tokens.py

# # header
# coding: utf-8

from __future__ import unicode_literals

if False:  # MYPY
    from typing import Text, Any, Dict, Optional, List  # NOQA
    from .error import StreamMark  # NOQA

SHOWLINES = True


class Token(object):
    __slots__ = 'start_mark', 'end_mark', '_comment'

    def __init__(self, start_mark, end_mark):
        # type: (StreamMark, StreamMark) -> None
        self.start_mark = start_mark
        self.end_mark = end_mark

    def __repr__(self):
        # type: () -> Any
        # attributes = [key for key in self.__slots__ if not key.endswith('_mark') and
        #               hasattr('self', key)]
        attributes = [key for key in self.__slots__ if not key.endswith('_mark')]
        attributes.sort()
        arguments = ', '.join(['%s=%r' % (key, getattr(self, key)) for key in attributes])
        if SHOWLINES:
            try:
                arguments += ', line: ' + str(self.start_mark.line)
            except:  # NOQA
                pass
        try:
            arguments += ', comment: ' + str(self._comment)
        except:  # NOQA
            pass
        return '{}({})'.format(self.__class__.__name__, arguments)

    def add_post_comment(self, comment):
        # type: (Any) -> None
        if not hasattr(self, '_comment'):
            self._comment = [None, None]
        self._comment[0] = comment

    def add_pre_comments(self, comments):
        # type: (Any) -> None
        if not hasattr(self, '_comment'):
            self._comment = [None, None]
        assert self._comment[1] is None
        self._comment[1] = comments

    def get_comment(self):
        # type: () -> Any
        return getattr(self, '_comment', None)

    @property
    def comment(self):
        # type: () -> Any
        return getattr(self, '_comment', None)

    def move_comment(self, target, empty=False):
        # type: (Any, bool) -> Any
        """move a comment from this token to target (normally next token)
        used to combine e.g. comments before a BlockEntryToken to the
        ScalarToken that follows it
        empty is a special for empty values -> comment after key
        """
        c = self.comment
        if c is None:
            return
        # don't push beyond last element
        if isinstance(target, (StreamEndToken, DocumentStartToken)):
            return
        delattr(self, '_comment')
        tc = target.comment
        if not tc:  # target comment, just insert
            # special for empty value in key: value issue 25
            if empty:
                c = [c[0], c[1], None, None, c[0]]
            target._comment = c
            # nprint('mco2:', self, target, target.comment, empty)
            return self
        if c[0] and tc[0] or c[1] and tc[1]:
            raise NotImplementedError('overlap in comment %r %r' % (c, tc))
        if c[0]:
            tc[0] = c[0]
        if c[1]:
            tc[1] = c[1]
        return self

    def split_comment(self):
        # type: () -> Any
        """ split the post part of a comment, and return it
        as comment to be added. Delete second part if [None, None]
         abc:  # this goes to sequence
           # this goes to first element
           - first element
        """
        comment = self.comment
        if comment is None or comment[0] is None:
            return None  # nothing to do
        ret_val = [comment[0], None]
        if comment[1] is None:
            delattr(self, '_comment')
        return ret_val


# class BOMToken(Token):
#     id = '<byte order mark>'


class DirectiveToken(Token):
    __slots__ = 'name', 'value'
    id = '<directive>'

    def __init__(self, name, value, start_mark, end_mark):
        # type: (Any, Any, Any, Any) -> None
        Token.__init__(self, start_mark, end_mark)
        self.name = name
        self.value = value


class DocumentStartToken(Token):
    __slots__ = ()
    id = '<document start>'


class DocumentEndToken(Token):
    __slots__ = ()
    id = '<document end>'


class StreamStartToken(Token):
    __slots__ = ('encoding',)
    id = '<stream start>'

    def __init__(self, start_mark=None, end_mark=None, encoding=None):
        # type: (Any, Any, Any) -> None
        Token.__init__(self, start_mark, end_mark)
        self.encoding = encoding


class StreamEndToken(Token):
    __slots__ = ()
    id = '<stream end>'


class BlockSequenceStartToken(Token):
    __slots__ = ()
    id = '<block sequence start>'


class BlockMappingStartToken(Token):
    __slots__ = ()
    id = '<block mapping start>'


class BlockEndToken(Token):
    __slots__ = ()
    id = '<block end>'


class FlowSequenceStartToken(Token):
    __slots__ = ()
    id = '['


class FlowMappingStartToken(Token):
    __slots__ = ()
    id = '{'


class FlowSequenceEndToken(Token):
    __slots__ = ()
    id = ']'


class FlowMappingEndToken(Token):
    __slots__ = ()
    id = '}'


class KeyToken(Token):
    __slots__ = ()
    id = '?'

    # def x__repr__(self):
    #     return 'KeyToken({})'.format(
    #         self.start_mark.buffer[self.start_mark.index:].split(None, 1)[0])


class ValueToken(Token):
    __slots__ = ()
    id = ':'


class BlockEntryToken(Token):
    __slots__ = ()
    id = '-'


class FlowEntryToken(Token):
    __slots__ = ()
    id = ','


class AliasToken(Token):
    __slots__ = ('value',)
    id = '<alias>'

    def __init__(self, value, start_mark, end_mark):
        # type: (Any, Any, Any) -> None
        Token.__init__(self, start_mark, end_mark)
        self.value = value


class AnchorToken(Token):
    __slots__ = ('value',)
    id = '<anchor>'

    def __init__(self, value, start_mark, end_mark):
        # type: (Any, Any, Any) -> None
        Token.__init__(self, start_mark, end_mark)
        self.value = value


class TagToken(Token):
    __slots__ = ('value',)
    id = '<tag>'

    def __init__(self, value, start_mark, end_mark):
        # type: (Any, Any, Any) -> None
        Token.__init__(self, start_mark, end_mark)
        self.value = value


class ScalarToken(Token):
    __slots__ = 'value', 'plain', 'style'
    id = '<scalar>'

    def __init__(self, value, plain, start_mark, end_mark, style=None):
        # type: (Any, Any, Any, Any, Any) -> None
        Token.__init__(self, start_mark, end_mark)
        self.value = value
        self.plain = plain
        self.style = style


class CommentToken(Token):
    __slots__ = 'value', 'pre_done'
    id = '<comment>'

    def __init__(self, value, start_mark, end_mark):
        # type: (Any, Any, Any) -> None
        Token.__init__(self, start_mark, end_mark)
        self.value = value

    def reset(self):
        # type: () -> None
        if hasattr(self, 'pre_done'):
            delattr(self, 'pre_done')

    def __repr__(self):
        # type: () -> Any
        v = '{!r}'.format(self.value)
        if SHOWLINES:
            try:
                v += ', line: ' + str(self.start_mark.line)
                v += ', col: ' + str(self.start_mark.column)
            except:  # NOQA
                pass
        return 'CommentToken({})'.format(v)