X-Git-Url: https://git.madduck.net/etc/vim.git/blobdiff_plain/658c8d8d96047c5ba77be4aecc2545a22d5e35b9..72a3408965f944f39f1080a5b67c25790acdc4e2:/src/black/linegen.py diff --git a/src/black/linegen.py b/src/black/linegen.py index 244dbe7..2e75bc9 100644 --- a/src/black/linegen.py +++ b/src/black/linegen.py @@ -2,6 +2,7 @@ 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 @@ -24,6 +25,7 @@ from black.lines import ( from black.mode import Feature, Mode, Preview from black.nodes import ( ASSIGNMENTS, + BRACKETS, CLOSING_BRACKETS, OPENING_BRACKETS, RARROW, @@ -634,6 +636,17 @@ def left_hand_split(line: Line, _features: Collection[Feature] = ()) -> Iterator 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, @@ -648,6 +661,22 @@ def right_hand_split( 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] = [] @@ -683,37 +712,71 @@ def right_hand_split( 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" @@ -721,13 +784,42 @@ def right_hand_split( " 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. @@ -1176,6 +1268,8 @@ def maybe_make_parens_invisible_in_atom( 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, @@ -1325,8 +1419,10 @@ def run_transformer( 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() @@ -1343,7 +1439,7 @@ def run_transformer( 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 )