Mini Shell
"""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(encoding="utf-8")
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(encoding="utf-8")
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(encoding="utf-8")
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(encoding="utf-8")
except IOError as msg:
if Path(msg.filename) == filepath:
warn('File not found. Did you forget to save?')
return
else:
self.shell.showtraceback()
Zerion Mini Shell 1.0