Update terminal-only magics to new API.

IPython/frontend/terminal/interactiveshell.py

@@ -1,683 +1,676 b''
 # -*- coding: utf-8 -*-
 """Subclass of InteractiveShell for terminal based frontends."""
 
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2001 Janko Hauser <[e-mail]>
 #  Copyright (C) 2001-2007 Fernando Perez. <[e-mail]>
 #  Copyright (C) 2008-2011  The IPython Development Team
 #
 #  Distributed under the terms of the BSD License.  The full license is in
 #  the file COPYING, distributed as part of this software.
 #-----------------------------------------------------------------------------
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 
-import __builtin__
 import bdb
 import os
 import re
 import sys
 import textwrap
 
-try:
     from contextlib import nested
-except:
-    from IPython.utils.nested_context import nested
 
 from IPython.core.error import TryNext, UsageError
 from IPython.core.usage import interactive_usage, default_banner
 from IPython.core.interactiveshell import InteractiveShell, InteractiveShellABC
-from IPython.core.pylabtools import pylab_activate
+from IPython.core.magic import Magics, register_magics, line_magic
 from IPython.testing.skipdoctest import skip_doctest
 from IPython.utils.encoding import get_stream_enc
 from IPython.utils import py3compat
 from IPython.utils.terminal import toggle_set_term_title, set_term_title
 from IPython.utils.process import abbrev_cwd
 from IPython.utils.warn import warn, error
 from IPython.utils.text import num_ini_spaces, SList
 from IPython.utils.traitlets import Integer, CBool, Unicode
 
 #-----------------------------------------------------------------------------
 # Utilities
 #-----------------------------------------------------------------------------
 
 def get_default_editor():
     try:
         ed = os.environ['EDITOR']
     except KeyError:
         if os.name == 'posix':
             ed = 'vi'  # the only one guaranteed to be there!
         else:
             ed = 'notepad' # same in Windows!
     return ed
 
 
 def get_pasted_lines(sentinel, l_input=py3compat.input):
     """ Yield pasted lines until the user enters the given sentinel value.
     """
     print "Pasting code; enter '%s' alone on the line to stop or use Ctrl-D." \
           % sentinel
     while True:
         try:
             l = l_input(':')
             if l == sentinel:
                 return
             else:
                 yield l
         except EOFError:
             print '<EOF>'
             return
 
 
 def strip_email_quotes(raw_lines):
     """ Strip email quotation marks at the beginning of each line.
 
     We don't do any more input transofrmations here because the main shell's
     prefiltering handles other cases.
     """
     lines = [re.sub(r'^\s*(\s?>)+', '', l) for l in raw_lines]
     return '\n'.join(lines) + '\n'
 
 
 # These two functions are needed by the %paste/%cpaste magics.  In practice
 # they are basically methods (they take the shell as their first argument), but
 # we leave them as standalone functions because eventually the magics
 # themselves will become separate objects altogether.  At that point, the
 # magics will have access to the shell object, and these functions can be made
 # methods of the magic object, but not of the shell.
 
 def store_or_execute(shell, block, name):
     """ Execute a block, or store it in a variable, per the user's request.
     """
     # Dedent and prefilter so what we store matches what is executed by
     # run_cell.
     b = shell.prefilter(textwrap.dedent(block))
 
     if name:
         # If storing it for further editing, run the prefilter on it
         shell.user_ns[name] = SList(b.splitlines())
         print "Block assigned to '%s'" % name
     else:
         shell.user_ns['pasted_block'] = b
         shell.run_cell(b)
 
 
 def rerun_pasted(shell, name='pasted_block'):
     """ Rerun a previously pasted command.
     """
     b = shell.user_ns.get(name)
 
     # Sanity checks
     if b is None:
         raise UsageError('No previous pasted block available')
     if not isinstance(b, basestring):
         raise UsageError(
             "Variable 'pasted_block' is not a string, can't execute")
 
     print "Re-executing '%s...' (%d chars)"% (b.split('\n',1)[0], len(b))
     shell.run_cell(b)
 
 
 #------------------------------------------------------------------------
 # Terminal-specific magics
 #------------------------------------------------------------------------
 
-def magic_autoindent(self, parameter_s = ''):
+@register_magics
+class TerminalMagics(Magics):
+
+    @line_magic
+    def autoindent(self, parameter_s = ''):
     """Toggle autoindent on/off (if available)."""
 
     self.shell.set_autoindent()
     print "Automatic indentation is:",['OFF','ON'][self.shell.autoindent]
 
 @skip_doctest
-def magic_cpaste(self, parameter_s=''):
+    @line_magic
+    def cpaste(self, parameter_s=''):
     """Paste & execute a pre-formatted code block from clipboard.
 
     You must terminate the block with '--' (two minus-signs) or Ctrl-D
     alone on the line. You can also provide your own sentinel with '%paste
     -s %%' ('%%' is the new sentinel for this operation)
 
     The block is dedented prior to execution to enable execution of method
     definitions. '>' and '+' characters at the beginning of a line are
     ignored, to allow pasting directly from e-mails, diff files and
     doctests (the '...' continuation prompt is also stripped).  The
     executed block is also assigned to variable named 'pasted_block' for
     later editing with '%edit pasted_block'.
 
     You can also pass a variable name as an argument, e.g. '%cpaste foo'.
     This assigns the pasted block to variable 'foo' as string, without
     dedenting or executing it (preceding >>> and + is still stripped)
 
     '%cpaste -r' re-executes the block previously entered by cpaste.
 
     Do not be alarmed by garbled output on Windows (it's a readline bug).
     Just press enter and type -- (and press enter again) and the block
     will be what was just pasted.
 
     IPython statements (magics, shell escapes) are not supported (yet).
 
     See also
     --------
     paste: automatically pull code from clipboard.
 
     Examples
     --------
     ::
 
       In [8]: %cpaste
       Pasting code; enter '--' alone on the line to stop.
       :>>> a = ["world!", "Hello"]
       :>>> print " ".join(sorted(a))
       :--
       Hello world!
     """
 
     opts, name = self.parse_options(parameter_s, 'rs:', mode='string')
     if 'r' in opts:
         rerun_pasted(self.shell)
         return
 
     sentinel = opts.get('s', '--')
     block = strip_email_quotes(get_pasted_lines(sentinel))
     store_or_execute(self.shell, block, name)
 
-
-def magic_paste(self, parameter_s=''):
+    @line_magic
+    def paste(self, parameter_s=''):
     """Paste & execute a pre-formatted code block from clipboard.
 
     The text is pulled directly from the clipboard without user
     intervention and printed back on the screen before execution (unless
     the -q flag is given to force quiet mode).
 
     The block is dedented prior to execution to enable execution of method
     definitions. '>' and '+' characters at the beginning of a line are
     ignored, to allow pasting directly from e-mails, diff files and
     doctests (the '...' continuation prompt is also stripped).  The
     executed block is also assigned to variable named 'pasted_block' for
     later editing with '%edit pasted_block'.
 
     You can also pass a variable name as an argument, e.g. '%paste foo'.
     This assigns the pasted block to variable 'foo' as string, without
     dedenting or executing it (preceding >>> and + is still stripped)
 
     Options
     -------
 
       -r: re-executes the block previously entered by cpaste.
 
       -q: quiet mode: do not echo the pasted text back to the terminal.
 
     IPython statements (magics, shell escapes) are not supported (yet).
 
     See also
     --------
     cpaste: manually paste code into terminal until you mark its end.
     """
     opts, name = self.parse_options(parameter_s, 'rq', mode='string')
     if 'r' in opts:
         rerun_pasted(self.shell)
         return
     try:
         text = self.shell.hooks.clipboard_get()
         block = strip_email_quotes(text.splitlines())
     except TryNext as clipboard_exc:
         message = getattr(clipboard_exc, 'args')
         if message:
             error(message[0])
         else:
             error('Could not get text from the clipboard.')
         return
 
     # By default, echo back to terminal unless quiet mode is requested
     if 'q' not in opts:
         write = self.shell.write
         write(self.shell.pycolorize(block))
         if not block.endswith('\n'):
             write('\n')
         write("## -- End pasted text --\n")
 
     store_or_execute(self.shell, block, name)
 
-
 # Class-level: add a '%cls' magic only on Windows
 if sys.platform == 'win32':
-    def magic_cls(self, s):
+        @line_magic
+        def cls(self, s):
         """Clear screen.
         """
         os.system("cls")
 
 #-----------------------------------------------------------------------------
 # Main class
 #-----------------------------------------------------------------------------
 
 class TerminalInteractiveShell(InteractiveShell):
 
     autoedit_syntax = CBool(False, config=True,
         help="auto editing of files with syntax errors.")
     banner = Unicode('')
     banner1 = Unicode(default_banner, config=True,
         help="""The part of the banner to be printed before the profile"""
     )
     banner2 = Unicode('', config=True,
         help="""The part of the banner to be printed after the profile"""
     )
     confirm_exit = CBool(True, config=True,
         help="""
         Set to confirm when you try to exit IPython with an EOF (Control-D
         in Unix, Control-Z/Enter in Windows). By typing 'exit' or 'quit',
         you can force a direct exit without any confirmation.""",
     )
     # This display_banner only controls whether or not self.show_banner()
     # is called when mainloop/interact are called.  The default is False
     # because for the terminal based application, the banner behavior
     # is controlled by Global.display_banner, which IPythonApp looks at
     # to determine if *it* should call show_banner() by hand or not.
     display_banner = CBool(False) # This isn't configurable!
     embedded = CBool(False)
     embedded_active = CBool(False)
     editor = Unicode(get_default_editor(), config=True,
         help="Set the editor used by IPython (default to $EDITOR/vi/notepad)."
     )
     pager = Unicode('less', config=True,
         help="The shell program to be used for paging.")
 
     screen_length = Integer(0, config=True,
         help=
         """Number of lines of your screen, used to control printing of very
         long strings.  Strings longer than this number of lines will be sent
         through a pager instead of directly printed.  The default value for
         this is 0, which means IPython will auto-detect your screen size every
         time it needs to print certain potentially long strings (this doesn't
         change the behavior of the 'print' keyword, it's only triggered
         internally). If for some reason this isn't working well (it needs
         curses support), specify it yourself. Otherwise don't change the
         default.""",
     )
     term_title = CBool(False, config=True,
         help="Enable auto setting the terminal title."
     )
 
     # In the terminal, GUI control is done via PyOS_InputHook
     from IPython.lib.inputhook import enable_gui
     enable_gui = staticmethod(enable_gui)
     
     def __init__(self, config=None, ipython_dir=None, profile_dir=None,
                  user_ns=None, user_module=None, custom_exceptions=((),None),
                  usage=None, banner1=None, banner2=None, display_banner=None):
 
         super(TerminalInteractiveShell, self).__init__(
             config=config, profile_dir=profile_dir, user_ns=user_ns,
             user_module=user_module, custom_exceptions=custom_exceptions
         )
         # use os.system instead of utils.process.system by default,
         # because piped system doesn't make sense in the Terminal:
         self.system = self.system_raw
 
         self.init_term_title()
         self.init_usage(usage)
         self.init_banner(banner1, banner2, display_banner)
 
     #-------------------------------------------------------------------------
     # Things related to the terminal
     #-------------------------------------------------------------------------
 
     @property
     def usable_screen_length(self):
         if self.screen_length == 0:
             return 0
         else:
             num_lines_bot = self.separate_in.count('\n')+1
             return self.screen_length - num_lines_bot
 
     def init_term_title(self):
         # Enable or disable the terminal title.
         if self.term_title:
             toggle_set_term_title(True)
             set_term_title('IPython: ' + abbrev_cwd())
         else:
             toggle_set_term_title(False)
 
     #-------------------------------------------------------------------------
     # Things related to aliases
     #-------------------------------------------------------------------------
 
     def init_alias(self):
         # The parent class defines aliases that can be safely used with any
         # frontend.
         super(TerminalInteractiveShell, self).init_alias()
 
         # Now define aliases that only make sense on the terminal, because they
         # need direct access to the console in a way that we can't emulate in
         # GUI or web frontend
         if os.name == 'posix':
             aliases = [('clear', 'clear'), ('more', 'more'), ('less', 'less'),
                        ('man', 'man')]
         elif os.name == 'nt':
             aliases = [('cls', 'cls')]
 
 
         for name, cmd in aliases:
             self.alias_manager.define_alias(name, cmd)
 
     #-------------------------------------------------------------------------
     # Things related to the banner and usage
     #-------------------------------------------------------------------------
 
     def _banner1_changed(self):
         self.compute_banner()
 
     def _banner2_changed(self):
         self.compute_banner()
 
     def _term_title_changed(self, name, new_value):
         self.init_term_title()
 
     def init_banner(self, banner1, banner2, display_banner):
         if banner1 is not None:
             self.banner1 = banner1
         if banner2 is not None:
             self.banner2 = banner2
         if display_banner is not None:
             self.display_banner = display_banner
         self.compute_banner()
 
     def show_banner(self, banner=None):
         if banner is None:
             banner = self.banner
         self.write(banner)
 
     def compute_banner(self):
         self.banner = self.banner1
         if self.profile and self.profile != 'default':
             self.banner += '\nIPython profile: %s\n' % self.profile
         if self.banner2:
             self.banner += '\n' + self.banner2
 
     def init_usage(self, usage=None):
         if usage is None:
             self.usage = interactive_usage
         else:
             self.usage = usage
 
     #-------------------------------------------------------------------------
     # Mainloop and code execution logic
     #-------------------------------------------------------------------------
 
     def mainloop(self, display_banner=None):
         """Start the mainloop.
 
         If an optional banner argument is given, it will override the
         internally created default banner.
         """
 
         with nested(self.builtin_trap, self.display_trap):
 
             while 1:
                 try:
                     self.interact(display_banner=display_banner)
                     #self.interact_with_readline()
                     # XXX for testing of a readline-decoupled repl loop, call
                     # interact_with_readline above
                     break
                 except KeyboardInterrupt:
                     # this should not be necessary, but KeyboardInterrupt
                     # handling seems rather unpredictable...
                     self.write("\nKeyboardInterrupt in interact()\n")
 
     def _replace_rlhist_multiline(self, source_raw, hlen_before_cell):
         """Store multiple lines as a single entry in history"""
 
         # do nothing without readline or disabled multiline
         if not self.has_readline or not self.multiline_history:
             return hlen_before_cell
 
         # windows rl has no remove_history_item
         if not hasattr(self.readline, "remove_history_item"):
             return hlen_before_cell
 
         # skip empty cells
         if not source_raw.rstrip():
             return hlen_before_cell
 
         # nothing changed do nothing, e.g. when rl removes consecutive dups
         hlen = self.readline.get_current_history_length()
         if hlen == hlen_before_cell:
             return hlen_before_cell
 
         for i in range(hlen - hlen_before_cell):
             self.readline.remove_history_item(hlen - i - 1)
         stdin_encoding = get_stream_enc(sys.stdin, 'utf-8')
         self.readline.add_history(py3compat.unicode_to_str(source_raw.rstrip(),
                                     stdin_encoding))
         return self.readline.get_current_history_length()
 
     def interact(self, display_banner=None):
         """Closely emulate the interactive Python console."""
 
         # batch run -> do not interact
         if self.exit_now:
             return
 
         if display_banner is None:
             display_banner = self.display_banner
 
         if isinstance(display_banner, basestring):
             self.show_banner(display_banner)
         elif display_banner:
             self.show_banner()
 
         more = False
 
         if self.has_readline:
             self.readline_startup_hook(self.pre_readline)
             hlen_b4_cell = self.readline.get_current_history_length()
         else:
             hlen_b4_cell = 0
         # exit_now is set by a call to %Exit or %Quit, through the
         # ask_exit callback.
 
         while not self.exit_now:
             self.hooks.pre_prompt_hook()
             if more:
                 try:
                     prompt = self.prompt_manager.render('in2')
                 except:
                     self.showtraceback()
                 if self.autoindent:
                     self.rl_do_indent = True
 
             else:
                 try:
                     prompt = self.separate_in + self.prompt_manager.render('in')
                 except:
                     self.showtraceback()
             try:
                 line = self.raw_input(prompt)
                 if self.exit_now:
                     # quick exit on sys.std[in|out] close
                     break
                 if self.autoindent:
                     self.rl_do_indent = False
 
             except KeyboardInterrupt:
                 #double-guard against keyboardinterrupts during kbdint handling
                 try:
                     self.write('\nKeyboardInterrupt\n')
                     source_raw = self.input_splitter.source_raw_reset()[1]
                     hlen_b4_cell = \
                         self._replace_rlhist_multiline(source_raw, hlen_b4_cell)
                     more = False
                 except KeyboardInterrupt:
                     pass
             except EOFError:
                 if self.autoindent:
                     self.rl_do_indent = False
                     if self.has_readline:
                         self.readline_startup_hook(None)
                 self.write('\n')
                 self.exit()
             except bdb.BdbQuit:
                 warn('The Python debugger has exited with a BdbQuit exception.\n'
                      'Because of how pdb handles the stack, it is impossible\n'
                      'for IPython to properly format this particular exception.\n'
                      'IPython will resume normal operation.')
             except:
                 # exceptions here are VERY RARE, but they can be triggered
                 # asynchronously by signal handlers, for example.
                 self.showtraceback()
             else:
                 self.input_splitter.push(line)
                 more = self.input_splitter.push_accepts_more()
                 if (self.SyntaxTB.last_syntax_error and
                     self.autoedit_syntax):
                     self.edit_syntax_error()
                 if not more:
                     source_raw = self.input_splitter.source_raw_reset()[1]
                     self.run_cell(source_raw, store_history=True)
                     hlen_b4_cell = \
                         self._replace_rlhist_multiline(source_raw, hlen_b4_cell)
 
         # Turn off the exit flag, so the mainloop can be restarted if desired
         self.exit_now = False
 
     def raw_input(self, prompt=''):
         """Write a prompt and read a line.
 
         The returned line does not include the trailing newline.
         When the user enters the EOF key sequence, EOFError is raised.
 
         Optional inputs:
 
           - prompt(''): a string to be printed to prompt the user.
 
           - continue_prompt(False): whether this line is the first one or a
           continuation in a sequence of inputs.
         """
         # Code run by the user may have modified the readline completer state.
         # We must ensure that our completer is back in place.
 
         if self.has_readline:
             self.set_readline_completer()
 
         try:
             line = py3compat.str_to_unicode(self.raw_input_original(prompt))
         except ValueError:
             warn("\n********\nYou or a %run:ed script called sys.stdin.close()"
                  " or sys.stdout.close()!\nExiting IPython!")
             self.ask_exit()
             return ""
 
         # Try to be reasonably smart about not re-indenting pasted input more
         # than necessary.  We do this by trimming out the auto-indent initial
         # spaces, if the user's actual input started itself with whitespace.
         if self.autoindent:
             if num_ini_spaces(line) > self.indent_current_nsp:
                 line = line[self.indent_current_nsp:]
                 self.indent_current_nsp = 0
 
         return line
 
     #-------------------------------------------------------------------------
     # Methods to support auto-editing of SyntaxErrors.
     #-------------------------------------------------------------------------
 
     def edit_syntax_error(self):
         """The bottom half of the syntax error handler called in the main loop.
 
         Loop until syntax error is fixed or user cancels.
         """
 
         while self.SyntaxTB.last_syntax_error:
             # copy and clear last_syntax_error
             err = self.SyntaxTB.clear_err_state()
             if not self._should_recompile(err):
                 return
             try:
                 # may set last_syntax_error again if a SyntaxError is raised
                 self.safe_execfile(err.filename,self.user_ns)
             except:
                 self.showtraceback()
             else:
                 try:
                     f = open(err.filename)
                     try:
                         # This should be inside a display_trap block and I
                         # think it is.
                         sys.displayhook(f.read())
                     finally:
                         f.close()
                 except:
                     self.showtraceback()
 
     def _should_recompile(self,e):
         """Utility routine for edit_syntax_error"""
 
         if e.filename in ('<ipython console>','<input>','<string>',
                           '<console>','<BackgroundJob compilation>',
                           None):
 
             return False
         try:
             if (self.autoedit_syntax and
                 not self.ask_yes_no('Return to editor to correct syntax error? '
                               '[Y/n] ','y')):
                 return False
         except EOFError:
             return False
 
         def int0(x):
             try:
                 return int(x)
             except TypeError:
                 return 0
         # always pass integer line and offset values to editor hook
         try:
             self.hooks.fix_error_editor(e.filename,
                 int0(e.lineno),int0(e.offset),e.msg)
         except TryNext:
             warn('Could not open editor')
             return False
         return True
 
     #-------------------------------------------------------------------------
     # Things related to exiting
     #-------------------------------------------------------------------------
 
     def ask_exit(self):
         """ Ask the shell to exit. Can be overiden and used as a callback. """
         self.exit_now = True
 
     def exit(self):
         """Handle interactive exit.
 
         This method calls the ask_exit callback."""
         if self.confirm_exit:
             if self.ask_yes_no('Do you really want to exit ([y]/n)?','y'):
                 self.ask_exit()
         else:
             self.ask_exit()
 
     #-------------------------------------------------------------------------
     # Things related to magics
     #-------------------------------------------------------------------------
 
     def init_magics(self):
         super(TerminalInteractiveShell, self).init_magics()
-        self.define_magic('autoindent', magic_autoindent)
-        self.define_magic('cpaste', magic_cpaste)
-        self.define_magic('paste', magic_paste)
-        try:
-            magic_cls
-        except NameError:
-            pass
-        else:
-            self.define_magic('cls', magic_cls)
+        self.register_magics(TerminalMagics)
 
     def showindentationerror(self):
         super(TerminalInteractiveShell, self).showindentationerror()
         print("If you want to paste code into IPython, try the "
               "%paste and %cpaste magic functions.")
 
 
 InteractiveShellABC.register(TerminalInteractiveShell)