remove another py2 only test
remove another py2 only test

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"""Implementation of magic functions for interaction with the OS.
Note: this module is named 'osm' instead of 'os' to avoid a collision with the
from __future__ import print_function
# 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 io
import os
import re
import sys
from pprint import pformat
# Our own packages
from IPython.core import magic_arguments
from IPython.core import oinspect
from IPython.core import page
from IPython.core.alias import AliasError, Alias
from IPython.core.error import UsageError
from IPython.core.magic import (
Magics, compress_dhist, magics_class, line_magic, cell_magic, line_cell_magic
from IPython.testing.skipdoctest import skip_doctest
from IPython.utils.openpy import source_to_unicode
from IPython.utils.process import abbrev_cwd
from IPython.utils import py3compat
from IPython.utils.py3compat import unicode_type
from IPython.utils.terminal import set_term_title
# Magic implementation classes
class OSMagics(Magics):
"""Magics to interact with the underlying OS (shell-type functionality).
def alias(self, parameter_s=''):
"""Define an alias for a system command.
'%alias alias_name cmd' defines 'alias_name' as an alias for 'cmd'
Then, typing 'alias_name params' will execute the system command 'cmd
params' (from your underlying operating system).
Aliases have lower precedence than magic functions and Python normal
variables, so if 'foo' is both a Python variable and an alias, the
alias can not be executed until 'del foo' removes the Python variable.
You can use the %l specifier in an alias definition to represent the
whole line when the alias is called. For example::
In [2]: alias bracket echo "Input in brackets: <%l>"
In [3]: bracket hello world
Input in brackets: <hello world>
You can also define aliases with parameters using %s specifiers (one
per parameter)::
In [1]: alias parts echo first %s second %s
In [2]: %parts A B
first A second B
In [3]: %parts A
Incorrect number of arguments: 2 expected.
parts is an alias to: 'echo first %s second %s'
Note that %l and %s are mutually exclusive. You can only use one or
the other in your aliases.
Aliases expand Python variables just like system calls using ! or !!
do: all expressions prefixed with '$' get expanded. For details of
the semantic rules, see PEP-215: This is the library used by
IPython for variable expansion. If you want to access a true shell
variable, an extra $ is necessary to prevent its expansion by
In [6]: alias show echo
In [7]: PATH='A Python string'
In [8]: show $PATH
A Python string
In [9]: show $$PATH
You can use the alias facility to acess all of $PATH. See the %rehashx
function, which automatically creates aliases for the contents of your
If called with no parameters, %alias prints the current alias table."""
par = parameter_s.strip()
if not par:
aliases = sorted(
# stored ='stored_aliases', {} )
# for k, v in stored:
# atab.append(k, v[0])
print("Total number of aliases:", len(aliases))
return aliases
# Now try to define a new one
alias,cmd = par.split(None, 1)
except TypeError:
try:, cmd)
except AliasError as e:
# end magic_alias
def unalias(self, parameter_s=''):
"""Remove an alias"""
aname = parameter_s.strip()
except ValueError as e:
stored ='stored_aliases', {} )
if aname in stored:
print("Removing %stored alias",aname)
del stored[aname]['stored_aliases'] = stored
def rehashx(self, parameter_s=''):
"""Update the alias table with all executable files in $PATH.
rehashx explicitly checks that every entry in $PATH is a file
with execute access (os.X_OK).
Under Windows, it checks executability as a match against a
'|'-separated string of extensions, stored in the IPython config
variable win_exec_ext. This defaults to 'exe|com|bat'.
This function also resets the root module cache of module completer,
used on slow filesystems.
from IPython.core.alias import InvalidAliasError
# for the benefit of module completer in
path = [os.path.abspath(os.path.expanduser(p)) for p in
syscmdlist = []
# Now define isexec in a cross platform manner.
if == 'posix':
isexec = lambda fname:os.path.isfile(fname) and \
winext = os.environ['pathext'].replace(';','|').replace('.','')
except KeyError:
winext = 'exe|com|bat|py'
if 'py' not in winext:
winext += '|py'
execre = re.compile(r'(.*)\.(%s)$' % winext,re.IGNORECASE)
isexec = lambda fname:os.path.isfile(fname) and execre.match(fname)
savedir = py3compat.getcwd()
# Now walk the paths looking for executables to alias.
# write the whole loop for posix/Windows so we don't have an if in
# the innermost part
if == 'posix':
for pdir in path:
dirlist = os.listdir(pdir)
except OSError:
for ff in dirlist:
if isexec(ff):
# Removes dots from the name since ipython
# will assume names with dots to be python.
if not
ff.replace('.',''), ff)
except InvalidAliasError:
no_alias = Alias.blacklist
for pdir in path:
dirlist = os.listdir(pdir)
except OSError:
for ff in dirlist:
base, ext = os.path.splitext(ff)
if isexec(ff) and base.lower() not in no_alias:
if ext.lower() == '.exe':
ff = base
# Removes dots from the name since ipython
# will assume names with dots to be python.
base.lower().replace('.',''), ff)
except InvalidAliasError:
syscmdlist.append(ff)['syscmdlist'] = syscmdlist
def pwd(self, parameter_s=''):
"""Return the current working directory path.
In [9]: pwd
Out[9]: '/home/tsuser/sprint/ipython'
return py3compat.getcwd()
def cd(self, parameter_s=''):
"""Change the current working directory.
This command automatically maintains an internal list of directories
you visit during your IPython session, in the variable _dh. The
command %dhist shows this history nicely formatted. You can also
do 'cd -<tab>' to see directory history conveniently.
cd 'dir': changes to directory 'dir'.
cd -: changes to the last visited directory.
cd -<n>: changes to the n-th directory in the directory history.
cd --foo: change to directory that matches 'foo' in history
cd -b <bookmark_name>: jump to a bookmark set by %bookmark
(note: cd <bookmark_name> is enough if there is no
directory <bookmark_name>, but a bookmark with the name exists.)
'cd -b <tab>' allows you to tab-complete bookmark names.
-q: quiet. Do not print the working directory after the cd command is
executed. By default IPython's cd command does print this directory,
since the default prompts do not display path information.
Note that !cd doesn't work for this purpose because the shell where
!command runs is immediately discarded after executing 'command'.
In [10]: cd parent/child
oldcwd = py3compat.getcwd()
numcd = re.match(r'(-)(\d+)$',parameter_s)
# jump in directory history by number
if numcd:
nn = int(
ps =['_dh'][nn]
except IndexError:
print('The requested directory does not exist in history.')
opts = {}
elif parameter_s.startswith('--'):
ps = None
fallback = None
pat = parameter_s[2:]
dh =['_dh']
# first search only by basename (last component)
for ent in reversed(dh):
if pat in os.path.basename(ent) and os.path.isdir(ent):
ps = ent
if fallback is None and pat in ent and os.path.isdir(ent):
fallback = ent
# if we have no last part match, pick the first full path match
if ps is None:
ps = fallback
if ps is None:
print("No matching entry in directory history")
opts = {}
opts, ps = self.parse_options(parameter_s, 'qb', mode='string')
# jump to previous
if ps == '-':
ps =['_dh'][-2]
except IndexError:
raise UsageError('%cd -: No previous directory to change to.')
# jump to bookmark if needed
if not os.path.isdir(ps) or 'b' in opts:
bkms ='bookmarks', {})
if ps in bkms:
target = bkms[ps]
print('(bookmark:%s) -> %s' % (ps, target))
ps = target
if 'b' in opts:
raise UsageError("Bookmark '%s' not found. "
"Use '%%bookmark -l' to see your bookmarks." % ps)
# at this point ps should point to the target dir
if ps:
if hasattr(, 'term_title') and
set_term_title('IPython: ' + abbrev_cwd())
except OSError:
cwd = py3compat.getcwd()
dhist =['_dh']
if oldcwd != cwd:
dhist.append(cwd)['dhist'] = compress_dhist(dhist)[-100:]
if hasattr(, 'term_title') and
set_term_title('IPython: ' + '~')
cwd = py3compat.getcwd()
dhist =['_dh']
if oldcwd != cwd:
dhist.append(cwd)['dhist'] = compress_dhist(dhist)[-100:]
if not 'q' in opts and['_dh']:
def env(self, parameter_s=''):
"""Get, set, or list environment variables.
%env: lists all environment variables/values
%env var: get value for var
%env var val: set value for var
%env var=val: set value for var
%env var=$val: set value for var, using python expansion if possible
if parameter_s.strip():
split = '=' if '=' in parameter_s else ' '
bits = parameter_s.split(split)
if len(bits) == 1:
key = parameter_s.strip()
if key in os.environ:
return os.environ[key]
err = "Environment does not have key: {0}".format(key)
raise UsageError(err)
if len(bits) > 1:
return self.set_env(parameter_s)
return dict(os.environ)
def set_env(self, parameter_s):
"""Set environment variables. Assumptions are that either "val" is a
name in the user namespace, or val is something that evaluates to a
%set_env var val: set value for var
%set_env var=val: set value for var
%set_env var=$val: set value for var, using python expansion if possible
split = '=' if '=' in parameter_s else ' '
bits = parameter_s.split(split, 1)
if not parameter_s.strip() or len(bits)<2:
raise UsageError("usage is 'set_env var=val'")
var = bits[0].strip()
val = bits[1].strip()
if re.match(r'.*\s.*', var):
# an environment variable with whitespace is almost certainly
# not what the user intended. what's more likely is the wrong
# split was chosen, ie for "set_env cmd_args A=B", we chose
# '=' for the split and should have chosen ' '. to get around
# this, users should just assign directly to os.environ or use
# standard magic {var} expansion.
err = "refusing to set env var with whitespace: '{0}'"
err = err.format(val)
raise UsageError(err)
os.environ[py3compat.cast_bytes_py2(var)] = py3compat.cast_bytes_py2(val)
print('env: {0}={1}'.format(var,val))
def pushd(self, parameter_s=''):
"""Place the current dir on stack and change directory.
%pushd ['dirname']
dir_s =
tgt = os.path.expanduser(parameter_s)
cwd = py3compat.getcwd().replace(,'~')
if tgt:
def popd(self, parameter_s=''):
"""Change to directory popped off the top of the stack.
if not
raise UsageError("%popd on empty stack")
top =
print("popd ->",top)
def dirs(self, parameter_s=''):
"""Return the current directory stack."""
def dhist(self, parameter_s=''):
"""Print your history of visited directories.
%dhist -> print full history\\
%dhist n -> print last n entries only\\
%dhist n1 n2 -> print entries between n1 and n2 (n2 not included)\\
This history is automatically maintained by the %cd command, and
always available as the global list variable _dh. You can use %cd -<n>
to go to directory number <n>.
Note that most of time, you should view directory history by entering
cd -<TAB>.
dh =['_dh']
if parameter_s:
args = map(int,parameter_s.split())
if len(args) == 1:
ini,fin = max(len(dh)-(args[0]),0),len(dh)
elif len(args) == 2:
ini,fin = args
fin = min(fin, len(dh))
ini,fin = 0,len(dh)
print('Directory history (kept in _dh)')
for i in range(ini, fin):
print("%d: %s" % (i, dh[i]))
def sc(self, parameter_s=''):
"""Shell capture - run shell command and capture output (DEPRECATED use !).
DEPRECATED. Suboptimal, retained for backwards compatibility.
You should use the form 'var = !command' instead. Example:
"%sc -l myfiles = ls ~" should now be written as
"myfiles = !ls ~"
myfiles.s, myfiles.l and myfiles.n still apply as documented
%sc [options] varname=command
IPython will run the given command using commands.getoutput(), and
will then update the user's interactive namespace with a variable
called varname, containing the value of the call. Your command can
contain shell wildcards, pipes, etc.
The '=' sign in the syntax is mandatory, and the variable name you
supply must follow Python's standard conventions for valid names.
(A special format without variable name exists for internal use)
-l: list output. Split the output on newlines into a list before
assigning it to the given variable. By default the output is stored
as a single string.
-v: verbose. Print the contents of the variable.
In most cases you should not need to split as a list, because the
returned value is a special type of string which can automatically
provide its contents either as a list (split on newlines) or as a
space-separated string. These are convenient, respectively, either
for sequential processing or to be passed to a shell command.
For example::
# Capture into variable a
In [1]: sc a=ls *py
# a is a string with embedded newlines
In [2]: a
Out[2]: '\\'
# which can be seen as a list:
In [3]: a.l
Out[3]: ['', '']
# or as a whitespace-separated string:
In [4]: a.s
Out[4]: ''
# a.s is useful to pass as a single command line:
In [5]: !wc -l $a.s
276 total
# while the list form is useful to loop over:
In [6]: for f in a.l:
...: !wc -l $f
Similarly, the lists returned by the -l option are also special, in
the sense that you can equally invoke the .s attribute on them to
automatically get a whitespace-separated string from their contents::
In [7]: sc -l b=ls *py
In [8]: b
Out[8]: ['', '']
In [9]: b.s
Out[9]: ''
In summary, both the lists and strings used for output capture have
the following special attributes::
.l (or .list) : value as list.
.n (or .nlstr): value as newline-separated string.
.s (or .spstr): value as space-separated string.
opts,args = self.parse_options(parameter_s, 'lv')
# Try to get a variable name and command to run
# the variable name must be obtained from the parse_options
# output, which uses shlex.split to strip options out.
var,_ = args.split('=', 1)
var = var.strip()
# But the command has to be extracted from the original input
# parameter_s, not on what parse_options returns, to avoid the
# quote stripping which shlex.split performs on it.
_,cmd = parameter_s.split('=', 1)
except ValueError:
var,cmd = '',''
# If all looks ok, proceed
split = 'l' in opts
out =, split=split)
if 'v' in opts:
print('%s ==\n%s' % (var, pformat(out)))
if var:{var:out})
return out
def sx(self, line='', cell=None):
"""Shell execute - run shell command and capture output (!! is short-hand).
%sx command
IPython will run the given command using commands.getoutput(), and
return the result formatted as a list (split on '\\n'). Since the
output is _returned_, it will be stored in ipython's regular output
cache Out[N] and in the '_N' automatic variables.
1) If an input line begins with '!!', then %sx is automatically
invoked. That is, while::
causes ipython to simply issue system('ls'), typing::
is a shorthand equivalent to::
%sx ls
2) %sx differs from %sc in that %sx automatically splits into a list,
like '%sc -l'. The reason for this is to make it as easy as possible
to process line-oriented shell output via further python commands.
%sc is meant to provide much finer control, but requires more
3) Just like %sc -l, this is a list with special attributes:
.l (or .list) : value as list.
.n (or .nlstr): value as newline-separated string.
.s (or .spstr): value as whitespace-separated string.
This is very useful when trying to use such lists as arguments to
system commands."""
if cell is None:
# line magic
opts,args = self.parse_options(line, '', 'out=')
output =
out_name = opts.get('out', opts.get('o'))
if out_name:[out_name] = output
return output
system = line_cell_magic('system')(sx)
bang = cell_magic('!')(sx)
def bookmark(self, parameter_s=''):
"""Manage IPython's bookmark system.
%bookmark <name> - set bookmark to current dir
%bookmark <name> <dir> - set bookmark to <dir>
%bookmark -l - list all bookmarks
%bookmark -d <name> - remove bookmark
%bookmark -r - remove all bookmarks
You can later on access a bookmarked folder with::
%cd -b <name>
or simply '%cd <name>' if there is no directory called <name> AND
there is such a bookmark defined.
Your bookmarks persist through IPython sessions, but they are
associated with each profile."""
opts,args = self.parse_options(parameter_s,'drl',mode='list')
if len(args) > 2:
raise UsageError("%bookmark: too many arguments")
bkms ='bookmarks',{})
if 'd' in opts:
todel = args[0]
except IndexError:
raise UsageError(
"%bookmark -d: must provide a bookmark to delete")
del bkms[todel]
except KeyError:
raise UsageError(
"%%bookmark -d: Can't delete bookmark '%s'" % todel)
elif 'r' in opts:
bkms = {}
elif 'l' in opts:
bks = sorted(bkms)
if bks:
size = max(map(len, bks))
size = 0
fmt = '%-'+str(size)+'s -> %s'
print('Current bookmarks:')
for bk in bks:
print(fmt % (bk, bkms[bk]))
if not args:
raise UsageError("%bookmark: You must specify the bookmark name")
elif len(args)==1:
bkms[args[0]] = py3compat.getcwd()
elif len(args)==2:
bkms[args[0]] = args[1]['bookmarks'] = bkms
def pycat(self, parameter_s=''):
"""Show a syntax-highlighted file through a pager.
This magic is similar to the cat utility, but it will assume the file
to be Python source and will show it with syntax highlighting.
This magic command can either take a local filename, an url,
an history range (see %history) or a macro as argument ::
%pycat 7-27
%pycat myMacro
if not parameter_s:
raise UsageError('Missing filename, URL, input history range, '
'or macro.')
try :
cont =, skip_encoding_cookie=False)
except (ValueError, IOError):
print("Error: no such file, variable, URL, history range or macro")
'-a', '--append', action='store_true', default=False,
help='Append contents of the cell to an existing file. '
'The file will be created if it does not exist.'
'filename', type=unicode_type,
help='file to write'
def writefile(self, line, cell):
"""Write the contents of the cell to a file.
The file will be overwritten unless the -a (--append) flag is specified.
args = magic_arguments.parse_argstring(self.writefile, line)
filename = os.path.expanduser(args.filename)
if os.path.exists(filename):
if args.append:
print("Appending to %s" % filename)
print("Overwriting %s" % filename)
print("Writing %s" % filename)
mode = 'a' if args.append else 'w'
with, mode, encoding='utf-8') as f: