djavu-asus/elpy/rpc-venv/lib/python3.11/site-packages/black/brackets.py

   1 """Builds on top of nodes.py to track brackets."""
   2
   3 from dataclasses import dataclass, field
   4 from typing import Dict, Final, Iterable, List, Optional, Sequence, Set, Tuple, Union
   5
   6 from black.nodes import (
   7     BRACKET,
   8     CLOSING_BRACKETS,
   9     COMPARATORS,
  10     LOGIC_OPERATORS,
  11     MATH_OPERATORS,
  12     OPENING_BRACKETS,
  13     UNPACKING_PARENTS,
  14     VARARGS_PARENTS,
  15     is_vararg,
  16     syms,
  17 )
  18 from blib2to3.pgen2 import token
  19 from blib2to3.pytree import Leaf, Node
  20
  21 # types
  22 LN = Union[Leaf, Node]
  23 Depth = int
  24 LeafID = int
  25 NodeType = int
  26 Priority = int
  27
  28
  29 COMPREHENSION_PRIORITY: Final = 20
  30 COMMA_PRIORITY: Final = 18
  31 TERNARY_PRIORITY: Final = 16
  32 LOGIC_PRIORITY: Final = 14
  33 STRING_PRIORITY: Final = 12
  34 COMPARATOR_PRIORITY: Final = 10
  35 MATH_PRIORITIES: Final = {
  36     token.VBAR: 9,
  37     token.CIRCUMFLEX: 8,
  38     token.AMPER: 7,
  39     token.LEFTSHIFT: 6,
  40     token.RIGHTSHIFT: 6,
  41     token.PLUS: 5,
  42     token.MINUS: 5,
  43     token.STAR: 4,
  44     token.SLASH: 4,
  45     token.DOUBLESLASH: 4,
  46     token.PERCENT: 4,
  47     token.AT: 4,
  48     token.TILDE: 3,
  49     token.DOUBLESTAR: 2,
  50 }
  51 DOT_PRIORITY: Final = 1
  52
  53
  54 class BracketMatchError(Exception):
  55     """Raised when an opening bracket is unable to be matched to a closing bracket."""
  56
  57
  58 @dataclass
  59 class BracketTracker:
  60     """Keeps track of brackets on a line."""
  61
  62     depth: int = 0
  63     bracket_match: Dict[Tuple[Depth, NodeType], Leaf] = field(default_factory=dict)
  64     delimiters: Dict[LeafID, Priority] = field(default_factory=dict)
  65     previous: Optional[Leaf] = None
  66     _for_loop_depths: List[int] = field(default_factory=list)
  67     _lambda_argument_depths: List[int] = field(default_factory=list)
  68     invisible: List[Leaf] = field(default_factory=list)
  69
  70     def mark(self, leaf: Leaf) -> None:
  71         """Mark `leaf` with bracket-related metadata. Keep track of delimiters.
  72
  73         All leaves receive an int `bracket_depth` field that stores how deep
  74         within brackets a given leaf is. 0 means there are no enclosing brackets
  75         that started on this line.
  76
  77         If a leaf is itself a closing bracket and there is a matching opening
  78         bracket earlier, it receives an `opening_bracket` field with which it forms a
  79         pair. This is a one-directional link to avoid reference cycles. Closing
  80         bracket without opening happens on lines continued from previous
  81         breaks, e.g. `) -> "ReturnType":` as part of a funcdef where we place
  82         the return type annotation on its own line of the previous closing RPAR.
  83
  84         If a leaf is a delimiter (a token on which Black can split the line if
  85         needed) and it's on depth 0, its `id()` is stored in the tracker's
  86         `delimiters` field.
  87         """
  88         if leaf.type == token.COMMENT:
  89             return
  90
  91         if (
  92             self.depth == 0
  93             and leaf.type in CLOSING_BRACKETS
  94             and (self.depth, leaf.type) not in self.bracket_match
  95         ):
  96             return
  97
  98         self.maybe_decrement_after_for_loop_variable(leaf)
  99         self.maybe_decrement_after_lambda_arguments(leaf)
 100         if leaf.type in CLOSING_BRACKETS:
 101             self.depth -= 1
 102             try:
 103                 opening_bracket = self.bracket_match.pop((self.depth, leaf.type))
 104             except KeyError as e:
 105                 raise BracketMatchError(
 106                     "Unable to match a closing bracket to the following opening"
 107                     f" bracket: {leaf}"
 108                 ) from e
 109             leaf.opening_bracket = opening_bracket
 110             if not leaf.value:
 111                 self.invisible.append(leaf)
 112         leaf.bracket_depth = self.depth
 113         if self.depth == 0:
 114             delim = is_split_before_delimiter(leaf, self.previous)
 115             if delim and self.previous is not None:
 116                 self.delimiters[id(self.previous)] = delim
 117             else:
 118                 delim = is_split_after_delimiter(leaf, self.previous)
 119                 if delim:
 120                     self.delimiters[id(leaf)] = delim
 121         if leaf.type in OPENING_BRACKETS:
 122             self.bracket_match[self.depth, BRACKET[leaf.type]] = leaf
 123             self.depth += 1
 124             if not leaf.value:
 125                 self.invisible.append(leaf)
 126         self.previous = leaf
 127         self.maybe_increment_lambda_arguments(leaf)
 128         self.maybe_increment_for_loop_variable(leaf)
 129
 130     def any_open_brackets(self) -> bool:
 131         """Return True if there is an yet unmatched open bracket on the line."""
 132         return bool(self.bracket_match)
 133
 134     def max_delimiter_priority(self, exclude: Iterable[LeafID] = ()) -> Priority:
 135         """Return the highest priority of a delimiter found on the line.
 136
 137         Values are consistent with what `is_split_*_delimiter()` return.
 138         Raises ValueError on no delimiters.
 139         """
 140         return max(v for k, v in self.delimiters.items() if k not in exclude)
 141
 142     def delimiter_count_with_priority(self, priority: Priority = 0) -> int:
 143         """Return the number of delimiters with the given `priority`.
 144
 145         If no `priority` is passed, defaults to max priority on the line.
 146         """
 147         if not self.delimiters:
 148             return 0
 149
 150         priority = priority or self.max_delimiter_priority()
 151         return sum(1 for p in self.delimiters.values() if p == priority)
 152
 153     def maybe_increment_for_loop_variable(self, leaf: Leaf) -> bool:
 154         """In a for loop, or comprehension, the variables are often unpacks.
 155
 156         To avoid splitting on the comma in this situation, increase the depth of
 157         tokens between `for` and `in`.
 158         """
 159         if leaf.type == token.NAME and leaf.value == "for":
 160             self.depth += 1
 161             self._for_loop_depths.append(self.depth)
 162             return True
 163
 164         return False
 165
 166     def maybe_decrement_after_for_loop_variable(self, leaf: Leaf) -> bool:
 167         """See `maybe_increment_for_loop_variable` above for explanation."""
 168         if (
 169             self._for_loop_depths
 170             and self._for_loop_depths[-1] == self.depth
 171             and leaf.type == token.NAME
 172             and leaf.value == "in"
 173         ):
 174             self.depth -= 1
 175             self._for_loop_depths.pop()
 176             return True
 177
 178         return False
 179
 180     def maybe_increment_lambda_arguments(self, leaf: Leaf) -> bool:
 181         """In a lambda expression, there might be more than one argument.
 182
 183         To avoid splitting on the comma in this situation, increase the depth of
 184         tokens between `lambda` and `:`.
 185         """
 186         if leaf.type == token.NAME and leaf.value == "lambda":
 187             self.depth += 1
 188             self._lambda_argument_depths.append(self.depth)
 189             return True
 190
 191         return False
 192
 193     def maybe_decrement_after_lambda_arguments(self, leaf: Leaf) -> bool:
 194         """See `maybe_increment_lambda_arguments` above for explanation."""
 195         if (
 196             self._lambda_argument_depths
 197             and self._lambda_argument_depths[-1] == self.depth
 198             and leaf.type == token.COLON
 199         ):
 200             self.depth -= 1
 201             self._lambda_argument_depths.pop()
 202             return True
 203
 204         return False
 205
 206     def get_open_lsqb(self) -> Optional[Leaf]:
 207         """Return the most recent opening square bracket (if any)."""
 208         return self.bracket_match.get((self.depth - 1, token.RSQB))
 209
 210
 211 def is_split_after_delimiter(leaf: Leaf, previous: Optional[Leaf] = None) -> Priority:
 212     """Return the priority of the `leaf` delimiter, given a line break after it.
 213
 214     The delimiter priorities returned here are from those delimiters that would
 215     cause a line break after themselves.
 216
 217     Higher numbers are higher priority.
 218     """
 219     if leaf.type == token.COMMA:
 220         return COMMA_PRIORITY
 221
 222     return 0
 223
 224
 225 def is_split_before_delimiter(leaf: Leaf, previous: Optional[Leaf] = None) -> Priority:
 226     """Return the priority of the `leaf` delimiter, given a line break before it.
 227
 228     The delimiter priorities returned here are from those delimiters that would
 229     cause a line break before themselves.
 230
 231     Higher numbers are higher priority.
 232     """
 233     if is_vararg(leaf, within=VARARGS_PARENTS | UNPACKING_PARENTS):
 234         # * and ** might also be MATH_OPERATORS but in this case they are not.
 235         # Don't treat them as a delimiter.
 236         return 0
 237
 238     if (
 239         leaf.type == token.DOT
 240         and leaf.parent
 241         and leaf.parent.type not in {syms.import_from, syms.dotted_name}
 242         and (previous is None or previous.type in CLOSING_BRACKETS)
 243     ):
 244         return DOT_PRIORITY
 245
 246     if (
 247         leaf.type in MATH_OPERATORS
 248         and leaf.parent
 249         and leaf.parent.type not in {syms.factor, syms.star_expr}
 250     ):
 251         return MATH_PRIORITIES[leaf.type]
 252
 253     if leaf.type in COMPARATORS:
 254         return COMPARATOR_PRIORITY
 255
 256     if (
 257         leaf.type == token.STRING
 258         and previous is not None
 259         and previous.type == token.STRING
 260     ):
 261         return STRING_PRIORITY
 262
 263     if leaf.type not in {token.NAME, token.ASYNC}:
 264         return 0
 265
 266     if (
 267         leaf.value == "for"
 268         and leaf.parent
 269         and leaf.parent.type in {syms.comp_for, syms.old_comp_for}
 270         or leaf.type == token.ASYNC
 271     ):
 272         if (
 273             not isinstance(leaf.prev_sibling, Leaf)
 274             or leaf.prev_sibling.value != "async"
 275         ):
 276             return COMPREHENSION_PRIORITY
 277
 278     if (
 279         leaf.value == "if"
 280         and leaf.parent
 281         and leaf.parent.type in {syms.comp_if, syms.old_comp_if}
 282     ):
 283         return COMPREHENSION_PRIORITY
 284
 285     if leaf.value in {"if", "else"} and leaf.parent and leaf.parent.type == syms.test:
 286         return TERNARY_PRIORITY
 287
 288     if leaf.value == "is":
 289         return COMPARATOR_PRIORITY
 290
 291     if (
 292         leaf.value == "in"
 293         and leaf.parent
 294         and leaf.parent.type in {syms.comp_op, syms.comparison}
 295         and not (
 296             previous is not None
 297             and previous.type == token.NAME
 298             and previous.value == "not"
 299         )
 300     ):
 301         return COMPARATOR_PRIORITY
 302
 303     if (
 304         leaf.value == "not"
 305         and leaf.parent
 306         and leaf.parent.type == syms.comp_op
 307         and not (
 308             previous is not None
 309             and previous.type == token.NAME
 310             and previous.value == "is"
 311         )
 312     ):
 313         return COMPARATOR_PRIORITY
 314
 315     if leaf.value in LOGIC_OPERATORS and leaf.parent:
 316         return LOGIC_PRIORITY
 317
 318     return 0
 319
 320
 321 def max_delimiter_priority_in_atom(node: LN) -> Priority:
 322     """Return maximum delimiter priority inside `node`.
 323
 324     This is specific to atoms with contents contained in a pair of parentheses.
 325     If `node` isn't an atom or there are no enclosing parentheses, returns 0.
 326     """
 327     if node.type != syms.atom:
 328         return 0
 329
 330     first = node.children[0]
 331     last = node.children[-1]
 332     if not (first.type == token.LPAR and last.type == token.RPAR):
 333         return 0
 334
 335     bt = BracketTracker()
 336     for c in node.children[1:-1]:
 337         if isinstance(c, Leaf):
 338             bt.mark(c)
 339         else:
 340             for leaf in c.leaves():
 341                 bt.mark(leaf)
 342     try:
 343         return bt.max_delimiter_priority()
 344
 345     except ValueError:
 346         return 0
 347
 348
 349 def get_leaves_inside_matching_brackets(leaves: Sequence[Leaf]) -> Set[LeafID]:
 350     """Return leaves that are inside matching brackets.
 351
 352     The input `leaves` can have non-matching brackets at the head or tail parts.
 353     Matching brackets are included.
 354     """
 355     try:
 356         # Start with the first opening bracket and ignore closing brackets before.
 357         start_index = next(
 358             i for i, l in enumerate(leaves) if l.type in OPENING_BRACKETS
 359         )
 360     except StopIteration:
 361         return set()
 362     bracket_stack = []
 363     ids = set()
 364     for i in range(start_index, len(leaves)):
 365         leaf = leaves[i]
 366         if leaf.type in OPENING_BRACKETS:
 367             bracket_stack.append((BRACKET[leaf.type], i))
 368         if leaf.type in CLOSING_BRACKETS:
 369             if bracket_stack and leaf.type == bracket_stack[-1][0]:
 370                 _, start = bracket_stack.pop()
 371                 for j in range(start, i + 1):
 372                     ids.add(id(leaves[j]))
 373             else:
 374                 break
 375     return ids