X-Git-Url: https://git.madduck.net/etc/vim.git/blobdiff_plain/8091b2503d12dd0110e0f1a9ed1e6b830aa668ed..c160e4b7ce30c661ac4f2dfa5038becf1b8c5c33:/src/black/lines.py diff --git a/src/black/lines.py b/src/black/lines.py index 08281bc..0a307b4 100644 --- a/src/black/lines.py +++ b/src/black/lines.py @@ -1,4 +1,5 @@ import itertools +import math import sys from dataclasses import dataclass, field from typing import ( @@ -10,10 +11,11 @@ from typing import ( Sequence, Tuple, TypeVar, + Union, cast, ) -from black.brackets import DOT_PRIORITY, BracketTracker +from black.brackets import COMMA_PRIORITY, DOT_PRIORITY, BracketTracker from black.mode import Mode, Preview from black.nodes import ( BRACKETS, @@ -26,10 +28,13 @@ from black.nodes import ( is_multiline_string, is_one_sequence_between, is_type_comment, + is_type_ignore_comment, + is_with_or_async_with_stmt, replace_child, syms, whitespace, ) +from black.strings import str_width from blib2to3.pgen2 import token from blib2to3.pytree import Leaf, Node @@ -37,13 +42,14 @@ from blib2to3.pytree import Leaf, Node T = TypeVar("T") Index = int LeafID = int +LN = Union[Leaf, Node] @dataclass class Line: """Holds leaves and comments. Can be printed with `str(line)`.""" - mode: Mode + mode: Mode = field(repr=False) depth: int = 0 leaves: List[Leaf] = field(default_factory=list) # keys ordered like `leaves` @@ -119,6 +125,11 @@ class Line: """Is this an import line?""" return bool(self) and is_import(self.leaves[0]) + @property + def is_with_or_async_with_stmt(self) -> bool: + """Is this a with_stmt line?""" + return bool(self) and is_with_or_async_with_stmt(self.leaves[0]) + @property def is_class(self) -> bool: """Is this line a class definition?""" @@ -154,6 +165,13 @@ class Line: and second_leaf.value == "def" ) + @property + def is_stub_def(self) -> bool: + """Is this line a function definition with a body consisting only of "..."?""" + return self.is_def and self.leaves[-4:] == [Leaf(token.COLON, ":")] + [ + Leaf(token.DOT, ".") for _ in range(3) + ] + @property def is_class_paren_empty(self) -> bool: """Is this a class with no base classes but using parentheses? @@ -186,6 +204,26 @@ class Line: return False return self.leaves[-1].type == token.COLON + def is_fmt_pass_converted( + self, *, first_leaf_matches: Optional[Callable[[Leaf], bool]] = None + ) -> bool: + """Is this line converted from fmt off/skip code? + + If first_leaf_matches is not None, it only returns True if the first + leaf of converted code matches. + """ + if len(self.leaves) != 1: + return False + leaf = self.leaves[0] + if ( + leaf.type != STANDALONE_COMMENT + or leaf.fmt_pass_converted_first_leaf is None + ): + return False + return first_leaf_matches is None or first_leaf_matches( + leaf.fmt_pass_converted_first_leaf + ) + def contains_standalone_comments(self, depth_limit: int = sys.maxsize) -> bool: """If so, needs to be split before emitting.""" for leaf in self.leaves: @@ -221,7 +259,7 @@ class Line: for comment in comments: if is_type_comment(comment): if comment_seen or ( - not is_type_comment(comment, " ignore") + not is_type_ignore_comment(comment) and leaf_id not in ignored_ids ): return True @@ -258,7 +296,7 @@ class Line: # line. for node in self.leaves[-2:]: for comment in self.comments.get(id(node), []): - if is_type_comment(comment, " ignore"): + if is_type_ignore_comment(comment): return True return False @@ -275,8 +313,7 @@ class Line: - it's not a single-element subscript Additionally, if ensure_removable: - it's not from square bracket indexing - (specifically, single-element square bracket indexing with - Preview.skip_magic_trailing_comma_in_subscript) + (specifically, single-element square bracket indexing) """ if not ( closing.type in CLOSING_BRACKETS @@ -290,8 +327,7 @@ class Line: if closing.type == token.RSQB: if ( - Preview.one_element_subscript in self.mode - and closing.parent + closing.parent and closing.parent.type == syms.trailer and closing.opening_bracket and is_one_sequence_between( @@ -309,18 +345,16 @@ class Line: comma = self.leaves[-1] if comma.parent is None: return False - if Preview.skip_magic_trailing_comma_in_subscript in self.mode: - return ( - comma.parent.type != syms.subscriptlist - or closing.opening_bracket is None - or not is_one_sequence_between( - closing.opening_bracket, - closing, - self.leaves, - brackets=(token.LSQB, token.RSQB), - ) + return ( + comma.parent.type != syms.subscriptlist + or closing.opening_bracket is None + or not is_one_sequence_between( + closing.opening_bracket, + closing, + self.leaves, + brackets=(token.LSQB, token.RSQB), ) - return comma.parent.type == syms.listmaker + ) if self.is_import: return True @@ -450,6 +484,17 @@ class Line: return bool(self.leaves or self.comments) +@dataclass +class RHSResult: + """Intermediate split result from a right hand split.""" + + head: Line + body: Line + tail: Line + opening_bracket: Leaf + closing_bracket: Leaf + + @dataclass class LinesBlock: """Class that holds information about a block of formatted lines. @@ -485,7 +530,7 @@ class EmptyLineTracker: mode: Mode previous_line: Optional[Line] = None previous_block: Optional[LinesBlock] = None - previous_defs: List[int] = field(default_factory=list) + previous_defs: List[Line] = field(default_factory=list) semantic_leading_comment: Optional[LinesBlock] = None def maybe_empty_lines(self, current_line: Line) -> LinesBlock: @@ -520,7 +565,8 @@ class EmptyLineTracker: and (self.semantic_leading_comment is None or before) ): self.semantic_leading_comment = block - elif not current_line.is_decorator: + # `or before` means this decorator already has an empty line before + elif not current_line.is_decorator or before: self.semantic_leading_comment = None self.previous_line = current_line @@ -539,13 +585,26 @@ class EmptyLineTracker: first_leaf.prefix = "" else: before = 0 + + user_had_newline = bool(before) depth = current_line.depth - while self.previous_defs and self.previous_defs[-1] >= depth: + + previous_def = None + while self.previous_defs and self.previous_defs[-1].depth >= depth: + previous_def = self.previous_defs.pop() + + if previous_def is not None: + assert self.previous_line is not None if self.mode.is_pyi: - assert self.previous_line is not None if depth and not current_line.is_def and self.previous_line.is_def: # Empty lines between attributes and methods should be preserved. - before = min(1, before) + before = 1 if user_had_newline else 0 + elif ( + Preview.blank_line_after_nested_stub_class in self.mode + and previous_def.is_class + and not previous_def.is_stub_class + ): + before = 1 elif depth: before = 0 else: @@ -555,7 +614,7 @@ class EmptyLineTracker: before = 1 elif ( not depth - and self.previous_defs[-1] + and previous_def.depth and current_line.leaves[-1].type == token.COLON and ( current_line.leaves[0].value @@ -572,14 +631,17 @@ class EmptyLineTracker: before = 1 else: before = 2 - self.previous_defs.pop() + if current_line.is_decorator or current_line.is_def or current_line.is_class: - return self._maybe_empty_lines_for_class_or_def(current_line, before) + return self._maybe_empty_lines_for_class_or_def( + current_line, before, user_had_newline + ) if ( self.previous_line and self.previous_line.is_import and not current_line.is_import + and not current_line.is_fmt_pass_converted(first_leaf_matches=is_import) and depth == self.previous_line.depth ): return (before or 1), 0 @@ -589,21 +651,19 @@ class EmptyLineTracker: and self.previous_line.is_class and current_line.is_triple_quoted_string ): + if Preview.no_blank_line_before_class_docstring in current_line.mode: + return 0, 1 return before, 1 - if ( - Preview.remove_block_trailing_newline in current_line.mode - and self.previous_line - and self.previous_line.opens_block - ): + if self.previous_line and self.previous_line.opens_block: return 0, 0 return before, 0 - def _maybe_empty_lines_for_class_or_def( - self, current_line: Line, before: int + def _maybe_empty_lines_for_class_or_def( # noqa: C901 + self, current_line: Line, before: int, user_had_newline: bool ) -> Tuple[int, int]: if not current_line.is_decorator: - self.previous_defs.append(current_line.depth) + self.previous_defs.append(current_line) if self.previous_line is None: # Don't insert empty lines before the first line in the file. return 0, 0 @@ -628,9 +688,7 @@ class EmptyLineTracker: ): slc = self.semantic_leading_comment if ( - Preview.empty_lines_before_class_or_def_with_leading_comments - in current_line.mode - and slc is not None + slc is not None and slc.previous_block is not None and not slc.previous_block.original_line.is_class and not slc.previous_block.original_line.opens_block @@ -668,6 +726,14 @@ class EmptyLineTracker: newlines = 0 else: newlines = 1 if current_line.depth else 2 + # If a user has left no space after a dummy implementation, don't insert + # new lines. This is useful for instance for @overload or Protocols. + if ( + Preview.dummy_implementations in self.mode + and self.previous_line.is_stub_def + and not user_had_newline + ): + newlines = 0 if comment_to_add_newlines is not None: previous_block = comment_to_add_newlines.previous_block if previous_block is not None: @@ -710,18 +776,95 @@ def append_leaves( new_line.append(comment_leaf, preformatted=True) -def is_line_short_enough(line: Line, *, line_length: int, line_str: str = "") -> bool: - """Return True if `line` is no longer than `line_length`. - +def is_line_short_enough( # noqa: C901 + line: Line, *, mode: Mode, line_str: str = "" +) -> bool: + """For non-multiline strings, return True if `line` is no longer than `line_length`. + For multiline strings, looks at the context around `line` to determine + if it should be inlined or split up. Uses the provided `line_str` rendering, if any, otherwise computes a new one. """ if not line_str: line_str = line_to_string(line) - return ( - len(line_str) <= line_length - and "\n" not in line_str # multiline strings - and not line.contains_standalone_comments() - ) + + width = str_width if mode.preview else len + + if Preview.multiline_string_handling not in mode: + return ( + width(line_str) <= mode.line_length + and "\n" not in line_str # multiline strings + and not line.contains_standalone_comments() + ) + + if line.contains_standalone_comments(): + return False + if "\n" not in line_str: + # No multiline strings (MLS) present + return width(line_str) <= mode.line_length + + first, *_, last = line_str.split("\n") + if width(first) > mode.line_length or width(last) > mode.line_length: + return False + + # Traverse the AST to examine the context of the multiline string (MLS), + # tracking aspects such as depth and comma existence, + # to determine whether to split the MLS or keep it together. + # Depth (which is based on the existing bracket_depth concept) + # is needed to determine nesting level of the MLS. + # Includes special case for trailing commas. + commas: List[int] = [] # tracks number of commas per depth level + multiline_string: Optional[Leaf] = None + # store the leaves that contain parts of the MLS + multiline_string_contexts: List[LN] = [] + + max_level_to_update: Union[int, float] = math.inf # track the depth of the MLS + for i, leaf in enumerate(line.leaves): + if max_level_to_update == math.inf: + had_comma: Optional[int] = None + if leaf.bracket_depth + 1 > len(commas): + commas.append(0) + elif leaf.bracket_depth + 1 < len(commas): + had_comma = commas.pop() + if ( + had_comma is not None + and multiline_string is not None + and multiline_string.bracket_depth == leaf.bracket_depth + 1 + ): + # Have left the level with the MLS, stop tracking commas + max_level_to_update = leaf.bracket_depth + if had_comma > 0: + # MLS was in parens with at least one comma - force split + return False + + if leaf.bracket_depth <= max_level_to_update and leaf.type == token.COMMA: + # Ignore non-nested trailing comma + # directly after MLS/MLS-containing expression + ignore_ctxs: List[Optional[LN]] = [None] + ignore_ctxs += multiline_string_contexts + if not (leaf.prev_sibling in ignore_ctxs and i == len(line.leaves) - 1): + commas[leaf.bracket_depth] += 1 + if max_level_to_update != math.inf: + max_level_to_update = min(max_level_to_update, leaf.bracket_depth) + + if is_multiline_string(leaf): + if len(multiline_string_contexts) > 0: + # >1 multiline string cannot fit on a single line - force split + return False + multiline_string = leaf + ctx: LN = leaf + # fetch the leaf components of the MLS in the AST + while str(ctx) in line_str: + multiline_string_contexts.append(ctx) + if ctx.parent is None: + break + ctx = ctx.parent + + # May not have a triple-quoted multiline string at all, + # in case of a regular string with embedded newlines and line continuations + if len(multiline_string_contexts) == 0: + return True + + return all(val == 0 for val in commas) def can_be_split(line: Line) -> bool: @@ -761,25 +904,42 @@ def can_be_split(line: Line) -> bool: def can_omit_invisible_parens( - line: Line, + rhs: RHSResult, line_length: int, ) -> bool: - """Does `line` have a shape safe to reformat without optional parens around it? + """Does `rhs.body` have a shape safe to reformat without optional parens around it? Returns True for only a subset of potentially nice looking formattings but the point is to not return false positives that end up producing lines that are too long. """ + line = rhs.body bt = line.bracket_tracker if not bt.delimiters: # Without delimiters the optional parentheses are useless. return True max_priority = bt.max_delimiter_priority() - if bt.delimiter_count_with_priority(max_priority) > 1: + delimiter_count = bt.delimiter_count_with_priority(max_priority) + if delimiter_count > 1: # With more than one delimiter of a kind the optional parentheses read better. return False + if delimiter_count == 1: + if ( + Preview.wrap_multiple_context_managers_in_parens in line.mode + and max_priority == COMMA_PRIORITY + and rhs.head.is_with_or_async_with_stmt + ): + # For two context manager with statements, the optional parentheses read + # better. In this case, `rhs.body` is the context managers part of + # the with statement. `rhs.head` is the `with (` part on the previous + # line. + return False + # Otherwise it may also read better, but we don't do it today and requires + # careful considerations for all possible cases. See + # https://github.com/psf/black/issues/2156. + if max_priority == DOT_PRIORITY: # A single stranded method call doesn't require optional parentheses. return True