FooFoo)
    oinfo = ip.object_inspect('foo')
    nt.assert_true(oinfo['found'])
    nt.assert_true(oinfo['ismagic'])

    oinfo = ip.object_inspect('%%foo')
    nt.assert_true(oinfo['found'])
    nt.assert_true(oinfo['ismagic'])
    nt.assert_equal(oinfo['docstring'], FooFoo.cell_foo.__doc__)

    oinfo = ip.object_inspect('%foo')
    nt.assert_true(oinfo['found'])
    nt.assert_true(oinfo['ismagic'])
    nt.assert_equal(oinfo['docstring'], FooFoo.line_foo.__doc__)

def test_alias_magic():
    """Test %alias_magic."""
    ip = get_ipython()
    mm = ip.magics_manager

    # Basic operation: both cell and line magics are created, if possible.
    ip.run_line_magic('alias_magic', 'timeit_alias timeit')
    nt.assert_in('timeit_alias', mm.magics['line'])
    nt.assert_in('timeit_alias', mm.magics['cell'])

    # --cell is specified, line magic not created.
    ip.run_line_magic('alias_magic', '--cell timeit_cell_alias timeit')
    nt.assert_not_in('timeit_cell_alias', mm.magics['line'])
    nt.assert_in('timeit_cell_alias', mm.magics['cell'])

    # Test that line alias is created successfully.
    ip.run_line_magic('alias_magic', '--line env_alias env')
    nt.assert_equal(ip.run_line_magic('env', ''),
                    ip.run_line_magic('env_alias', ''))

def test_save():
    """Test %save."""
    ip = get_ipython()
    ip.history_manager.reset()   # Clear any existing history.
    cmds = [u"a=1", u"def b():\n  return a**2", u"print(a, b())"]
    for i, cmd in enumerate(cmds, start=1):
        ip.history_manager.store_inputs(i, cmd)
    with TemporaryDirectory() as tmpdir:
        file = os.path.join(tmpdir, "testsave.py")
        ip.run_line_magic("save", "%s 1-10" % file)
        with open(file) as f:
            content = f.read()
            nt.assert_equal(content.count(cmds[0]), 1)
            nt.assert_in('coding: utf-8', content)
        ip.run_line_magic("save", "-a %s 1-10" % file)
        with open(file) as f:
            content = f.read()
            nt.assert_equal(content.count(cmds[0]), 2)
            nt.assert_in('coding: utf-8', content)

def test_store():
    """Test %store."""
    ip = get_ipython()
    ip.run_line_magic('load_ext', 'storemagic')

    # make sure the storage is empty
    ip.run_line_magic('store', '-z')
    ip.user_ns['var'] = 42
    ip.run_line_magic('store', 'var')
    ip.user_ns['var'] = 39
    ip.run_line_magic('store', '-r')
    nt.assert_equal(ip.user_ns['var'], 42)

    ip.run_line_magic('store', '-d var')
    ip.user_ns['var'] = 39
    ip.run_line_magic('store' , '-r')
    nt.assert_equal(ip.user_ns['var'], 39)

def quick_completer(cmd, completions):
    """ Easily create a trivial completer for a command.

    Takes either a list of completions, or all completions in string (that will
    be split on whitespace).

    Example::

        [d:\ipython]|1> import ipy_completers
        [d:\ipython]|2> ipy_completers.quick_completer('foo', ['bar','baz'])
        [d:\ipython]|3> foo b<TAB>
        bar baz
        [d:\ipython]|3> foo ba
    """

    if isinstance(completions, string_types):
        completions = completions.split()

    def do_complete(self, event):
        return completions

    get_ipython().set_hook('complete_command',do_complete, str_key = cmd)

def _attached_to_ipy_notebook_with_widgets():
    try:
        # check for widgets
        import ipywidgets
        if ipywidgets.version_info[0] < 4:
            raise ImportError()
        # check for ipython kernel
        from IPython import get_ipython
        ip = get_ipython()
        if ip is None:
            return False
        if not getattr(ip, 'kernel', None):
            return False
        # No further checks are feasible
        return True
    except ImportError:
        return False

def get_config():
    ip = get_ipython()

    if ip is None:
        profile_dir = paths.locate_profile()
    else:
        profile_dir = ip.profile_dir.location

    json_path = path.join(profile_dir, "ipython_config.json")

    try:
        with open(json_path, 'r') as f:
            config = json.load(f)
    except (FileNotFoundError, json.decoder.JSONDecodeError):
        config = {}
    return config, json_path

def test_create_cell_debug(self, mock_default_context, mock_notebook_environment):
    env = {}
    mock_default_context.return_value = TestCases._create_context()
    mock_notebook_environment.return_value = env
    IPython.get_ipython().user_ns = env

    # cell output is empty when debug is True
    output = google.datalab.contrib.pipeline.commands._pipeline._create_cell(
        {'name': 'foo_pipeline', 'debug': True}, self.sample_cell_body)
    self.assertTrue(len(output) > 0)

    output = google.datalab.contrib.pipeline.commands._pipeline._create_cell(
        {'name': 'foo_pipeline', 'debug': False}, self.sample_cell_body)
    self.assertTrue(output is None)

    output = google.datalab.contrib.pipeline.commands._pipeline._create_cell(
        {'name': 'foo_pipeline'}, self.sample_cell_body)
    self.assertTrue(output is None)

def _view(args, cell):
  csv = datalab.data.Csv(args['input'])
  num_lines = int(args['count'] or 5)
  headers = None
  if cell:
    ipy = IPython.get_ipython()
    config = _utils.parse_config(cell, ipy.user_ns)
    if 'columns' in config:
      headers = [e.strip() for e in config['columns'].split(',')]
  df = pd.DataFrame(csv.browse(num_lines, headers))
  if args['profile']:
    # TODO(gram): We need to generate a schema and type-convert the columns before this
    # will be useful for CSV
    return _utils.profile_df(df)
  else:
    return IPython.core.display.HTML(df.to_html(index=False))

def _view(args, cell):
  csv = google.datalab.data.CsvFile(args['input'])
  num_lines = int(args['count'] or 5)
  headers = None
  if cell:
    ipy = IPython.get_ipython()
    config = _utils.parse_config(cell, ipy.user_ns)
    if 'columns' in config:
      headers = [e.strip() for e in config['columns'].split(',')]
  df = pd.DataFrame(csv.browse(num_lines, headers))
  if args['profile']:
    # TODO(gram): We need to generate a schema and type-convert the columns before this
    # will be useful for CSV
    return _utils.profile_df(df)
  else:
    return IPython.core.display.HTML(df.to_html(index=False))

def page(data, start=0, screen_lines=0, pager_cmd=None):
    """Display content in a pager, piping through a pager after a certain length.

    data can be a mime-bundle dict, supplying multiple representations,
    keyed by mime-type, or text.

    Pager is dispatched via the `show_in_pager` IPython hook.
    If no hook is registered, `pager_page` will be used.
    """
    # Some routines may auto-compute start offsets incorrectly and pass a
    # negative value.  Offset to 0 for robustness.
    start = max(0, start)

    # first, try the hook
    ip = get_ipython()
    if ip:
        try:
            ip.hooks.show_in_pager(data, start=start, screen_lines=screen_lines)
            return
        except TryNext:
            pass

    # fallback on default pager
    return pager_page(data, start, screen_lines, pager_cmd)

def test_latex_completions():
    from IPython.core.latex_symbols import latex_symbols
    import random
    ip = get_ipython()
    # Test some random unicode symbols
    keys = random.sample(latex_symbols.keys(), 10)
    for k in keys:
        text, matches = ip.complete(k)
        nt.assert_equal(len(matches),1)
        nt.assert_equal(text, k)
        nt.assert_equal(matches[0], latex_symbols[k])
    # Test a more complex line
    text, matches = ip.complete(u'print(\\alpha')
    nt.assert_equals(text, u'\\alpha')
    nt.assert_equals(matches[0], latex_symbols['\\alpha'])
    # Test multiple matching latex symbols
    text, matches = ip.complete(u'\\al')
    nt.assert_in('\\alpha', matches)
    nt.assert_in('\\aleph', matches)

def test_abspath_file_completions():
    ip = get_ipython()
    with TemporaryDirectory() as tmpdir:
        prefix = os.path.join(tmpdir, 'foo')
        suffixes = ['1', '2']
        names = [prefix+s for s in suffixes]
        for n in names:
            open(n, 'w').close()

        # Check simple completion
        c = ip.complete(prefix)[1]
        nt.assert_equal(c, names)

        # Now check with a function call
        cmd = 'a = f("%s' % prefix
        c = ip.complete(prefix, cmd)[1]
        comp = [prefix+s for s in suffixes]
        nt.assert_equal(c, comp)

def test_local_file_completions():
    ip = get_ipython()
    with TemporaryWorkingDirectory():
        prefix = './foo'
        suffixes = ['1', '2']
        names = [prefix+s for s in suffixes]
        for n in names:
            open(n, 'w').close()

        # Check simple completion
        c = ip.complete(prefix)[1]
        nt.assert_equal(c, names)

        # Now check with a function call
        cmd = 'a = f("%s' % prefix
        c = ip.complete(prefix, cmd)[1]
        comp = set(prefix+s for s in suffixes)
        nt.assert_true(comp.issubset(set(c)))

def find_module(self, fullname, path=None):
        if self._called:
            # already handled
            return

        if fullname not in ('pylab', 'matplotlib.pyplot'):
            # not matplotlib
            return

        # don't call me again
        self._called = True

        try:
            # remove myself from the import hooks
            sys.meta_path = [loader for loader in sys.meta_path if loader is not self]
        except ValueError:
            pass

        ip = get_ipython()
        if ip is None:
            # not in an interactive environment
            return

        if ip.pylab_gui_select:
            # backend already selected
            return

        if hasattr(ip, 'kernel'):
            # default to inline in kernel environments
            ip.enable_matplotlib('inline')
        else:
            print('enabling matplotlib')
            ip.enable_matplotlib()

# install the finder immediately

def __init__(self, nb_path, ns=None):
        self.nb_path = nb_path
        if ns is None:
            self.ns = dict()
        else:
            self.ns = ns
        if 'get_ipython' not in self.ns:
            # not sure if thats really needed
            self.ns['get_ipython'] = get_ipython

        self.shell = InteractiveShell.instance()        
        self.refresh()
        self.run_tag('__init__', strict=False)

def __init__(self, id=None, on_msg=None):
        """
        Initializes a Comms object
        """
        self.id = id if id else uuid.uuid4().hex
        self._on_msg = on_msg
        self._comm = None

        from IPython import get_ipython
        self.manager = get_ipython().kernel.comm_manager
        self.manager.register_target(self.id, self._handle_open)

def is_kernel():
    """Detects if running in an IPython session
    """
    if 'IPython' not in sys.modules:
        # IPython hasn't been imported, definitely not
        return False
    from IPython import get_ipython
    # check for `kernel` attribute on the IPython instance
    return getattr(get_ipython(), 'kernel', None) is not None

def time_dense_solvers():
    instructions = {
        solver: "u = solve_qp(P_array, q, G_array, h, solver='%s')" % solver
        for solver in dense_solvers}
    print "\nDense solvers",
    print "\n-------------"
    for solver, instr in instructions.iteritems():
        print "%s: " % solver,
        get_ipython().magic(u'timeit %s' % instr)

def time_sparse_solvers():
    instructions = {
        solver: "u = solve_qp(P, q, G, h, solver='%s')" % solver
        for solver in sparse_solvers}
    print "\nSparse solvers",
    print "\n--------------"
    for solver, instr in instructions.iteritems():
        print "%s: " % solver,
        get_ipython().magic(u'timeit %s' % instr)