Mini Shell
# encoding: utf-8
"""
System command aliases.
Authors:
* Fernando Perez
* Brian Granger
"""
#-----------------------------------------------------------------------------
# Copyright (C) 2008-2011 The IPython Development Team
#
# Distributed under the terms of the BSD License.
#
# The full license is in the file COPYING.txt, distributed with this software.
#-----------------------------------------------------------------------------
#-----------------------------------------------------------------------------
# Imports
#-----------------------------------------------------------------------------
import os
import re
import sys
from traitlets.config.configurable import Configurable
from .error import UsageError
from traitlets import List, Instance
from logging import error
#-----------------------------------------------------------------------------
# Utilities
#-----------------------------------------------------------------------------
# This is used as the pattern for calls to split_user_input.
shell_line_split = re.compile(r'^(\s*)()(\S+)(.*$)')
def default_aliases():
"""Return list of shell aliases to auto-define.
"""
# Note: the aliases defined here should be safe to use on a kernel
# regardless of what frontend it is attached to. Frontends that use a
# kernel in-process can define additional aliases that will only work in
# their case. For example, things like 'less' or 'clear' that manipulate
# the terminal should NOT be declared here, as they will only work if the
# kernel is running inside a true terminal, and not over the network.
if os.name == 'posix':
default_aliases = [('mkdir', 'mkdir'), ('rmdir', 'rmdir'),
('mv', 'mv'), ('rm', 'rm'), ('cp', 'cp'),
('cat', 'cat'),
]
# Useful set of ls aliases. The GNU and BSD options are a little
# different, so we make aliases that provide as similar as possible
# behavior in ipython, by passing the right flags for each platform
if sys.platform.startswith('linux'):
ls_aliases = [('ls', 'ls -F --color'),
# long ls
('ll', 'ls -F -o --color'),
# ls normal files only
('lf', 'ls -F -o --color %l | grep ^-'),
# ls symbolic links
('lk', 'ls -F -o --color %l | grep ^l'),
# directories or links to directories,
('ldir', 'ls -F -o --color %l | grep /$'),
# things which are executable
('lx', 'ls -F -o --color %l | grep ^-..x'),
]
elif sys.platform.startswith('openbsd') or sys.platform.startswith('netbsd'):
# OpenBSD, NetBSD. The ls implementation on these platforms do not support
# the -G switch and lack the ability to use colorized output.
ls_aliases = [('ls', 'ls -F'),
# long ls
('ll', 'ls -F -l'),
# ls normal files only
('lf', 'ls -F -l %l | grep ^-'),
# ls symbolic links
('lk', 'ls -F -l %l | grep ^l'),
# directories or links to directories,
('ldir', 'ls -F -l %l | grep /$'),
# things which are executable
('lx', 'ls -F -l %l | grep ^-..x'),
]
else:
# BSD, OSX, etc.
ls_aliases = [('ls', 'ls -F -G'),
# long ls
('ll', 'ls -F -l -G'),
# ls normal files only
('lf', 'ls -F -l -G %l | grep ^-'),
# ls symbolic links
('lk', 'ls -F -l -G %l | grep ^l'),
# directories or links to directories,
('ldir', 'ls -F -G -l %l | grep /$'),
# things which are executable
('lx', 'ls -F -l -G %l | grep ^-..x'),
]
default_aliases = default_aliases + ls_aliases
elif os.name in ['nt', 'dos']:
default_aliases = [('ls', 'dir /on'),
('ddir', 'dir /ad /on'), ('ldir', 'dir /ad /on'),
('mkdir', 'mkdir'), ('rmdir', 'rmdir'),
('echo', 'echo'), ('ren', 'ren'), ('copy', 'copy'),
]
else:
default_aliases = []
return default_aliases
class AliasError(Exception):
pass
class InvalidAliasError(AliasError):
pass
class Alias(object):
"""Callable object storing the details of one alias.
Instances are registered as magic functions to allow use of aliases.
"""
# Prepare blacklist
blacklist = {'cd','popd','pushd','dhist','alias','unalias'}
def __init__(self, shell, name, cmd):
self.shell = shell
self.name = name
self.cmd = cmd
self.__doc__ = "Alias for `!{}`".format(cmd)
self.nargs = self.validate()
def validate(self):
"""Validate the alias, and return the number of arguments."""
if self.name in self.blacklist:
raise InvalidAliasError("The name %s can't be aliased "
"because it is a keyword or builtin." % self.name)
try:
caller = self.shell.magics_manager.magics['line'][self.name]
except KeyError:
pass
else:
if not isinstance(caller, Alias):
raise InvalidAliasError("The name %s can't be aliased "
"because it is another magic command." % self.name)
if not (isinstance(self.cmd, str)):
raise InvalidAliasError("An alias command must be a string, "
"got: %r" % self.cmd)
nargs = self.cmd.count('%s') - self.cmd.count('%%s')
if (nargs > 0) and (self.cmd.find('%l') >= 0):
raise InvalidAliasError('The %s and %l specifiers are mutually '
'exclusive in alias definitions.')
return nargs
def __repr__(self):
return "<alias {} for {!r}>".format(self.name, self.cmd)
def __call__(self, rest=''):
cmd = self.cmd
nargs = self.nargs
# Expand the %l special to be the user's input line
if cmd.find('%l') >= 0:
cmd = cmd.replace('%l', rest)
rest = ''
if nargs==0:
if cmd.find('%%s') >= 1:
cmd = cmd.replace('%%s', '%s')
# Simple, argument-less aliases
cmd = '%s %s' % (cmd, rest)
else:
# Handle aliases with positional arguments
args = rest.split(None, nargs)
if len(args) < nargs:
raise UsageError('Alias <%s> requires %s arguments, %s given.' %
(self.name, nargs, len(args)))
cmd = '%s %s' % (cmd % tuple(args[:nargs]),' '.join(args[nargs:]))
self.shell.system(cmd)
#-----------------------------------------------------------------------------
# Main AliasManager class
#-----------------------------------------------------------------------------
class AliasManager(Configurable):
default_aliases = List(default_aliases()).tag(config=True)
user_aliases = List(default_value=[]).tag(config=True)
shell = Instance('IPython.core.interactiveshell.InteractiveShellABC', allow_none=True)
def __init__(self, shell=None, **kwargs):
super(AliasManager, self).__init__(shell=shell, **kwargs)
# For convenient access
self.linemagics = self.shell.magics_manager.magics['line']
self.init_aliases()
def init_aliases(self):
# Load default & user aliases
for name, cmd in self.default_aliases + self.user_aliases:
if cmd.startswith('ls ') and self.shell.colors == 'NoColor':
cmd = cmd.replace(' --color', '')
self.soft_define_alias(name, cmd)
@property
def aliases(self):
return [(n, func.cmd) for (n, func) in self.linemagics.items()
if isinstance(func, Alias)]
def soft_define_alias(self, name, cmd):
"""Define an alias, but don't raise on an AliasError."""
try:
self.define_alias(name, cmd)
except AliasError as e:
error("Invalid alias: %s" % e)
def define_alias(self, name, cmd):
"""Define a new alias after validating it.
This will raise an :exc:`AliasError` if there are validation
problems.
"""
caller = Alias(shell=self.shell, name=name, cmd=cmd)
self.shell.magics_manager.register_function(caller, magic_kind='line',
magic_name=name)
def get_alias(self, name):
"""Return an alias, or None if no alias by that name exists."""
aname = self.linemagics.get(name, None)
return aname if isinstance(aname, Alias) else None
def is_alias(self, name):
"""Return whether or not a given name has been defined as an alias"""
return self.get_alias(name) is not None
def undefine_alias(self, name):
if self.is_alias(name):
del self.linemagics[name]
else:
raise ValueError('%s is not an alias' % name)
def clear_aliases(self):
for name, cmd in self.aliases:
self.undefine_alias(name)
def retrieve_alias(self, name):
"""Retrieve the command to which an alias expands."""
caller = self.get_alias(name)
if caller:
return caller.cmd
else:
raise ValueError('%s is not an alias' % name)
Zerion Mini Shell 1.0