AliasCaller knows its own name

IPython/core/alias.py

@@ -1,220 +1,225 b''
 # 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 __builtin__
 import keyword
 import os
 import re
 import sys
 
 from IPython.config.configurable import Configurable
+from IPython.core.error import UsageError
 from IPython.core.splitinput import split_user_input
 
 from IPython.utils.traitlets import List, Instance
 from IPython.utils.warn import warn, 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 -i'), ('rm', 'rm -i'), ('cp', 'cp -i'),
                            ('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 /$'),
                           # things which are executable
                           ('lx', 'ls -F -o --color %l | grep ^-..x'),
                           ]
         else:
             # BSD, OSX, etc.
             ls_aliases = [('ls', 'ls -F -G'),
                           # long ls
                           ('ll', 'ls -F -l -G'),
                           # ls normal files only
                           ('lf', 'ls -F -l -G %l | grep ^-'),
                           # ls symbolic links
                           ('lk', 'ls -F -l -G %l | grep ^l'),
                           # directories or links to directories,
                           ('ldir', 'ls -F -G -l %l | grep /$'),
                           # 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 AliasCaller(object):
-    def __init__(self, shell, cmd):
+    def __init__(self, shell, name, cmd):
         self.shell = shell
+        self.name = name
         self.cmd = cmd
         self.nargs = cmd.count('%s')
         if (self.nargs > 0) and (cmd.find('%l') >= 0):
             raise InvalidAliasError('The %s and %l specifiers are mutually '
                                     'exclusive in alias definitions.')        
+    
+    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:
             # 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 AliasError('Alias <%s> requires %s arguments, %s given.' %
-                      (alias, nargs, len(args)))
+                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(), config=True)
     user_aliases = List(default_value=[], config=True)
     shell = Instance('IPython.core.interactiveshell.InteractiveShellABC')
 
     def __init__(self, shell=None, **kwargs):
         super(AliasManager, self).__init__(shell=shell, **kwargs)
         self.alias_table = {}
         self.init_exclusions()
         self.init_aliases()
 
     @property
     def aliases(self):
         linemagics = self.shell.magics_manager.magics['line']
         return [(n, func.cmd) for (n, func) in linemagics.items()
                             if isinstance(func, AliasCaller)]
 
     def init_exclusions(self):
         # set of things NOT to alias (keywords, builtins and some magics)
         no_alias = {'cd','popd','pushd','dhist','alias','unalias'}
         no_alias.update(set(keyword.kwlist))
         no_alias.update(set(__builtin__.__dict__.keys()))
         self.no_alias = no_alias
 
     def init_aliases(self):
         # Load default aliases
         for name, cmd in self.default_aliases:
             self.soft_define_alias(name, cmd)
 
         # Load user aliases
         for name, cmd in self.user_aliases:
             self.soft_define_alias(name, cmd)
     
     def clear_aliases(self):
         for name, cmd in self.aliases:
             self.undefine_alias(name)
 
     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.
         """
         self.validate_alias(name, cmd)
-        caller = AliasCaller(shell=self.shell, cmd=cmd)
+        caller = AliasCaller(shell=self.shell, name=name, cmd=cmd)
         self.shell.magics_manager.register_function(caller, magic_kind='line',
                                                     magic_name=name)
 
     def undefine_alias(self, name):
         linemagics = self.shell.magics_manager.magics['line']
         caller = linemagics.get(name, None)
         if isinstance(caller, AliasCaller):
             del linemagics[name]
         else:
             raise ValueError('%s is not an alias' % name)
 
     def validate_alias(self, name, cmd):
         """Validate an alias and return the its number of arguments."""
         if name in self.no_alias:
             raise InvalidAliasError("The name %s can't be aliased "
                                     "because it is a keyword or builtin." % name)
         if not (isinstance(cmd, basestring)):
             raise InvalidAliasError("An alias command must be a string, "
                                     "got: %r" % cmd)
         return True
     
     def retrieve_alias(self, name):
         """Retrieve the command to which an alias expands."""
         caller = self.shell.magics_manager.magics['line'].get(name, None)
         if isinstance(caller, AliasCaller):
             return caller.cmd
         else:
             raise ValueError('%s is not an alias' % name)