"""
Generating lines of code.
"""
-from functools import partial, wraps
import sys
-from typing import Collection, Iterator, List, Optional, Set, Union
+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.nodes import WHITESPACE, RARROW, STATEMENT, STANDALONE_COMMENT
-from black.nodes import ASSIGNMENTS, OPENING_BRACKETS, CLOSING_BRACKETS
-from black.nodes import Visitor, syms, is_arith_like, ensure_visible
+from black.brackets import (
+ COMMA_PRIORITY,
+ DOT_PRIORITY,
+ get_leaves_inside_matching_brackets,
+ max_delimiter_priority_in_atom,
+)
+from black.comments import FMT_OFF, generate_comments, list_comments
+from black.lines import (
+ Line,
+ append_leaves,
+ can_be_split,
+ can_omit_invisible_parens,
+ is_line_short_enough,
+ line_to_string,
+)
+from black.mode import Feature, Mode, Preview
from black.nodes import (
+ ASSIGNMENTS,
+ BRACKETS,
+ CLOSING_BRACKETS,
+ OPENING_BRACKETS,
+ RARROW,
+ STANDALONE_COMMENT,
+ STATEMENT,
+ WHITESPACE,
+ Visitor,
+ ensure_visible,
+ is_arith_like,
+ is_atom_with_invisible_parens,
is_docstring,
is_empty_tuple,
- is_one_tuple,
+ is_lpar_token,
+ is_multiline_string,
+ is_name_token,
is_one_sequence_between,
+ is_one_tuple,
+ is_rpar_token,
+ is_stub_body,
+ is_stub_suite,
+ is_vararg,
+ is_walrus_assignment,
+ is_yield,
+ syms,
+ wrap_in_parentheses,
)
-from black.nodes import is_name_token, is_lpar_token, is_rpar_token
-from black.nodes import is_walrus_assignment, is_yield, is_vararg, is_multiline_string
-from black.nodes import is_stub_suite, is_stub_body, is_atom_with_invisible_parens
-from black.nodes import wrap_in_parentheses
-from black.brackets import max_delimiter_priority_in_atom
-from black.brackets import DOT_PRIORITY, COMMA_PRIORITY
-from black.lines import Line, line_to_string, is_line_short_enough
-from black.lines import can_omit_invisible_parens, can_be_split, append_leaves
-from black.comments import generate_comments, list_comments, FMT_OFF
from black.numerics import normalize_numeric_literal
-from black.strings import get_string_prefix, fix_docstring
-from black.strings import normalize_string_prefix, normalize_string_quotes
-from black.trans import Transformer, CannotTransform, StringMerger, StringSplitter
-from black.trans import StringParenWrapper, StringParenStripper, hug_power_op
-from black.mode import Mode, Feature, Preview
-
-from blib2to3.pytree import Node, Leaf
+from black.strings import (
+ fix_docstring,
+ get_string_prefix,
+ normalize_string_prefix,
+ normalize_string_quotes,
+)
+from black.trans import (
+ CannotTransform,
+ StringMerger,
+ StringParenStripper,
+ StringParenWrapper,
+ StringSplitter,
+ Transformer,
+ hug_power_op,
+)
from blib2to3.pgen2 import token
-
+from blib2to3.pytree import Leaf, Node
# types
LeafID = int
self.current_line.append(node)
yield from super().visit_default(node)
+ def visit_test(self, node: Node) -> Iterator[Line]:
+ """Visit an `x if y else z` test"""
+
+ if Preview.parenthesize_conditional_expressions in self.mode:
+ already_parenthesized = (
+ node.prev_sibling and node.prev_sibling.type == token.LPAR
+ )
+
+ if not already_parenthesized:
+ lpar = Leaf(token.LPAR, "")
+ rpar = Leaf(token.RPAR, "")
+ node.insert_child(0, lpar)
+ node.append_child(rpar)
+
+ yield from self.visit_default(node)
+
def visit_INDENT(self, node: Leaf) -> Iterator[Line]:
"""Increase indentation level, maybe yield a line."""
# In blib2to3 INDENT never holds comments.
yield from self.visit(child)
+ def visit_dictsetmaker(self, node: Node) -> Iterator[Line]:
+ if Preview.wrap_long_dict_values_in_parens in self.mode:
+ for i, child in enumerate(node.children):
+ if i == 0:
+ continue
+ if node.children[i - 1].type == token.COLON:
+ if child.type == syms.atom and child.children[0].type == token.LPAR:
+ if maybe_make_parens_invisible_in_atom(
+ child,
+ parent=node,
+ remove_brackets_around_comma=False,
+ ):
+ wrap_in_parentheses(node, child, visible=False)
+ else:
+ wrap_in_parentheses(node, child, visible=False)
+ yield from self.visit_default(node)
+
+ def visit_funcdef(self, node: Node) -> Iterator[Line]:
+ """Visit function definition."""
+ if Preview.annotation_parens not in self.mode:
+ yield from self.visit_stmt(node, keywords={"def"}, parens=set())
+ else:
+ yield from self.line()
+
+ # Remove redundant brackets around return type annotation.
+ is_return_annotation = False
+ for child in node.children:
+ if child.type == token.RARROW:
+ is_return_annotation = True
+ elif is_return_annotation:
+ if child.type == syms.atom and child.children[0].type == token.LPAR:
+ if maybe_make_parens_invisible_in_atom(
+ child,
+ parent=node,
+ remove_brackets_around_comma=False,
+ ):
+ wrap_in_parentheses(node, child, visible=False)
+ else:
+ wrap_in_parentheses(node, child, visible=False)
+ is_return_annotation = False
+
+ for child in node.children:
+ yield from self.visit(child)
+
def visit_match_case(self, node: Node) -> Iterator[Line]:
"""Visit either a match or case statement."""
normalize_invisible_parens(node, parens_after=set(), preview=self.mode.preview)
for child in children:
yield from self.visit(child)
- if child.type == token.ASYNC:
+ if child.type == token.ASYNC or child.type == STANDALONE_COMMENT:
+ # STANDALONE_COMMENT happens when `# fmt: skip` is applied on the async
+ # line.
break
internal_stmt = next(children)
):
wrap_in_parentheses(node, leaf)
+ if Preview.remove_redundant_parens in self.mode:
+ remove_await_parens(node)
+
yield from self.visit_default(node)
def visit_SEMI(self, leaf: Leaf) -> Iterator[Line]:
if is_docstring(leaf) and "\\\n" not in leaf.value:
# We're ignoring docstrings with backslash newline escapes because changing
# indentation of those changes the AST representation of the code.
- docstring = normalize_string_prefix(leaf.value)
+ if Preview.normalize_docstring_quotes_and_prefixes_properly in self.mode:
+ # There was a bug where --skip-string-normalization wouldn't stop us
+ # from normalizing docstring prefixes. To maintain stability, we can
+ # only address this buggy behaviour while the preview style is enabled.
+ if self.mode.string_normalization:
+ docstring = normalize_string_prefix(leaf.value)
+ # visit_default() does handle string normalization for us, but
+ # since this method acts differently depending on quote style (ex.
+ # see padding logic below), there's a possibility for unstable
+ # formatting as visit_default() is called *after*. To avoid a
+ # situation where this function formats a docstring differently on
+ # the second pass, normalize it early.
+ docstring = normalize_string_quotes(docstring)
+ else:
+ docstring = leaf.value
+ else:
+ # ... otherwise, we'll keep the buggy behaviour >.<
+ docstring = normalize_string_prefix(leaf.value)
prefix = get_string_prefix(docstring)
docstring = docstring[len(prefix) :] # Remove the prefix
quote_char = docstring[0]
quote_len = 1 if docstring[1] != quote_char else 3
docstring = docstring[quote_len:-quote_len]
docstring_started_empty = not docstring
+ indent = " " * 4 * self.current_line.depth
if is_multiline_string(leaf):
- indent = " " * 4 * self.current_line.depth
docstring = fix_docstring(docstring, indent)
else:
docstring = docstring.strip()
+ has_trailing_backslash = False
if docstring:
# Add some padding if the docstring starts / ends with a quote mark.
if docstring[0] == quote_char:
# Odd number of tailing backslashes, add some padding to
# avoid escaping the closing string quote.
docstring += " "
+ has_trailing_backslash = True
elif not docstring_started_empty:
docstring = " "
# We could enforce triple quotes at this point.
quote = quote_char * quote_len
- leaf.value = prefix + quote + docstring + quote
+
+ # It's invalid to put closing single-character quotes on a new line.
+ if Preview.long_docstring_quotes_on_newline in self.mode and quote_len == 3:
+ # We need to find the length of the last line of the docstring
+ # to find if we can add the closing quotes to the line without
+ # exceeding the maximum line length.
+ # If docstring is one line, we don't put the closing quotes on a
+ # separate line because it looks ugly (#3320).
+ lines = docstring.splitlines()
+ last_line_length = len(lines[-1]) if docstring else 0
+
+ # If adding closing quotes would cause the last line to exceed
+ # the maximum line length then put a line break before the
+ # closing quotes
+ if (
+ len(lines) > 1
+ and last_line_length + quote_len > self.mode.line_length
+ and len(indent) + quote_len <= self.mode.line_length
+ and not has_trailing_backslash
+ ):
+ leaf.value = prefix + quote + docstring + "\n" + indent + quote
+ else:
+ leaf.value = prefix + quote + docstring + quote
+ else:
+ leaf.value = prefix + quote + docstring + quote
yield from self.visit_default(leaf)
else:
self.visit_except_clause = partial(v, keywords={"except"}, parens=Ø)
self.visit_with_stmt = partial(v, keywords={"with"}, parens=Ø)
- self.visit_funcdef = partial(v, keywords={"def"}, parens=Ø)
self.visit_classdef = partial(v, keywords={"class"}, parens=Ø)
self.visit_expr_stmt = partial(v, keywords=Ø, parens=ASSIGNMENTS)
self.visit_return_stmt = partial(v, keywords={"return"}, parens={"return"})
yield line
+class _BracketSplitComponent(Enum):
+ head = auto()
+ body = auto()
+ tail = auto()
+
+
def left_hand_split(line: Line, _features: Collection[Feature] = ()) -> Iterator[Line]:
"""Split line into many lines, starting with the first matching bracket pair.
current_leaves is body_leaves
and leaf.type in CLOSING_BRACKETS
and leaf.opening_bracket is matching_bracket
+ and isinstance(matching_bracket, Leaf)
):
+ ensure_visible(leaf)
+ ensure_visible(matching_bracket)
current_leaves = tail_leaves if body_leaves else head_leaves
current_leaves.append(leaf)
if current_leaves is head_leaves:
if not matching_bracket:
raise CannotSplit("No brackets found")
- head = bracket_split_build_line(head_leaves, line, matching_bracket)
- body = bracket_split_build_line(body_leaves, line, matching_bracket, is_body=True)
- tail = bracket_split_build_line(tail_leaves, line, matching_bracket)
+ head = bracket_split_build_line(
+ head_leaves, line, matching_bracket, component=_BracketSplitComponent.head
+ )
+ body = bracket_split_build_line(
+ body_leaves, line, matching_bracket, component=_BracketSplitComponent.body
+ )
+ tail = bracket_split_build_line(
+ tail_leaves, line, matching_bracket, component=_BracketSplitComponent.tail
+ )
bracket_split_succeeded_or_raise(head, body, tail)
for result in (head, body, tail):
if result:
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.reverse()
body_leaves.reverse()
head_leaves.reverse()
- head = bracket_split_build_line(head_leaves, line, opening_bracket)
- body = bracket_split_build_line(body_leaves, line, opening_bracket, is_body=True)
- tail = bracket_split_build_line(tail_leaves, line, opening_bracket)
+ head = bracket_split_build_line(
+ head_leaves, line, opening_bracket, component=_BracketSplitComponent.head
+ )
+ body = bracket_split_build_line(
+ body_leaves, line, opening_bracket, component=_BracketSplitComponent.body
+ )
+ tail = bracket_split_build_line(
+ 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.
def bracket_split_build_line(
- leaves: List[Leaf], original: Line, opening_bracket: Leaf, *, is_body: bool = False
+ leaves: List[Leaf],
+ original: Line,
+ opening_bracket: Leaf,
+ *,
+ component: _BracketSplitComponent,
) -> Line:
"""Return a new line with given `leaves` and respective comments from `original`.
- If `is_body` is True, the result line is one-indented inside brackets and as such
- has its first leaf's prefix normalized and a trailing comma added when expected.
+ If it's the head component, brackets will be tracked so trailing commas are
+ respected.
+
+ If it's the body component, the result line is one-indented inside brackets and as
+ such has its first leaf's prefix normalized and a trailing comma added when
+ expected.
"""
result = Line(mode=original.mode, depth=original.depth)
- if is_body:
+ if component is _BracketSplitComponent.body:
result.inside_brackets = True
result.depth += 1
if leaves:
leaves.insert(i + 1, new_comma)
break
+ leaves_to_track: Set[LeafID] = set()
+ if (
+ Preview.handle_trailing_commas_in_head in original.mode
+ and component is _BracketSplitComponent.head
+ ):
+ leaves_to_track = get_leaves_inside_matching_brackets(leaves)
# Populate the line
for leaf in leaves:
- result.append(leaf, preformatted=True)
+ result.append(
+ leaf,
+ preformatted=True,
+ track_bracket=id(leaf) in leaves_to_track,
+ )
for comment_after in original.comments_after(leaf):
result.append(comment_after, preformatted=True)
- if is_body and should_split_line(result, opening_bracket):
+ if component is _BracketSplitComponent.body and should_split_line(
+ result, opening_bracket
+ ):
result.should_split_rhs = True
return result
node.insert_child(index, Leaf(token.LPAR, ""))
node.append_child(Leaf(token.RPAR, ""))
break
+ elif (
+ index == 1
+ and child.type == token.STAR
+ and node.type == syms.except_clause
+ ):
+ # In except* (PEP 654), the star is actually part of
+ # of the keyword. So we need to skip the insertion of
+ # invisible parentheses to work more precisely.
+ continue
elif not (isinstance(child, Leaf) and is_multiline_string(child)):
wrap_in_parentheses(node, child, visible=False)
)
+def remove_await_parens(node: Node) -> None:
+ if node.children[0].type == token.AWAIT and len(node.children) > 1:
+ if (
+ node.children[1].type == syms.atom
+ and node.children[1].children[0].type == token.LPAR
+ ):
+ if maybe_make_parens_invisible_in_atom(
+ node.children[1],
+ parent=node,
+ remove_brackets_around_comma=True,
+ ):
+ wrap_in_parentheses(node, node.children[1], visible=False)
+
+ # Since await is an expression we shouldn't remove
+ # brackets in cases where this would change
+ # the AST due to operator precedence.
+ # Therefore we only aim to remove brackets around
+ # power nodes that aren't also await expressions themselves.
+ # https://peps.python.org/pep-0492/#updated-operator-precedence-table
+ # N.B. We've still removed any redundant nested brackets though :)
+ opening_bracket = cast(Leaf, node.children[1].children[0])
+ closing_bracket = cast(Leaf, node.children[1].children[-1])
+ bracket_contents = cast(Node, node.children[1].children[1])
+ if bracket_contents.type != syms.power:
+ ensure_visible(opening_bracket)
+ ensure_visible(closing_bracket)
+ elif (
+ bracket_contents.type == syms.power
+ and bracket_contents.children[0].type == token.AWAIT
+ ):
+ ensure_visible(opening_bracket)
+ ensure_visible(closing_bracket)
+ # If we are in a nested await then recurse down.
+ remove_await_parens(bracket_contents)
+
+
def remove_with_parens(node: Node, parent: Node) -> None:
"""Recursively hide optional parens in `with` statements."""
# Removing all unnecessary parentheses in with statements in one pass is a tad
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