Generating lines of code.
"""
import sys
+from dataclasses import dataclass
from enum import Enum, auto
from functools import partial, wraps
from typing import Collection, Iterator, List, Optional, Set, Union, cast
from black.mode import Feature, Mode, Preview
from black.nodes import (
ASSIGNMENTS,
+ BRACKETS,
CLOSING_BRACKETS,
OPENING_BRACKETS,
RARROW,
yield result
+@dataclass
+class _RHSResult:
+ """Intermediate split result from a right hand split."""
+
+ head: Line
+ body: Line
+ tail: Line
+ opening_bracket: Leaf
+ closing_bracket: Leaf
+
+
def right_hand_split(
line: Line,
line_length: int,
Note: running this function modifies `bracket_depth` on the leaves of `line`.
"""
+ rhs_result = _first_right_hand_split(line, omit=omit)
+ yield from _maybe_split_omitting_optional_parens(
+ rhs_result, line, line_length, features=features, omit=omit
+ )
+
+
+def _first_right_hand_split(
+ line: Line,
+ omit: Collection[LeafID] = (),
+) -> _RHSResult:
+ """Split the line into head, body, tail starting with the last bracket pair.
+
+ Note: this function should not have side effects. It's relied upon by
+ _maybe_split_omitting_optional_parens to get an opinion whether to prefer
+ splitting on the right side of an assignment statement.
+ """
tail_leaves: List[Leaf] = []
body_leaves: List[Leaf] = []
head_leaves: List[Leaf] = []
tail_leaves, line, opening_bracket, component=_BracketSplitComponent.tail
)
bracket_split_succeeded_or_raise(head, body, tail)
+ return _RHSResult(head, body, tail, opening_bracket, closing_bracket)
+
+
+def _maybe_split_omitting_optional_parens(
+ rhs: _RHSResult,
+ line: Line,
+ line_length: int,
+ features: Collection[Feature] = (),
+ omit: Collection[LeafID] = (),
+) -> Iterator[Line]:
if (
Feature.FORCE_OPTIONAL_PARENTHESES not in features
# the opening bracket is an optional paren
- and opening_bracket.type == token.LPAR
- and not opening_bracket.value
+ and rhs.opening_bracket.type == token.LPAR
+ and not rhs.opening_bracket.value
# the closing bracket is an optional paren
- and closing_bracket.type == token.RPAR
- and not closing_bracket.value
+ and rhs.closing_bracket.type == token.RPAR
+ and not rhs.closing_bracket.value
# it's not an import (optional parens are the only thing we can split on
# in this case; attempting a split without them is a waste of time)
and not line.is_import
# there are no standalone comments in the body
- and not body.contains_standalone_comments(0)
+ and not rhs.body.contains_standalone_comments(0)
# and we can actually remove the parens
- and can_omit_invisible_parens(body, line_length)
+ and can_omit_invisible_parens(rhs.body, line_length)
):
- omit = {id(closing_bracket), *omit}
+ omit = {id(rhs.closing_bracket), *omit}
try:
- yield from right_hand_split(line, line_length, features=features, omit=omit)
- return
+ # The _RHSResult Omitting Optional Parens.
+ rhs_oop = _first_right_hand_split(line, omit=omit)
+ if not (
+ Preview.prefer_splitting_right_hand_side_of_assignments in line.mode
+ # the split is right after `=`
+ and len(rhs.head.leaves) >= 2
+ and rhs.head.leaves[-2].type == token.EQUAL
+ # the left side of assignement contains brackets
+ and any(leaf.type in BRACKETS for leaf in rhs.head.leaves[:-1])
+ # the left side of assignment is short enough (the -1 is for the ending
+ # optional paren)
+ and is_line_short_enough(rhs.head, line_length=line_length - 1)
+ # the left side of assignment won't explode further because of magic
+ # trailing comma
+ and rhs.head.magic_trailing_comma is None
+ # the split by omitting optional parens isn't preferred by some other
+ # reason
+ and not _prefer_split_rhs_oop(rhs_oop, line_length=line_length)
+ ):
+ yield from _maybe_split_omitting_optional_parens(
+ rhs_oop, line, line_length, features=features, omit=omit
+ )
+ return
except CannotSplit as e:
if not (
- can_be_split(body)
- or is_line_short_enough(body, line_length=line_length)
+ can_be_split(rhs.body)
+ or is_line_short_enough(rhs.body, line_length=line_length)
):
raise CannotSplit(
"Splitting failed, body is still too long and can't be split."
) from e
- elif head.contains_multiline_strings() or tail.contains_multiline_strings():
+ elif (
+ rhs.head.contains_multiline_strings()
+ or rhs.tail.contains_multiline_strings()
+ ):
raise CannotSplit(
"The current optional pair of parentheses is bound to fail to"
" satisfy the splitting algorithm because the head or the tail"
" line."
) from e
- ensure_visible(opening_bracket)
- ensure_visible(closing_bracket)
- for result in (head, body, tail):
+ ensure_visible(rhs.opening_bracket)
+ ensure_visible(rhs.closing_bracket)
+ for result in (rhs.head, rhs.body, rhs.tail):
if result:
yield result
+def _prefer_split_rhs_oop(rhs_oop: _RHSResult, line_length: int) -> bool:
+ """
+ Returns whether we should prefer the result from a split omitting optional parens.
+ """
+ has_closing_bracket_after_assign = False
+ for leaf in reversed(rhs_oop.head.leaves):
+ if leaf.type == token.EQUAL:
+ break
+ if leaf.type in CLOSING_BRACKETS:
+ has_closing_bracket_after_assign = True
+ break
+ return (
+ # contains matching brackets after the `=` (done by checking there is a
+ # closing bracket)
+ has_closing_bracket_after_assign
+ or (
+ # the split is actually from inside the optional parens (done by checking
+ # the first line still contains the `=`)
+ any(leaf.type == token.EQUAL for leaf in rhs_oop.head.leaves)
+ # the first line is short enough
+ and is_line_short_enough(rhs_oop.head, line_length=line_length)
+ )
+ # contains unsplittable type ignore
+ or rhs_oop.head.contains_unsplittable_type_ignore()
+ or rhs_oop.body.contains_unsplittable_type_ignore()
+ or rhs_oop.tail.contains_unsplittable_type_ignore()
+ )
+
+
def bracket_split_succeeded_or_raise(head: Line, body: Line, tail: Line) -> None:
"""Raise :exc:`CannotSplit` if the last left- or right-hand split failed.
syms.expr_stmt,
syms.assert_stmt,
syms.return_stmt,
+ syms.except_clause,
+ syms.funcdef,
# these ones aren't useful to end users, but they do please fuzzers
syms.for_stmt,
syms.del_stmt,
result.extend(transform_line(transformed_line, mode=mode, features=features))
+ features_set = set(features)
if (
- transform.__class__.__name__ != "rhs"
+ Feature.FORCE_OPTIONAL_PARENTHESES in features_set
+ or transform.__class__.__name__ != "rhs"
or not line.bracket_tracker.invisible
or any(bracket.value for bracket in line.bracket_tracker.invisible)
or line.contains_multiline_strings()
line_copy = line.clone()
append_leaves(line_copy, line, line.leaves)
- features_fop = set(features) | {Feature.FORCE_OPTIONAL_PARENTHESES}
+ features_fop = features_set | {Feature.FORCE_OPTIONAL_PARENTHESES}
second_opinion = run_transformer(
line_copy, transform, mode, features_fop, line_str=line_str
)
projects / etc / vim.git / blobdiff