djavu-asus/emacs/elpy/rpc-venv/lib/python3.11/site-packages/parso/python/prefix.py

   1 import re
   2 from codecs import BOM_UTF8
   3 from typing import Tuple
   4
   5 from parso.python.tokenize import group
   6
   7 unicode_bom = BOM_UTF8.decode('utf-8')
   8
   9
  10 class PrefixPart:
  11     def __init__(self, leaf, typ, value, spacing='', start_pos=None):
  12         assert start_pos is not None
  13         self.parent = leaf
  14         self.type = typ
  15         self.value = value
  16         self.spacing = spacing
  17         self.start_pos: Tuple[int, int] = start_pos
  18
  19     @property
  20     def end_pos(self) -> Tuple[int, int]:
  21         if self.value.endswith('\n') or self.value.endswith('\r'):
  22             return self.start_pos[0] + 1, 0
  23         if self.value == unicode_bom:
  24             # The bom doesn't have a length at the start of a Python file.
  25             return self.start_pos
  26         return self.start_pos[0], self.start_pos[1] + len(self.value)
  27
  28     def create_spacing_part(self):
  29         column = self.start_pos[1] - len(self.spacing)
  30         return PrefixPart(
  31             self.parent, 'spacing', self.spacing,
  32             start_pos=(self.start_pos[0], column)
  33         )
  34
  35     def __repr__(self):
  36         return '%s(%s, %s, %s)' % (
  37             self.__class__.__name__,
  38             self.type,
  39             repr(self.value),
  40             self.start_pos
  41         )
  42
  43     def search_ancestor(self, *node_types):
  44         node = self.parent
  45         while node is not None:
  46             if node.type in node_types:
  47                 return node
  48             node = node.parent
  49         return None
  50
  51
  52 _comment = r'#[^\n\r\f]*'
  53 _backslash = r'\\\r?\n|\\\r'
  54 _newline = r'\r?\n|\r'
  55 _form_feed = r'\f'
  56 _only_spacing = '$'
  57 _spacing = r'[ \t]*'
  58 _bom = unicode_bom
  59
  60 _regex = group(
  61     _comment, _backslash, _newline, _form_feed, _only_spacing, _bom,
  62     capture=True
  63 )
  64 _regex = re.compile(group(_spacing, capture=True) + _regex)
  65
  66
  67 _types = {
  68     '#': 'comment',
  69     '\\': 'backslash',
  70     '\f': 'formfeed',
  71     '\n': 'newline',
  72     '\r': 'newline',
  73     unicode_bom: 'bom'
  74 }
  75
  76
  77 def split_prefix(leaf, start_pos):
  78     line, column = start_pos
  79     start = 0
  80     value = spacing = ''
  81     bom = False
  82     while start != len(leaf.prefix):
  83         match = _regex.match(leaf.prefix, start)
  84         spacing = match.group(1)
  85         value = match.group(2)
  86         if not value:
  87             break
  88         type_ = _types[value[0]]
  89         yield PrefixPart(
  90             leaf, type_, value, spacing,
  91             start_pos=(line, column + start - int(bom) + len(spacing))
  92         )
  93         if type_ == 'bom':
  94             bom = True
  95
  96         start = match.end(0)
  97         if value.endswith('\n') or value.endswith('\r'):
  98             line += 1
  99             column = -start
 100
 101     if value:
 102         spacing = ''
 103     yield PrefixPart(
 104         leaf, 'spacing', spacing,
 105         start_pos=(line, column + start)
 106     )