Merge pull request #13385 from nicolaslazo/master

Expand ~ in filename arguments for %notebook, %save and %history magics

IPython/core/magics/basic.py

@@ -1,658 +1,660
 """Implementation of basic magic functions."""
 
 
 import argparse
 from logging import error
 import io
+import os
 from pprint import pformat
 import sys
 from warnings import warn
 
 from traitlets.utils.importstring import import_item
 from IPython.core import magic_arguments, page
 from IPython.core.error import UsageError
 from IPython.core.magic import Magics, magics_class, line_magic, magic_escapes
 from IPython.utils.text import format_screen, dedent, indent
 from IPython.testing.skipdoctest import skip_doctest
 from IPython.utils.ipstruct import Struct
 
 
 class MagicsDisplay(object):
     def __init__(self, magics_manager, ignore=None):
         self.ignore = ignore if ignore else []
         self.magics_manager = magics_manager
     
     def _lsmagic(self):
         """The main implementation of the %lsmagic"""
         mesc = magic_escapes['line']
         cesc = magic_escapes['cell']
         mman = self.magics_manager
         magics = mman.lsmagic()
         out = ['Available line magics:',
                mesc + ('  '+mesc).join(sorted([m for m,v in magics['line'].items() if (v not in self.ignore)])),
                '',
                'Available cell magics:',
                cesc + ('  '+cesc).join(sorted([m for m,v in magics['cell'].items() if (v not in self.ignore)])),
                '',
                mman.auto_status()]
         return '\n'.join(out)
 
     def _repr_pretty_(self, p, cycle):
         p.text(self._lsmagic())
     
     def __str__(self):
         return self._lsmagic()
     
     def _jsonable(self):
         """turn magics dict into jsonable dict of the same structure
         
         replaces object instances with their class names as strings
         """
         magic_dict = {}
         mman = self.magics_manager
         magics = mman.lsmagic()
         for key, subdict in magics.items():
             d = {}
             magic_dict[key] = d
             for name, obj in subdict.items():
                 try:
                     classname = obj.__self__.__class__.__name__
                 except AttributeError:
                     classname = 'Other'
                 
                 d[name] = classname
         return magic_dict
         
     def _repr_json_(self):
         return self._jsonable()
 
 
 @magics_class
 class BasicMagics(Magics):
     """Magics that provide central IPython functionality.
 
     These are various magics that don't fit into specific categories but that
     are all part of the base 'IPython experience'."""
 
     @skip_doctest
     @magic_arguments.magic_arguments()
     @magic_arguments.argument(
         '-l', '--line', action='store_true',
         help="""Create a line magic alias."""
     )
     @magic_arguments.argument(
         '-c', '--cell', action='store_true',
         help="""Create a cell magic alias."""
     )
     @magic_arguments.argument(
         'name',
         help="""Name of the magic to be created."""
     )
     @magic_arguments.argument(
         'target',
         help="""Name of the existing line or cell magic."""
     )
     @magic_arguments.argument(
         '-p', '--params', default=None,
         help="""Parameters passed to the magic function."""
     )
     @line_magic
     def alias_magic(self, line=''):
         """Create an alias for an existing line or cell magic.
 
         Examples
         --------
         ::
 
           In [1]: %alias_magic t timeit
           Created `%t` as an alias for `%timeit`.
           Created `%%t` as an alias for `%%timeit`.
 
           In [2]: %t -n1 pass
           1 loops, best of 3: 954 ns per loop
 
           In [3]: %%t -n1
              ...: pass
              ...:
           1 loops, best of 3: 954 ns per loop
 
           In [4]: %alias_magic --cell whereami pwd
           UsageError: Cell magic function `%%pwd` not found.
           In [5]: %alias_magic --line whereami pwd
           Created `%whereami` as an alias for `%pwd`.
 
           In [6]: %whereami
           Out[6]: u'/home/testuser'
           
           In [7]: %alias_magic h history "-p -l 30" --line
           Created `%h` as an alias for `%history -l 30`.
         """
 
         args = magic_arguments.parse_argstring(self.alias_magic, line)
         shell = self.shell
         mman = self.shell.magics_manager
         escs = ''.join(magic_escapes.values())
 
         target = args.target.lstrip(escs)
         name = args.name.lstrip(escs)
 
         params = args.params
         if (params and
                 ((params.startswith('"') and params.endswith('"'))
                 or (params.startswith("'") and params.endswith("'")))):
             params = params[1:-1]
 
         # Find the requested magics.
         m_line = shell.find_magic(target, 'line')
         m_cell = shell.find_magic(target, 'cell')
         if args.line and m_line is None:
             raise UsageError('Line magic function `%s%s` not found.' %
                              (magic_escapes['line'], target))
         if args.cell and m_cell is None:
             raise UsageError('Cell magic function `%s%s` not found.' %
                              (magic_escapes['cell'], target))
 
         # If --line and --cell are not specified, default to the ones
         # that are available.
         if not args.line and not args.cell:
             if not m_line and not m_cell:
                 raise UsageError(
                     'No line or cell magic with name `%s` found.' % target
                 )
             args.line = bool(m_line)
             args.cell = bool(m_cell)
 
         params_str = "" if params is None else " " + params
 
         if args.line:
             mman.register_alias(name, target, 'line', params)
             print('Created `%s%s` as an alias for `%s%s%s`.' % (
                 magic_escapes['line'], name,
                 magic_escapes['line'], target, params_str))
 
         if args.cell:
             mman.register_alias(name, target, 'cell', params)
             print('Created `%s%s` as an alias for `%s%s%s`.' % (
                 magic_escapes['cell'], name,
                 magic_escapes['cell'], target, params_str))
 
     @line_magic
     def lsmagic(self, parameter_s=''):
         """List currently available magic functions."""
         return MagicsDisplay(self.shell.magics_manager, ignore=[])
 
     def _magic_docs(self, brief=False, rest=False):
         """Return docstrings from magic functions."""
         mman = self.shell.magics_manager
         docs = mman.lsmagic_docs(brief, missing='No documentation')
 
         if rest:
             format_string = '**%s%s**::\n\n%s\n\n'
         else:
             format_string = '%s%s:\n%s\n'
 
         return ''.join(
             [format_string % (magic_escapes['line'], fname,
                               indent(dedent(fndoc)))
              for fname, fndoc in sorted(docs['line'].items())]
             +
             [format_string % (magic_escapes['cell'], fname,
                               indent(dedent(fndoc)))
              for fname, fndoc in sorted(docs['cell'].items())]
         )
 
     @line_magic
     def magic(self, parameter_s=''):
         """Print information about the magic function system.
 
         Supported formats: -latex, -brief, -rest
         """
 
         mode = ''
         try:
             mode = parameter_s.split()[0][1:]
         except IndexError:
             pass
 
         brief = (mode == 'brief')
         rest = (mode == 'rest')
         magic_docs = self._magic_docs(brief, rest)
 
         if mode == 'latex':
             print(self.format_latex(magic_docs))
             return
         else:
             magic_docs = format_screen(magic_docs)
 
         out = ["""
 IPython's 'magic' functions
 ===========================
 
 The magic function system provides a series of functions which allow you to
 control the behavior of IPython itself, plus a lot of system-type
 features. There are two kinds of magics, line-oriented and cell-oriented.
 
 Line magics are prefixed with the % character and work much like OS
 command-line calls: they get as an argument the rest of the line, where
 arguments are passed without parentheses or quotes.  For example, this will
 time the given statement::
 
         %timeit range(1000)
 
 Cell magics are prefixed with a double %%, and they are functions that get as
 an argument not only the rest of the line, but also the lines below it in a
 separate argument.  These magics are called with two arguments: the rest of the
 call line and the body of the cell, consisting of the lines below the first.
 For example::
 
         %%timeit x = numpy.random.randn((100, 100))
         numpy.linalg.svd(x)
 
 will time the execution of the numpy svd routine, running the assignment of x
 as part of the setup phase, which is not timed.
 
 In a line-oriented client (the terminal or Qt console IPython), starting a new
 input with %% will automatically enter cell mode, and IPython will continue
 reading input until a blank line is given.  In the notebook, simply type the
 whole cell as one entity, but keep in mind that the %% escape can only be at
 the very start of the cell.
 
 NOTE: If you have 'automagic' enabled (via the command line option or with the
 %automagic function), you don't need to type in the % explicitly for line
 magics; cell magics always require an explicit '%%' escape.  By default,
 IPython ships with automagic on, so you should only rarely need the % escape.
 
 Example: typing '%cd mydir' (without the quotes) changes your working directory
 to 'mydir', if it exists.
 
 For a list of the available magic functions, use %lsmagic. For a description
 of any of them, type %magic_name?, e.g. '%cd?'.
 
 Currently the magic system has the following functions:""",
        magic_docs,
        "Summary of magic functions (from %slsmagic):" % magic_escapes['line'],
        str(self.lsmagic()),
        ]
         page.page('\n'.join(out))
 
 
     @line_magic
     def page(self, parameter_s=''):
         """Pretty print the object and display it through a pager.
 
         %page [options] OBJECT
 
         If no object is given, use _ (last output).
 
         Options:
 
           -r: page str(object), don't pretty-print it."""
 
         # After a function contributed by Olivier Aubert, slightly modified.
 
         # Process options/args
         opts, args = self.parse_options(parameter_s, 'r')
         raw = 'r' in opts
 
         oname = args and args or '_'
         info = self.shell._ofind(oname)
         if info['found']:
             txt = (raw and str or pformat)( info['obj'] )
             page.page(txt)
         else:
             print('Object `%s` not found' % oname)
 
     @line_magic
     def pprint(self, parameter_s=''):
         """Toggle pretty printing on/off."""
         ptformatter = self.shell.display_formatter.formatters['text/plain']
         ptformatter.pprint = bool(1 - ptformatter.pprint)
         print('Pretty printing has been turned',
               ['OFF','ON'][ptformatter.pprint])
 
     @line_magic
     def colors(self, parameter_s=''):
         """Switch color scheme for prompts, info system and exception handlers.
 
         Currently implemented schemes: NoColor, Linux, LightBG.
 
         Color scheme names are not case-sensitive.
 
         Examples
         --------
         To get a plain black and white terminal::
 
           %colors nocolor
         """
         def color_switch_err(name):
             warn('Error changing %s color schemes.\n%s' %
                  (name, sys.exc_info()[1]), stacklevel=2)
 
 
         new_scheme = parameter_s.strip()
         if not new_scheme:
             raise UsageError(
                 "%colors: you must specify a color scheme. See '%colors?'")
         # local shortcut
         shell = self.shell
 
         # Set shell colour scheme
         try:
             shell.colors = new_scheme
             shell.refresh_style()
         except:
             color_switch_err('shell')
 
         # Set exception colors
         try:
             shell.InteractiveTB.set_colors(scheme = new_scheme)
             shell.SyntaxTB.set_colors(scheme = new_scheme)
         except:
             color_switch_err('exception')
 
         # Set info (for 'object?') colors
         if shell.color_info:
             try:
                 shell.inspector.set_active_scheme(new_scheme)
             except:
                 color_switch_err('object inspector')
         else:
             shell.inspector.set_active_scheme('NoColor')
 
     @line_magic
     def xmode(self, parameter_s=''):
         """Switch modes for the exception handlers.
 
         Valid modes: Plain, Context, Verbose, and Minimal.
 
         If called without arguments, acts as a toggle.
 
         When in verbose mode the value --show (and --hide) 
         will respectively show (or hide) frames with ``__tracebackhide__ =
         True`` value set.
         """
 
         def xmode_switch_err(name):
             warn('Error changing %s exception modes.\n%s' %
                  (name,sys.exc_info()[1]))
 
         shell = self.shell
         if parameter_s.strip() == "--show":
             shell.InteractiveTB.skip_hidden = False
             return
         if parameter_s.strip() == "--hide":
             shell.InteractiveTB.skip_hidden = True
             return
 
         new_mode = parameter_s.strip().capitalize()
         try:
             shell.InteractiveTB.set_mode(mode=new_mode)
             print('Exception reporting mode:',shell.InteractiveTB.mode)
         except:
             xmode_switch_err('user')
 
     @line_magic
     def quickref(self, arg):
         """ Show a quick reference sheet """
         from IPython.core.usage import quick_reference
         qr = quick_reference + self._magic_docs(brief=True)
         page.page(qr)
 
     @line_magic
     def doctest_mode(self, parameter_s=''):
         """Toggle doctest mode on and off.
 
         This mode is intended to make IPython behave as much as possible like a
         plain Python shell, from the perspective of how its prompts, exceptions
         and output look.  This makes it easy to copy and paste parts of a
         session into doctests.  It does so by:
 
         - Changing the prompts to the classic ``>>>`` ones.
         - Changing the exception reporting mode to 'Plain'.
         - Disabling pretty-printing of output.
 
         Note that IPython also supports the pasting of code snippets that have
         leading '>>>' and '...' prompts in them.  This means that you can paste
         doctests from files or docstrings (even if they have leading
         whitespace), and the code will execute correctly.  You can then use
         '%history -t' to see the translated history; this will give you the
         input after removal of all the leading prompts and whitespace, which
         can be pasted back into an editor.
 
         With these features, you can switch into this mode easily whenever you
         need to do testing and changes to doctests, without having to leave
         your existing IPython session.
         """
 
         # Shorthands
         shell = self.shell
         meta = shell.meta
         disp_formatter = self.shell.display_formatter
         ptformatter = disp_formatter.formatters['text/plain']
         # dstore is a data store kept in the instance metadata bag to track any
         # changes we make, so we can undo them later.
         dstore = meta.setdefault('doctest_mode',Struct())
         save_dstore = dstore.setdefault
 
         # save a few values we'll need to recover later
         mode = save_dstore('mode',False)
         save_dstore('rc_pprint',ptformatter.pprint)
         save_dstore('xmode',shell.InteractiveTB.mode)
         save_dstore('rc_separate_out',shell.separate_out)
         save_dstore('rc_separate_out2',shell.separate_out2)
         save_dstore('rc_separate_in',shell.separate_in)
         save_dstore('rc_active_types',disp_formatter.active_types)
 
         if not mode:
             # turn on
 
             # Prompt separators like plain python
             shell.separate_in = ''
             shell.separate_out = ''
             shell.separate_out2 = ''
 
 
             ptformatter.pprint = False
             disp_formatter.active_types = ['text/plain']
 
             shell.magic('xmode Plain')
         else:
             # turn off
             shell.separate_in = dstore.rc_separate_in
 
             shell.separate_out = dstore.rc_separate_out
             shell.separate_out2 = dstore.rc_separate_out2
 
             ptformatter.pprint = dstore.rc_pprint
             disp_formatter.active_types = dstore.rc_active_types
 
             shell.magic('xmode ' + dstore.xmode)
 
         # mode here is the state before we switch; switch_doctest_mode takes
         # the mode we're switching to.
         shell.switch_doctest_mode(not mode)
 
         # Store new mode and inform
         dstore.mode = bool(not mode)
         mode_label = ['OFF','ON'][dstore.mode]
         print('Doctest mode is:', mode_label)
 
     @line_magic
     def gui(self, parameter_s=''):
         """Enable or disable IPython GUI event loop integration.
 
         %gui [GUINAME]
 
         This magic replaces IPython's threaded shells that were activated
         using the (pylab/wthread/etc.) command line flags.  GUI toolkits
         can now be enabled at runtime and keyboard
         interrupts should work without any problems.  The following toolkits
         are supported:  wxPython, PyQt4, PyGTK, Tk and Cocoa (OSX)::
 
             %gui wx      # enable wxPython event loop integration
             %gui qt4|qt  # enable PyQt4 event loop integration
             %gui qt5     # enable PyQt5 event loop integration
             %gui gtk     # enable PyGTK event loop integration
             %gui gtk3    # enable Gtk3 event loop integration
             %gui gtk4    # enable Gtk4 event loop integration
             %gui tk      # enable Tk event loop integration
             %gui osx     # enable Cocoa event loop integration
                          # (requires %matplotlib 1.1)
             %gui         # disable all event loop integration
 
         WARNING:  after any of these has been called you can simply create
         an application object, but DO NOT start the event loop yourself, as
         we have already handled that.
         """
         opts, arg = self.parse_options(parameter_s, '')
         if arg=='': arg = None
         try:
             return self.shell.enable_gui(arg)
         except Exception as e:
             # print simple error message, rather than traceback if we can't
             # hook up the GUI
             error(str(e))
 
     @skip_doctest
     @line_magic
     def precision(self, s=''):
         """Set floating point precision for pretty printing.
 
         Can set either integer precision or a format string.
 
         If numpy has been imported and precision is an int,
         numpy display precision will also be set, via ``numpy.set_printoptions``.
 
         If no argument is given, defaults will be restored.
 
         Examples
         --------
         ::
 
             In [1]: from math import pi
 
             In [2]: %precision 3
             Out[2]: u'%.3f'
 
             In [3]: pi
             Out[3]: 3.142
 
             In [4]: %precision %i
             Out[4]: u'%i'
 
             In [5]: pi
             Out[5]: 3
 
             In [6]: %precision %e
             Out[6]: u'%e'
 
             In [7]: pi**10
             Out[7]: 9.364805e+04
 
             In [8]: %precision
             Out[8]: u'%r'
 
             In [9]: pi**10
             Out[9]: 93648.047476082982
         """
         ptformatter = self.shell.display_formatter.formatters['text/plain']
         ptformatter.float_precision = s
         return ptformatter.float_format
 
     @magic_arguments.magic_arguments()
     @magic_arguments.argument(
         'filename', type=str,
         help='Notebook name or filename'
     )
     @line_magic
     def notebook(self, s):
         """Export and convert IPython notebooks.
 
         This function can export the current IPython history to a notebook file.
         For example, to export the history to "foo.ipynb" do "%notebook foo.ipynb".
         """
         args = magic_arguments.parse_argstring(self.notebook, s)
+        outfname = os.path.expanduser(args.filename)
 
         from nbformat import write, v4
 
         cells = []
         hist = list(self.shell.history_manager.get_range())
         if(len(hist)<=1):
             raise ValueError('History is empty, cannot export')
         for session, execution_count, source in hist[:-1]:
             cells.append(v4.new_code_cell(
                 execution_count=execution_count,
                 source=source
             ))
         nb = v4.new_notebook(cells=cells)
-        with io.open(args.filename, 'w', encoding='utf-8') as f:
+        with io.open(outfname, "w", encoding="utf-8") as f:
             write(nb, f, version=4)
 
 @magics_class
 class AsyncMagics(BasicMagics):
 
     @line_magic
     def autoawait(self, parameter_s):
         """
         Allow to change the status of the autoawait option.
 
         This allow you to set a specific asynchronous code runner.
 
         If no value is passed, print the currently used asynchronous integration
         and whether it is activated.
 
         It can take a number of value evaluated in the following order:
 
         - False/false/off deactivate autoawait integration
         - True/true/on activate autoawait integration using configured default
           loop
         - asyncio/curio/trio activate autoawait integration and use integration
           with said library.
 
         - `sync` turn on the pseudo-sync integration (mostly used for
           `IPython.embed()` which does not run IPython with a real eventloop and
           deactivate running asynchronous code. Turning on Asynchronous code with
           the pseudo sync loop is undefined behavior and may lead IPython to crash.
 
         If the passed parameter does not match any of the above and is a python
         identifier, get said object from user namespace and set it as the
         runner, and activate autoawait. 
 
         If the object is a fully qualified object name, attempt to import it and
         set it as the runner, and activate autoawait.
         
         
         The exact behavior of autoawait is experimental and subject to change
         across version of IPython and Python.
         """
 
         param = parameter_s.strip()
         d = {True: "on", False: "off"}
 
         if not param:
             print("IPython autoawait is `{}`, and set to use `{}`".format(
                 d[self.shell.autoawait],
                 self.shell.loop_runner
             ))
             return None
 
         if param.lower() in ('false', 'off'):
             self.shell.autoawait = False
             return None
         if param.lower() in ('true', 'on'):
             self.shell.autoawait = True
             return None
 
         if param in self.shell.loop_runner_map:
             self.shell.loop_runner, self.shell.autoawait = self.shell.loop_runner_map[param]
             return None
 
         if param in self.shell.user_ns :
             self.shell.loop_runner = self.shell.user_ns[param]
             self.shell.autoawait = True
             return None
 
         runner = import_item(param)
 
         self.shell.loop_runner = runner
         self.shell.autoawait = True

IPython/core/magics/code.py

@@ -1,754 +1,755
 """Implementation of code management magic functions.
 """
 #-----------------------------------------------------------------------------
 #  Copyright (c) 2012 The IPython Development Team.
 #
 #  Distributed under the terms of the Modified BSD License.
 #
 #  The full license is in the file COPYING.txt, distributed with this software.
 #-----------------------------------------------------------------------------
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 
 # Stdlib
 import inspect
 import io
 import os
 import re
 import sys
 import ast
 from itertools import chain
 from urllib.request import Request, urlopen
 from urllib.parse import urlencode
 from pathlib import Path
 
 # Our own packages
 from IPython.core.error import TryNext, StdinNotImplementedError, UsageError
 from IPython.core.macro import Macro
 from IPython.core.magic import Magics, magics_class, line_magic
 from IPython.core.oinspect import find_file, find_source_lines
 from IPython.core.release import version
 from IPython.testing.skipdoctest import skip_doctest
 from IPython.utils.contexts import preserve_keys
 from IPython.utils.path import get_py_filename
 from warnings import warn
 from logging import error
 from IPython.utils.text import get_text_list
 
 #-----------------------------------------------------------------------------
 # Magic implementation classes
 #-----------------------------------------------------------------------------
 
 # Used for exception handling in magic_edit
 class MacroToEdit(ValueError): pass
 
 ipython_input_pat = re.compile(r"<ipython\-input\-(\d+)-[a-z\d]+>$")
 
 # To match, e.g. 8-10 1:5 :10 3-
 range_re = re.compile(r"""
 (?P<start>\d+)?
 ((?P<sep>[\-:])
  (?P<end>\d+)?)?
 $""", re.VERBOSE)
 
 
 def extract_code_ranges(ranges_str):
     """Turn a string of range for %%load into 2-tuples of (start, stop)
     ready to use as a slice of the content split by lines.
 
     Examples
     --------
     list(extract_input_ranges("5-10 2"))
     [(4, 10), (1, 2)]
     """
     for range_str in ranges_str.split():
         rmatch = range_re.match(range_str)
         if not rmatch:
             continue
         sep = rmatch.group("sep")
         start = rmatch.group("start")
         end = rmatch.group("end")
 
         if sep == '-':
             start = int(start) - 1 if start else None
             end = int(end) if end else None
         elif sep == ':':
             start = int(start) - 1 if start else None
             end = int(end) - 1 if end else None
         else:
             end = int(start)
             start = int(start) - 1
         yield (start, end)
 
 
 def extract_symbols(code, symbols):
     """
     Return a tuple  (blocks, not_found)
     where ``blocks`` is a list of code fragments
     for each symbol parsed from code, and ``not_found`` are
     symbols not found in the code.
 
     For example::
 
         In [1]: code = '''a = 10
            ...: def b(): return 42
            ...: class A: pass'''
 
         In [2]: extract_symbols(code, 'A,b,z')
         Out[2]: (['class A: pass\\n', 'def b(): return 42\\n'], ['z'])
     """
     symbols = symbols.split(',')
 
     # this will raise SyntaxError if code isn't valid Python
     py_code = ast.parse(code)
 
     marks = [(getattr(s, 'name', None), s.lineno) for s in py_code.body]
     code = code.split('\n')
 
     symbols_lines = {}
     
     # we already know the start_lineno of each symbol (marks). 
     # To find each end_lineno, we traverse in reverse order until each 
     # non-blank line
     end = len(code)  
     for name, start in reversed(marks):
         while not code[end - 1].strip():
             end -= 1
         if name:
             symbols_lines[name] = (start - 1, end)
         end = start - 1
 
     # Now symbols_lines is a map
     # {'symbol_name': (start_lineno, end_lineno), ...}
     
     # fill a list with chunks of codes for each requested symbol
     blocks = []
     not_found = []
     for symbol in symbols:
         if symbol in symbols_lines:
             start, end = symbols_lines[symbol]
             blocks.append('\n'.join(code[start:end]) + '\n')
         else:
             not_found.append(symbol)
 
     return blocks, not_found
 
 def strip_initial_indent(lines):
     """For %load, strip indent from lines until finding an unindented line.
 
     https://github.com/ipython/ipython/issues/9775
     """
     indent_re = re.compile(r'\s+')
 
     it = iter(lines)
     first_line = next(it)
     indent_match = indent_re.match(first_line)
 
     if indent_match:
         # First line was indented
         indent = indent_match.group()
         yield first_line[len(indent):]
 
         for line in it:
             if line.startswith(indent):
                 yield line[len(indent):]
             else:
                 # Less indented than the first line - stop dedenting
                 yield line
                 break
     else:
         yield first_line
 
     # Pass the remaining lines through without dedenting
     for line in it:
         yield line
 
 
 class InteractivelyDefined(Exception):
     """Exception for interactively defined variable in magic_edit"""
     def __init__(self, index):
         self.index = index
 
 
 @magics_class
 class CodeMagics(Magics):
     """Magics related to code management (loading, saving, editing, ...)."""
 
     def __init__(self, *args, **kwargs):
         self._knowntemps = set()
         super(CodeMagics, self).__init__(*args, **kwargs)
 
     @line_magic
     def save(self, parameter_s=''):
         """Save a set of lines or a macro to a given filename.
 
         Usage:\\
           %save [options] filename [history]
 
         Options:
 
           -r: use 'raw' input.  By default, the 'processed' history is used,
           so that magics are loaded in their transformed version to valid
           Python.  If this option is given, the raw input as typed as the
           command line is used instead.
           
           -f: force overwrite.  If file exists, %save will prompt for overwrite
           unless -f is given.
 
           -a: append to the file instead of overwriting it.
 
         The history argument uses the same syntax as %history for input ranges,
         then saves the lines to the filename you specify.
 
         If no ranges are specified, saves history of the current session up to
         this point.
 
         It adds a '.py' extension to the file if you don't do so yourself, and
         it asks for confirmation before overwriting existing files.
 
         If `-r` option is used, the default extension is `.ipy`.
         """
 
         opts,args = self.parse_options(parameter_s,'fra',mode='list')
         if not args:
             raise UsageError('Missing filename.')
         raw = 'r' in opts
         force = 'f' in opts
         append = 'a' in opts
         mode = 'a' if append else 'w'
         ext = '.ipy' if raw else '.py'
         fname, codefrom = args[0], " ".join(args[1:])
         if not fname.endswith(('.py','.ipy')):
             fname += ext
+        fname = os.path.expanduser(fname)
         file_exists = os.path.isfile(fname)
         if file_exists and not force and not append:
             try:
                 overwrite = self.shell.ask_yes_no('File `%s` exists. Overwrite (y/[N])? ' % fname, default='n')
             except StdinNotImplementedError:
                 print("File `%s` exists. Use `%%save -f %s` to force overwrite" % (fname, parameter_s))
                 return
             if not overwrite :
                 print('Operation cancelled.')
                 return
         try:
             cmds = self.shell.find_user_code(codefrom,raw)
         except (TypeError, ValueError) as e:
             print(e.args[0])
             return
         with io.open(fname, mode, encoding="utf-8") as f:
             if not file_exists or not append:
                 f.write("# coding: utf-8\n")
             f.write(cmds)
             # make sure we end on a newline
             if not cmds.endswith('\n'):
                 f.write('\n')
         print('The following commands were written to file `%s`:' % fname)
         print(cmds)
 
     @line_magic
     def pastebin(self, parameter_s=''):
         """Upload code to dpaste.com, returning the URL.
 
         Usage:\\
           %pastebin [-d "Custom description"][-e 24] 1-7
 
         The argument can be an input history range, a filename, or the name of a
         string or macro.
 
         If no arguments are given, uploads the history of this session up to
         this point.
 
         Options:
 
           -d: Pass a custom description. The default will say
               "Pasted from IPython".
           -e: Pass number of days for the link to be expired.
               The default will be 7 days.
         """
         opts, args = self.parse_options(parameter_s, "d:e:")
 
         try:
             code = self.shell.find_user_code(args)
         except (ValueError, TypeError) as e:
             print(e.args[0])
             return
 
         expiry_days = 7
         try:
             expiry_days = int(opts.get("e", 7))
         except ValueError as e:
             print(e.args[0].capitalize())
             return
         if expiry_days < 1 or expiry_days > 365:
             print("Expiry days should be in range of 1 to 365")
             return
 
         post_data = urlencode(
             {
                 "title": opts.get("d", "Pasted from IPython"),
                 "syntax": "python",
                 "content": code,
                 "expiry_days": expiry_days,
             }
         ).encode("utf-8")
 
         request = Request(
             "https://dpaste.com/api/v2/",
             headers={"User-Agent": "IPython v{}".format(version)},
         )
         response = urlopen(request, post_data)
         return response.headers.get('Location')
 
     @line_magic
     def loadpy(self, arg_s):
         """Alias of `%load`
 
         `%loadpy` has gained some flexibility and dropped the requirement of a `.py`
         extension. So it has been renamed simply into %load. You can look at
         `%load`'s docstring for more info.
         """
         self.load(arg_s)
 
     @line_magic
     def load(self, arg_s):
         """Load code into the current frontend.
 
         Usage:\\
           %load [options] source
 
           where source can be a filename, URL, input history range, macro, or
           element in the user namespace
 
         If no arguments are given, loads the history of this session up to this
         point.
 
         Options:
 
           -r <lines>: Specify lines or ranges of lines to load from the source.
           Ranges could be specified as x-y (x..y) or in python-style x:y 
           (x..(y-1)). Both limits x and y can be left blank (meaning the 
           beginning and end of the file, respectively).
 
           -s <symbols>: Specify function or classes to load from python source. 
 
           -y : Don't ask confirmation for loading source above 200 000 characters.
 
           -n : Include the user's namespace when searching for source code.
 
         This magic command can either take a local filename, a URL, an history
         range (see %history) or a macro as argument, it will prompt for
         confirmation before loading source with more than 200 000 characters, unless
         -y flag is passed or if the frontend does not support raw_input::
 
         %load
         %load myscript.py
         %load 7-27
         %load myMacro
         %load http://www.example.com/myscript.py
         %load -r 5-10 myscript.py
         %load -r 10-20,30,40: foo.py
         %load -s MyClass,wonder_function myscript.py
         %load -n MyClass
         %load -n my_module.wonder_function
         """
         opts,args = self.parse_options(arg_s,'yns:r:')
         search_ns = 'n' in opts
         contents = self.shell.find_user_code(args, search_ns=search_ns)
 
         if 's' in opts:
             try:
                 blocks, not_found = extract_symbols(contents, opts['s'])
             except SyntaxError:
                 # non python code
                 error("Unable to parse the input as valid Python code")
                 return
 
             if len(not_found) == 1:
                 warn('The symbol `%s` was not found' % not_found[0])
             elif len(not_found) > 1:
                 warn('The symbols %s were not found' % get_text_list(not_found,
                                                                      wrap_item_with='`')
                 )
 
             contents = '\n'.join(blocks)
 
         if 'r' in opts:
             ranges = opts['r'].replace(',', ' ')
             lines = contents.split('\n')
             slices = extract_code_ranges(ranges)
             contents = [lines[slice(*slc)] for slc in slices]
             contents = '\n'.join(strip_initial_indent(chain.from_iterable(contents)))
 
         l = len(contents)
 
         # 200 000 is ~ 2500 full 80 character lines
         # so in average, more than 5000 lines
         if l > 200000 and 'y' not in opts:
             try:
                 ans = self.shell.ask_yes_no(("The text you're trying to load seems pretty big"\
                 " (%d characters). Continue (y/[N]) ?" % l), default='n' )
             except StdinNotImplementedError:
                 #assume yes if raw input not implemented
                 ans = True
 
             if ans is False :
                 print('Operation cancelled.')
                 return
 
         contents = "# %load {}\n".format(arg_s) + contents
 
         self.shell.set_next_input(contents, replace=True)
 
     @staticmethod
     def _find_edit_target(shell, args, opts, last_call):
         """Utility method used by magic_edit to find what to edit."""
 
         def make_filename(arg):
             "Make a filename from the given args"
             try:
                 filename = get_py_filename(arg)
             except IOError:
                 # If it ends with .py but doesn't already exist, assume we want
                 # a new file.
                 if arg.endswith('.py'):
                     filename = arg
                 else:
                     filename = None
             return filename
 
         # Set a few locals from the options for convenience:
         opts_prev = 'p' in opts
         opts_raw = 'r' in opts
 
         # custom exceptions
         class DataIsObject(Exception): pass
 
         # Default line number value
         lineno = opts.get('n',None)
 
         if opts_prev:
             args = '_%s' % last_call[0]
             if args not in shell.user_ns:
                 args = last_call[1]
 
         # by default this is done with temp files, except when the given
         # arg is a filename
         use_temp = True
 
         data = ''
 
         # First, see if the arguments should be a filename.
         filename = make_filename(args)
         if filename:
             use_temp = False
         elif args:
             # Mode where user specifies ranges of lines, like in %macro.
             data = shell.extract_input_lines(args, opts_raw)
             if not data:
                 try:
                     # Load the parameter given as a variable. If not a string,
                     # process it as an object instead (below)
 
                     #print '*** args',args,'type',type(args)  # dbg
                     data = eval(args, shell.user_ns)
                     if not isinstance(data, str):
                         raise DataIsObject
 
                 except (NameError,SyntaxError):
                     # given argument is not a variable, try as a filename
                     filename = make_filename(args)
                     if filename is None:
                         warn("Argument given (%s) can't be found as a variable "
                              "or as a filename." % args)
                         return (None, None, None)
                     use_temp = False
 
                 except DataIsObject as e:
                     # macros have a special edit function
                     if isinstance(data, Macro):
                         raise MacroToEdit(data) from e
 
                     # For objects, try to edit the file where they are defined
                     filename = find_file(data)
                     if filename:
                         if 'fakemodule' in filename.lower() and \
                             inspect.isclass(data):
                             # class created by %edit? Try to find source
                             # by looking for method definitions instead, the
                             # __module__ in those classes is FakeModule.
                             attrs = [getattr(data, aname) for aname in dir(data)]
                             for attr in attrs:
                                 if not inspect.ismethod(attr):
                                     continue
                                 filename = find_file(attr)
                                 if filename and \
                                   'fakemodule' not in filename.lower():
                                     # change the attribute to be the edit
                                     # target instead
                                     data = attr
                                     break
                         
                         m = ipython_input_pat.match(os.path.basename(filename))
                         if m:
                             raise InteractivelyDefined(int(m.groups()[0])) from e
 
                         datafile = 1
                     if filename is None:
                         filename = make_filename(args)
                         datafile = 1
                         if filename is not None:
                             # only warn about this if we get a real name
                             warn('Could not find file where `%s` is defined.\n'
                              'Opening a file named `%s`' % (args, filename))
                     # Now, make sure we can actually read the source (if it was
                     # in a temp file it's gone by now).
                     if datafile:
                         if lineno is None:
                             lineno = find_source_lines(data)
                         if lineno is None:
                             filename = make_filename(args)
                             if filename is None:
                                 warn('The file where `%s` was defined '
                                      'cannot be read or found.' % data)
                                 return (None, None, None)
                     use_temp = False
 
         if use_temp:
             filename = shell.mktempfile(data)
             print('IPython will make a temporary file named:',filename)
 
         # use last_call to remember the state of the previous call, but don't
         # let it be clobbered by successive '-p' calls.
         try:
             last_call[0] = shell.displayhook.prompt_count
             if not opts_prev:
                 last_call[1] = args
         except:
             pass
 
 
         return filename, lineno, use_temp
 
     def _edit_macro(self,mname,macro):
         """open an editor with the macro data in a file"""
         filename = self.shell.mktempfile(macro.value)
         self.shell.hooks.editor(filename)
 
         # and make a new macro object, to replace the old one
         mvalue = Path(filename).read_text()
         self.shell.user_ns[mname] = Macro(mvalue)
 
     @skip_doctest
     @line_magic
     def edit(self, parameter_s='',last_call=['','']):
         """Bring up an editor and execute the resulting code.
 
         Usage:
           %edit [options] [args]
 
         %edit runs IPython's editor hook. The default version of this hook is
         set to call the editor specified by your $EDITOR environment variable.
         If this isn't found, it will default to vi under Linux/Unix and to
         notepad under Windows. See the end of this docstring for how to change
         the editor hook.
 
         You can also set the value of this editor via the
         ``TerminalInteractiveShell.editor`` option in your configuration file.
         This is useful if you wish to use a different editor from your typical
         default with IPython (and for Windows users who typically don't set
         environment variables).
 
         This command allows you to conveniently edit multi-line code right in
         your IPython session.
 
         If called without arguments, %edit opens up an empty editor with a
         temporary file and will execute the contents of this file when you
         close it (don't forget to save it!).
 
 
         Options:
 
         -n <number>: open the editor at a specified line number.  By default,
         the IPython editor hook uses the unix syntax 'editor +N filename', but
         you can configure this by providing your own modified hook if your
         favorite editor supports line-number specifications with a different
         syntax.
 
         -p: this will call the editor with the same data as the previous time
         it was used, regardless of how long ago (in your current session) it
         was.
 
         -r: use 'raw' input.  This option only applies to input taken from the
         user's history.  By default, the 'processed' history is used, so that
         magics are loaded in their transformed version to valid Python.  If
         this option is given, the raw input as typed as the command line is
         used instead.  When you exit the editor, it will be executed by
         IPython's own processor.
 
         -x: do not execute the edited code immediately upon exit. This is
         mainly useful if you are editing programs which need to be called with
         command line arguments, which you can then do using %run.
 
 
         Arguments:
 
         If arguments are given, the following possibilities exist:
 
         - If the argument is a filename, IPython will load that into the
           editor. It will execute its contents with execfile() when you exit,
           loading any code in the file into your interactive namespace.
 
         - The arguments are ranges of input history,  e.g. "7 ~1/4-6".
           The syntax is the same as in the %history magic.
 
         - If the argument is a string variable, its contents are loaded
           into the editor. You can thus edit any string which contains
           python code (including the result of previous edits).
 
         - If the argument is the name of an object (other than a string),
           IPython will try to locate the file where it was defined and open the
           editor at the point where it is defined. You can use `%edit function`
           to load an editor exactly at the point where 'function' is defined,
           edit it and have the file be executed automatically.
 
         - If the object is a macro (see %macro for details), this opens up your
           specified editor with a temporary file containing the macro's data.
           Upon exit, the macro is reloaded with the contents of the file.
 
         Note: opening at an exact line is only supported under Unix, and some
         editors (like kedit and gedit up to Gnome 2.8) do not understand the
         '+NUMBER' parameter necessary for this feature. Good editors like
         (X)Emacs, vi, jed, pico and joe all do.
 
         After executing your code, %edit will return as output the code you
         typed in the editor (except when it was an existing file). This way
         you can reload the code in further invocations of %edit as a variable,
         via _<NUMBER> or Out[<NUMBER>], where <NUMBER> is the prompt number of
         the output.
 
         Note that %edit is also available through the alias %ed.
 
         This is an example of creating a simple function inside the editor and
         then modifying it. First, start up the editor::
 
           In [1]: edit
           Editing... done. Executing edited code...
           Out[1]: 'def foo():\\n    print "foo() was defined in an editing
           session"\\n'
 
         We can then call the function foo()::
 
           In [2]: foo()
           foo() was defined in an editing session
 
         Now we edit foo.  IPython automatically loads the editor with the
         (temporary) file where foo() was previously defined::
 
           In [3]: edit foo
           Editing... done. Executing edited code...
 
         And if we call foo() again we get the modified version::
 
           In [4]: foo()
           foo() has now been changed!
 
         Here is an example of how to edit a code snippet successive
         times. First we call the editor::
 
           In [5]: edit
           Editing... done. Executing edited code...
           hello
           Out[5]: "print 'hello'\\n"
 
         Now we call it again with the previous output (stored in _)::
 
           In [6]: edit _
           Editing... done. Executing edited code...
           hello world
           Out[6]: "print 'hello world'\\n"
 
         Now we call it with the output #8 (stored in _8, also as Out[8])::
 
           In [7]: edit _8
           Editing... done. Executing edited code...
           hello again
           Out[7]: "print 'hello again'\\n"
 
 
         Changing the default editor hook:
 
         If you wish to write your own editor hook, you can put it in a
         configuration file which you load at startup time.  The default hook
         is defined in the IPython.core.hooks module, and you can use that as a
         starting example for further modifications.  That file also has
         general instructions on how to set a new hook for use once you've
         defined it."""
         opts,args = self.parse_options(parameter_s,'prxn:')
 
         try:
             filename, lineno, is_temp = self._find_edit_target(self.shell, 
                                                        args, opts, last_call)
         except MacroToEdit as e:
             self._edit_macro(args, e.args[0])
             return
         except InteractivelyDefined as e:
             print("Editing In[%i]" % e.index)
             args = str(e.index)
             filename, lineno, is_temp = self._find_edit_target(self.shell, 
                                                        args, opts, last_call)
         if filename is None:
             # nothing was found, warnings have already been issued,
             # just give up.
             return
 
         if is_temp:
             self._knowntemps.add(filename)
         elif (filename in self._knowntemps):
             is_temp = True
 
 
         # do actual editing here
         print('Editing...', end=' ')
         sys.stdout.flush()
         filepath = Path(filename)
         try:
             # Quote filenames that may have spaces in them when opening
             # the editor
             quoted = filename = str(filepath.absolute())
             if " " in quoted:
                 quoted = "'%s'" % quoted
             self.shell.hooks.editor(quoted, lineno)
         except TryNext:
             warn('Could not open editor')
             return
 
         # XXX TODO: should this be generalized for all string vars?
         # For now, this is special-cased to blocks created by cpaste
         if args.strip() == "pasted_block":
             self.shell.user_ns["pasted_block"] = filepath.read_text()
 
         if 'x' in opts:  # -x prevents actual execution
             print()
         else:
             print('done. Executing edited code...')
             with preserve_keys(self.shell.user_ns, '__file__'):
                 if not is_temp:
                     self.shell.user_ns['__file__'] = filename
                 if 'r' in opts:    # Untranslated IPython code
                     source = filepath.read_text()
                     self.shell.run_cell(source, store_history=False)
                 else:
                     self.shell.safe_execfile(filename, self.shell.user_ns,
                                              self.shell.user_ns)
 
         if is_temp:
             try:
                 return filepath.read_text()
             except IOError as msg:
                 if Path(msg.filename) == filepath:
                     warn('File not found. Did you forget to save?')
                     return
                 else:
                     self.shell.showtraceback()

IPython/core/magics/history.py

@@ -1,337 +1,338
 """Implementation of magic functions related to History.
 """
 #-----------------------------------------------------------------------------
 #  Copyright (c) 2012, IPython Development Team.
 #
 #  Distributed under the terms of the Modified BSD License.
 #
 #  The full license is in the file COPYING.txt, distributed with this software.
 #-----------------------------------------------------------------------------
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 
 # Stdlib
 import os
 import sys
 from io import open as io_open
 import fnmatch
 
 # Our own packages
 from IPython.core.error import StdinNotImplementedError
 from IPython.core.magic import Magics, magics_class, line_magic
 from IPython.core.magic_arguments import (argument, magic_arguments,
                                           parse_argstring)
 from IPython.testing.skipdoctest import skip_doctest
 from IPython.utils import io
 
 #-----------------------------------------------------------------------------
 # Magics class implementation
 #-----------------------------------------------------------------------------
 
 
 _unspecified = object()
 
 
 @magics_class
 class HistoryMagics(Magics):
 
     @magic_arguments()
     @argument(
         '-n', dest='print_nums', action='store_true', default=False,
         help="""
         print line numbers for each input.
         This feature is only available if numbered prompts are in use.
         """)
     @argument(
         '-o', dest='get_output', action='store_true', default=False,
         help="also print outputs for each input.")
     @argument(
         '-p', dest='pyprompts', action='store_true', default=False,
         help="""
         print classic '>>>' python prompts before each input.
         This is useful for making documentation, and in conjunction
         with -o, for producing doctest-ready output.
         """)
     @argument(
         '-t', dest='raw', action='store_false', default=True,
         help="""
         print the 'translated' history, as IPython understands it.
         IPython filters your input and converts it all into valid Python
         source before executing it (things like magics or aliases are turned
         into function calls, for example). With this option, you'll see the
         native history instead of the user-entered version: '%%cd /' will be
         seen as 'get_ipython().run_line_magic("cd", "/")' instead of '%%cd /'.
         """)
     @argument(
         '-f', dest='filename',
         help="""
         FILENAME: instead of printing the output to the screen, redirect
         it to the given file.  The file is always overwritten, though *when
         it can*, IPython asks for confirmation first. In particular, running
         the command 'history -f FILENAME' from the IPython Notebook
         interface will replace FILENAME even if it already exists *without*
         confirmation.
         """)
     @argument(
         '-g', dest='pattern', nargs='*', default=None,
         help="""
         treat the arg as a glob pattern to search for in (full) history.
         This includes the saved history (almost all commands ever written).
         The pattern may contain '?' to match one unknown character and '*'
         to match any number of unknown characters. Use '%%hist -g' to show
         full saved history (may be very long).
         """)
     @argument(
         '-l', dest='limit', type=int, nargs='?', default=_unspecified,
         help="""
         get the last n lines from all sessions. Specify n as a single
         arg, or the default is the last 10 lines.
         """)
     @argument(
         '-u', dest='unique', action='store_true',
         help="""
         when searching history using `-g`, show only unique history.
         """)
     @argument('range', nargs='*')
     @skip_doctest
     @line_magic
     def history(self, parameter_s = ''):
         """Print input history (_i<n> variables), with most recent last.
 
         By default, input history is printed without line numbers so it can be
         directly pasted into an editor. Use -n to show them.
 
         By default, all input history from the current session is displayed.
         Ranges of history can be indicated using the syntax:
         
         ``4``
             Line 4, current session
         ``4-6``
             Lines 4-6, current session
         ``243/1-5``
             Lines 1-5, session 243
         ``~2/7``
             Line 7, session 2 before current
         ``~8/1-~6/5``
             From the first line of 8 sessions ago, to the fifth line of 6
             sessions ago.
         
         Multiple ranges can be entered, separated by spaces
 
         The same syntax is used by %macro, %save, %edit, %rerun
 
         Examples
         --------
         ::
 
           In [6]: %history -n 4-6
           4:a = 12
           5:print a**2
           6:%history -n 4-6
 
         """
 
         args = parse_argstring(self.history, parameter_s)
 
         # For brevity
         history_manager = self.shell.history_manager
 
         def _format_lineno(session, line):
             """Helper function to format line numbers properly."""
             if session in (0, history_manager.session_number):
                 return str(line)
             return "%s/%s" % (session, line)
 
         # Check if output to specific file was requested.
         outfname = args.filename
         if not outfname:
             outfile = sys.stdout  # default
             # We don't want to close stdout at the end!
             close_at_end = False
         else:
+            outfname = os.path.expanduser(outfname)
             if os.path.exists(outfname):
                 try:
                     ans = io.ask_yes_no("File %r exists. Overwrite?" % outfname)
                 except StdinNotImplementedError:
                     ans = True
                 if not ans:
                     print('Aborting.')
                     return
                 print("Overwriting file.")
             outfile = io_open(outfname, 'w', encoding='utf-8')
             close_at_end = True
 
         print_nums = args.print_nums
         get_output = args.get_output
         pyprompts = args.pyprompts
         raw = args.raw
 
         pattern = None
         limit = None if args.limit is _unspecified else args.limit
 
         range_pattern = False
         if args.pattern is not None and not args.range:
             if args.pattern:
                 pattern = "*" + " ".join(args.pattern) + "*"
             else:
                 pattern = "*"
             hist = history_manager.search(pattern, raw=raw, output=get_output,
                                           n=limit, unique=args.unique)
             print_nums = True
         elif args.limit is not _unspecified:
             n = 10 if limit is None else limit
             hist = history_manager.get_tail(n, raw=raw, output=get_output)
         else:
             if args.pattern:
                 range_pattern = "*" + " ".join(args.pattern) + "*"
                 print_nums = True
             hist = history_manager.get_range_by_str(
                 " ".join(args.range), raw, get_output
             )
 
         # We could be displaying the entire history, so let's not try to pull
         # it into a list in memory. Anything that needs more space will just
         # misalign.
         width = 4
 
         for session, lineno, inline in hist:
             # Print user history with tabs expanded to 4 spaces.  The GUI
             # clients use hard tabs for easier usability in auto-indented code,
             # but we want to produce PEP-8 compliant history for safe pasting
             # into an editor.
             if get_output:
                 inline, output = inline
             if range_pattern:
                 if not fnmatch.fnmatch(inline, range_pattern):
                     continue
             inline = inline.expandtabs(4).rstrip()
 
             multiline = "\n" in inline
             line_sep = '\n' if multiline else ' '
             if print_nums:
                 print(u'%s:%s' % (_format_lineno(session, lineno).rjust(width),
                         line_sep),  file=outfile, end=u'')
             if pyprompts:
                 print(u">>> ", end=u"", file=outfile)
                 if multiline:
                     inline = "\n... ".join(inline.splitlines()) + "\n..."
             print(inline, file=outfile)
             if get_output and output:
                 print(output, file=outfile)
 
         if close_at_end:
             outfile.close()
 
     @line_magic
     def recall(self, arg):
         r"""Repeat a command, or get command to input line for editing.
 
         %recall and %rep are equivalent.
 
         - %recall (no arguments):
 
         Place a string version of last computation result (stored in the
         special '_' variable) to the next input prompt. Allows you to create
         elaborate command lines without using copy-paste::
 
              In[1]: l = ["hei", "vaan"]
              In[2]: "".join(l)
             Out[2]: heivaan
              In[3]: %recall
              In[4]: heivaan_ <== cursor blinking
 
         %recall 45
 
         Place history line 45 on the next input prompt. Use %hist to find
         out the number.
 
         %recall 1-4
 
         Combine the specified lines into one cell, and place it on the next
         input prompt. See %history for the slice syntax.
 
         %recall foo+bar
 
         If foo+bar can be evaluated in the user namespace, the result is
         placed at the next input prompt. Otherwise, the history is searched
         for lines which contain that substring, and the most recent one is
         placed at the next input prompt.
         """
         if not arg:                 # Last output
             self.shell.set_next_input(str(self.shell.user_ns["_"]))
             return
                                     # Get history range
         histlines = self.shell.history_manager.get_range_by_str(arg)
         cmd = "\n".join(x[2] for x in histlines)
         if cmd:
             self.shell.set_next_input(cmd.rstrip())
             return
 
         try:                        # Variable in user namespace
             cmd = str(eval(arg, self.shell.user_ns))
         except Exception:           # Search for term in history
             histlines = self.shell.history_manager.search("*"+arg+"*")
             for h in reversed([x[2] for x in histlines]):
                 if 'recall' in h or 'rep' in h:
                     continue
                 self.shell.set_next_input(h.rstrip())
                 return
         else:
             self.shell.set_next_input(cmd.rstrip())
             return
         print("Couldn't evaluate or find in history:", arg)
 
     @line_magic
     def rerun(self, parameter_s=''):
         """Re-run previous input
 
         By default, you can specify ranges of input history to be repeated
         (as with %history). With no arguments, it will repeat the last line.
 
         Options:
 
           -l <n> : Repeat the last n lines of input, not including the
           current command.
 
           -g foo : Repeat the most recent line which contains foo
         """
         opts, args = self.parse_options(parameter_s, 'l:g:', mode='string')
         if "l" in opts:         # Last n lines
             try:
                 n = int(opts["l"])
             except ValueError:
                 print("Number of lines must be an integer")
                 return
 
             if n == 0:
                 print("Requested 0 last lines - nothing to run")
                 return
             elif n < 0:
                 print("Number of lines to rerun cannot be negative")
                 return
 
             hist = self.shell.history_manager.get_tail(n)
         elif "g" in opts:       # Search
             p = "*"+opts['g']+"*"
             hist = list(self.shell.history_manager.search(p))
             for l in reversed(hist):
                 if "rerun" not in l[2]:
                     hist = [l]     # The last match which isn't a %rerun
                     break
             else:
                 hist = []          # No matches except %rerun
         elif args:              # Specify history ranges
             hist = self.shell.history_manager.get_range_by_str(args)
         else:                   # Last line
             hist = self.shell.history_manager.get_tail(1)
         hist = [x[2] for x in hist]
         if not hist:
             print("No lines in history match specification")
             return
         histlines = "\n".join(hist)
         print("=== Executing: ===")
         print(histlines)
         print("=== Output: ===")
         self.shell.run_cell("\n".join(hist), store_history=False)