#!/usr/bin/env python
# -*- coding: utf-8 -*-
"""\
bug_configparser.py - configparser.ConfigParser.clean and .update

======  ====================
usage:  bug_configparser.py
======  ====================
"""

import sys

try:
    from StringIO import StringIO
except ImportError:
    from io import StringIO

try:
    import configparser
except ImportError:
    import ConfigParser as configparser

def configparser_clear_compat(self):                       # ||:mth:||
    """Python 3 compatible clear method."""
    raise ValueError('Cannot remove the default section.')

def configparser_update_compat(self, other=None, **kwds):  # ||:mth:||
    """Python 3 compatible update method."""

    if other is None:
        other = ()

    if hasattr(other, "items"):
        for key, value in other.items():
            if key == 'DEFAULT':
                self.defaults().update(value)
            else:
                self._sections[key] = value
    elif hasattr(other, "keys"):
        for key in other.keys():
            if key == 'DEFAULT':
                self.defaults().update(other[key])
            else:
                self._sections[key] = other[key]
    else:
        for key, value in other:
            if key == 'DEFAULT':
                self.defaults().update(value)
            else:
                self._sections[key] = value
    for key, value in kwds.items():
            if key == 'DEFAULT':
                self.defaults().update(value)
            else:
                self._sections[key] = value

def configparser_clear(self):                              # ||:mth:||
    """Python 3 makes this a purely non-sensical thing:

    >>> cfg = configparser.ConfigParser()
    >>> if not hasattr(configparser.ConfigParser, 'clear'):
    ...     configparser.ConfigParser.clear = configparser_clear_compat
    >>> cfg.clear() #doctest: +ELLIPSIS
    Traceback (most recent call last):
    ...
    ValueError: Cannot remove the default section.

    This implementation deletes all sections except DEFAULT. Which is
    more like what is expected.

    >>> cfg = ConfigParser()
    >>> cfg.update({'DEFAULT': {'dkey': 'dval'}, 'section': {'skey': 'sval'}})

    >>> state = StringIO()
    >>> cfg.write(state)
    >>> ign = sys.stdout.write(state.getvalue())
    [DEFAULT]
    dkey = dval
    <BLANKLINE>
    [section]
    skey = sval
    <BLANKLINE>

    >>> cfg.clear()

    >>> state = StringIO()
    >>> cfg.write(state)
    >>> ign = sys.stdout.write(state.getvalue())
    [DEFAULT]
    dkey = dval
    <BLANKLINE>
    """

    for section in self.sections():
        del(self[section])

def configparser_update(self, other=None, **kwds):         # ||:mth:||
    """Python 3 implementation is counter-intuitive.

    It overwrites all sections except DEFAULT instead of updating
    them.

    >>> cfg = configparser.ConfigParser()
    >>> if not hasattr(configparser.ConfigParser, 'update'):
    ...     configparser.ConfigParser.update = configparser_update_compat
    >>> cfg.update({'DEFAULT': {'dkey': 'dval'}, 'section': {'skey': 'sval'}})
    >>> cfg.update({'DEFAULT': {'dkey1': 'dval1'}, 'section': {'skey1': 'sval1'}})
    >>> cfg.update((('section', {'skey2': 'sval2'}), ))
    >>> cfg.update(section={'skey2': 'sval2'})

    >>> state = StringIO()
    >>> cfg.write(state)
    >>> ign = sys.stdout.write(state.getvalue())
    [DEFAULT]
    dkey = dval
    dkey1 = dval1
    <BLANKLINE>
    [section]
    skey2 = sval2
    <BLANKLINE>

    Since :meth:`read_dict` almost behaves like :meth:`update`
    should, it can simply be called from :meth:`update`.

    >>> cfg = ConfigParser()
    >>> cfg.update({'DEFAULT': {'dkey': 'dval'}, 'section': {'skey': 'sval'}})
    >>> cfg.update({'DEFAULT': {'dkey1': 'dval1'}, 'section': {'skey1': 'sval1'}})
    >>> cfg.update((('section', {'skey2': 'sval2'}), ))
    >>> cfg.update(section={'skey2': 'sval2'})

    >>> state = StringIO()
    >>> cfg.write(state)
    >>> ign = sys.stdout.write(state.getvalue())
    [DEFAULT]
    dkey = dval
    dkey1 = dval1
    <BLANKLINE>
    [section]
    skey = sval
    skey1 = sval1
    skey2 = sval2
    <BLANKLINE>

    The reason can be found in _abcoll.py::

        def update(*args, **kwds):

            ...

            if isinstance(other, Mapping):
                for key in other:
                    self[key] = other[key]
            elif hasattr(other, "keys"):
                for key in other.keys():
                    self[key] = other[key]
            else:
                for key, value in other:
                    self[key] = value
            for key, value in kwds.items():
                self[key] = value
    """
    if other is None:
        other = ()
    for dict_ in configparser._default_dict(other), kwds:
        self.read_dict(dict_)

try:
    configparser.ConfigParser()['section']['key'] = 'value'
except KeyError:
    # Python 3.x
    class ConfigParser(configparser.ConfigParser):         # ||:cls:||
        # clear of MutableMapping is non-sensical in config context.
        clear = configparser_clear
        # update of MutableMapping is counter-intuitive.
        update = configparser_update
except AttributeError:
    # Python 2.x
    class ConfigParser(configparser.ConfigParser):         # ||:cls:||
        clear = configparser_clear
        update = configparser_update

        def __delitem__(self, key):                          # |:mth:|
            del(self._sections[key])

        def read_dict(self, dict_, source='<dict>'):         # |:mth:|
            """
            """
            for sname, section in dict_.items():
                sname = unicode(sname)
                if sname == 'DEFAULT':
                    defaults = self.defaults()
                    for key, value in section.items():
                        defaults[self.optionxform(key)] = value
                else:
                    if not self.has_section(sname):
                        self.add_section(sname)
                    for key, value in section.items():
                        # if issequence(value):
                        #     value = '\n'.join([str(v) for v in value])
                        # else:
                        #     value = str(value)
                        self.set(sname, key, unicode(str(value)))

import doctest
doctest.testmod()

# (progn (forward-line 1) (snip-insert "py.t.ide" t t "py") (insert "\n"))
#
# :ide-menu: Emacs IDE Main Menu - Buffer @BUFFER@
# . M-x `eIDE-menu' (eIDE-menu "z")

# :ide: COMPILE: Run with python3 w/o args
# . (progn (save-buffer) (compile (concat "python3 ./" (file-name-nondirectory (buffer-file-name)) " ")))

# :ide: COMPILE: Run w/o args
# . (progn (save-buffer) (compile (concat "python ./" (file-name-nondirectory (buffer-file-name)) " ")))

#
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