utils: coloransi: Escape Unicode U0001 and U0002 non-printable characters.

Fixes  #13637.

These Unicode characters, would cause problems when processed by LaTeX
to generate the info or PDF documentation targets.

* IPython/utils/coloransi.py (InputTermColors): Escape the backslashes
in \001 and \002 so that they are shown as literals '\001' and '\002'
strings in the Sphinx-generated documentation rather than as
non-printable Unicode characters.

IPython/utils/coloransi.py

@@ -1,187 +1,187 b''
 # -*- coding: utf-8 -*-
 """Tools for coloring text in ANSI terminals.
 """
 
 #*****************************************************************************
 #       Copyright (C) 2002-2006 Fernando Perez. <[e-mail]>
 #
 #  Distributed under the terms of the BSD License.  The full license is in
 #  the file COPYING, distributed as part of this software.
 #*****************************************************************************
 
 __all__ = ['TermColors','InputTermColors','ColorScheme','ColorSchemeTable']
 
 import os
 
 from IPython.utils.ipstruct import Struct
 
 color_templates = (
         # Dark colors
         ("Black"       , "0;30"),
         ("Red"         , "0;31"),
         ("Green"       , "0;32"),
         ("Brown"       , "0;33"),
         ("Blue"        , "0;34"),
         ("Purple"      , "0;35"),
         ("Cyan"        , "0;36"),
         ("LightGray"   , "0;37"),
         # Light colors
         ("DarkGray"    , "1;30"),
         ("LightRed"    , "1;31"),
         ("LightGreen"  , "1;32"),
         ("Yellow"      , "1;33"),
         ("LightBlue"   , "1;34"),
         ("LightPurple" , "1;35"),
         ("LightCyan"   , "1;36"),
         ("White"       , "1;37"),
         # Blinking colors.  Probably should not be used in anything serious.
         ("BlinkBlack"  , "5;30"),
         ("BlinkRed"    , "5;31"),
         ("BlinkGreen"  , "5;32"),
         ("BlinkYellow" , "5;33"),
         ("BlinkBlue"   , "5;34"),
         ("BlinkPurple" , "5;35"),
         ("BlinkCyan"   , "5;36"),
         ("BlinkLightGray", "5;37"),
         )
 
 def make_color_table(in_class):
     """Build a set of color attributes in a class.
 
     Helper function for building the :class:`TermColors` and
     :class`InputTermColors`.
     """
     for name,value in color_templates:
         setattr(in_class,name,in_class._base % value)
 
 class TermColors:
     """Color escape sequences.
 
     This class defines the escape sequences for all the standard (ANSI?)
     colors in terminals. Also defines a NoColor escape which is just the null
     string, suitable for defining 'dummy' color schemes in terminals which get
     confused by color escapes.
 
     This class should be used as a mixin for building color schemes."""
 
     NoColor = ''  # for color schemes in color-less terminals.
     Normal = '\033[0m'   # Reset normal coloring
     _base  = '\033[%sm'  # Template for all other colors
 
 # Build the actual color table as a set of class attributes:
 make_color_table(TermColors)
 
 class InputTermColors:
     """Color escape sequences for input prompts.
 
-    This class is similar to TermColors, but the escapes are wrapped in \001
-    and \002 so that readline can properly know the length of each line and
+    This class is similar to TermColors, but the escapes are wrapped in \\001
+    and \\002 so that readline can properly know the length of each line and
     can wrap lines accordingly.  Use this class for any colored text which
     needs to be used in input prompts, such as in calls to raw_input().
 
     This class defines the escape sequences for all the standard (ANSI?)
     colors in terminals. Also defines a NoColor escape which is just the null
     string, suitable for defining 'dummy' color schemes in terminals which get
     confused by color escapes.
 
     This class should be used as a mixin for building color schemes."""
 
     NoColor = ''  # for color schemes in color-less terminals.
 
     if os.name == 'nt' and os.environ.get('TERM','dumb') == 'emacs':
         # (X)emacs on W32 gets confused with \001 and \002 so we remove them
         Normal = '\033[0m'   # Reset normal coloring
         _base  = '\033[%sm'  # Template for all other colors
     else:
         Normal = '\001\033[0m\002'   # Reset normal coloring
         _base  = '\001\033[%sm\002'  # Template for all other colors
 
 # Build the actual color table as a set of class attributes:
 make_color_table(InputTermColors)
 
 class NoColors:
     """This defines all the same names as the colour classes, but maps them to
     empty strings, so it can easily be substituted to turn off colours."""
     NoColor = ''
     Normal  = ''
 
 for name, value in color_templates:
     setattr(NoColors, name, '')
 
 class ColorScheme:
     """Generic color scheme class. Just a name and a Struct."""
     def __init__(self,__scheme_name_,colordict=None,**colormap):
         self.name = __scheme_name_
         if colordict is None:
             self.colors = Struct(**colormap)
         else:
             self.colors = Struct(colordict)
 
     def copy(self,name=None):
         """Return a full copy of the object, optionally renaming it."""
         if name is None:
             name = self.name
         return ColorScheme(name, self.colors.dict())
 
 class ColorSchemeTable(dict):
     """General class to handle tables of color schemes.
 
     It's basically a dict of color schemes with a couple of shorthand
     attributes and some convenient methods.
 
     active_scheme_name -> obvious
     active_colors -> actual color table of the active scheme"""
 
     def __init__(self, scheme_list=None, default_scheme=''):
         """Create a table of color schemes.
 
         The table can be created empty and manually filled or it can be
         created with a list of valid color schemes AND the specification for
         the default active scheme.
         """
 
         # create object attributes to be set later
         self.active_scheme_name = ''
         self.active_colors = None
 
         if scheme_list:
             if default_scheme == '':
                 raise ValueError('you must specify the default color scheme')
             for scheme in scheme_list:
                 self.add_scheme(scheme)
             self.set_active_scheme(default_scheme)
 
     def copy(self):
         """Return full copy of object"""
         return ColorSchemeTable(self.values(),self.active_scheme_name)
 
     def add_scheme(self,new_scheme):
         """Add a new color scheme to the table."""
         if not isinstance(new_scheme,ColorScheme):
             raise ValueError('ColorSchemeTable only accepts ColorScheme instances')
         self[new_scheme.name] = new_scheme
 
     def set_active_scheme(self,scheme,case_sensitive=0):
         """Set the currently active scheme.
 
         Names are by default compared in a case-insensitive way, but this can
         be changed by setting the parameter case_sensitive to true."""
 
         scheme_names = list(self.keys())
         if case_sensitive:
             valid_schemes = scheme_names
             scheme_test = scheme
         else:
             valid_schemes = [s.lower() for s in scheme_names]
             scheme_test = scheme.lower()
         try:
             scheme_idx = valid_schemes.index(scheme_test)
         except ValueError as e:
             raise ValueError('Unrecognized color scheme: ' + scheme + \
                   '\nValid schemes: '+str(scheme_names).replace("'', ",'')) from e
         else:
             active = scheme_names[scheme_idx]
             self.active_scheme_name = active
             self.active_colors = self[active].colors
             # Now allow using '' as an index for the current active scheme
             self[''] = self[active]