X-Git-Url: https://git.madduck.net/etc/vim.git/blobdiff_plain/f2ea461e9e9fa5c47bb61fd72d512c748928badc..b517dfb396a82ef263f0d366c4dc107451cf0c3c:/src/black/linegen.py?ds=inline diff --git a/src/black/linegen.py b/src/black/linegen.py index 2e16b6f..ac60ed1 100644 --- a/src/black/linegen.py +++ b/src/black/linegen.py @@ -5,12 +5,11 @@ from functools import partial, wraps import sys from typing import Collection, Iterator, List, Optional, Set, Union -from dataclasses import dataclass, field - -from black.nodes import WHITESPACE, STATEMENT, STANDALONE_COMMENT +from black.nodes import WHITESPACE, RARROW, STATEMENT, STANDALONE_COMMENT from black.nodes import ASSIGNMENTS, OPENING_BRACKETS, CLOSING_BRACKETS from black.nodes import Visitor, syms, first_child_is_arith, ensure_visible from black.nodes import is_docstring, is_empty_tuple, is_one_tuple, is_one_tuple_between +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 @@ -22,10 +21,9 @@ 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 -from black.trans import StringSplitter, StringParenWrapper, StringParenStripper -from black.mode import Mode -from black.mode import Feature +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 blib2to3.pgen2 import token @@ -40,7 +38,8 @@ class CannotSplit(CannotTransform): """A readable split that fits the allotted line length is impossible.""" -@dataclass +# This isn't a dataclass because @dataclass + Generic breaks mypyc. +# See also https://github.com/mypyc/mypyc/issues/827. class LineGenerator(Visitor[Line]): """Generates reformatted Line objects. Empty lines are not emitted. @@ -48,9 +47,10 @@ class LineGenerator(Visitor[Line]): in ways that will no longer stringify to valid Python code on the tree. """ - mode: Mode - remove_u_prefix: bool = False - current_line: Line = field(init=False) + def __init__(self, mode: Mode) -> None: + self.mode = mode + self.current_line: Line + self.__post_init__() def line(self, indent: int = 0) -> Iterator[Line]: """Generate a line. @@ -90,9 +90,7 @@ class LineGenerator(Visitor[Line]): normalize_prefix(node, inside_brackets=any_open_brackets) if self.mode.string_normalization and node.type == token.STRING: - node.value = normalize_string_prefix( - node.value, remove_u_prefix=self.remove_u_prefix - ) + node.value = normalize_string_prefix(node.value) node.value = normalize_string_quotes(node.value) if node.type == token.NUMBER: normalize_numeric_literal(node) @@ -126,7 +124,7 @@ class LineGenerator(Visitor[Line]): """Visit a statement. This implementation is shared for `if`, `while`, `for`, `try`, `except`, - `def`, `with`, `class`, `assert` and assignments. + `def`, `with`, `class`, `assert`, and assignments. The relevant Python language `keywords` for a given statement will be NAME leaves within it. This methods puts those on a separate line. @@ -136,11 +134,19 @@ class LineGenerator(Visitor[Line]): """ normalize_invisible_parens(node, parens_after=parens) for child in node.children: - if child.type == token.NAME and child.value in keywords: # type: ignore + if is_name_token(child) and child.value in keywords: yield from self.line() 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()) + + yield from self.line() + for child in node.children: + yield from self.visit(child) + def visit_suite(self, node: Node) -> Iterator[Line]: """Visit a suite.""" if self.mode.is_pyi and is_stub_suite(node): @@ -226,8 +232,9 @@ class LineGenerator(Visitor[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. - prefix = get_string_prefix(leaf.value) - docstring = leaf.value[len(prefix) :] # Remove the prefix + docstring = normalize_string_prefix(leaf.value) + prefix = get_string_prefix(docstring) + docstring = docstring[len(prefix) :] # Remove the prefix quote_char = docstring[0] # A natural way to remove the outer quotes is to do: # docstring = docstring.strip(quote_char) @@ -236,6 +243,7 @@ class LineGenerator(Visitor[Line]): # characters but only if they are the same as the first. quote_len = 1 if docstring[1] != quote_char else 3 docstring = docstring[quote_len:-quote_len] + docstring_started_empty = not docstring if is_multiline_string(leaf): indent = " " * 4 * self.current_line.depth @@ -255,8 +263,7 @@ class LineGenerator(Visitor[Line]): # Odd number of tailing backslashes, add some padding to # avoid escaping the closing string quote. docstring += " " - else: - # Add some padding if the docstring is empty. + elif not docstring_started_empty: docstring = " " # We could enforce triple quotes at this point. @@ -291,6 +298,10 @@ class LineGenerator(Visitor[Line]): self.visit_async_funcdef = self.visit_async_stmt self.visit_decorated = self.visit_decorators + # PEP 634 + self.visit_match_stmt = self.visit_match_case + self.visit_case_block = self.visit_match_case + def transform_line( line: Line, mode: Mode, features: Collection[Feature] = () @@ -326,7 +337,7 @@ def transform_line( and not (line.inside_brackets and line.contains_standalone_comments()) ): # Only apply basic string preprocessing, since lines shouldn't be split here. - if mode.experimental_string_processing: + if Preview.string_processing in mode: transformers = [string_merge, string_paren_strip] else: transformers = [] @@ -334,7 +345,9 @@ def transform_line( transformers = [left_hand_split] else: - def rhs(line: Line, features: Collection[Feature]) -> Iterator[Line]: + def _rhs( + self: object, line: Line, features: Collection[Feature] + ) -> Iterator[Line]: """Wraps calls to `right_hand_split`. The calls increasingly `omit` right-hand trailers (bracket pairs with @@ -361,7 +374,13 @@ def transform_line( line, line_length=mode.line_length, features=features ) - if mode.experimental_string_processing: + # HACK: nested functions (like _rhs) compiled by mypyc don't retain their + # __name__ attribute which is needed in `run_transformer` further down. + # Unfortunately a nested class breaks mypyc too. So a class must be created + # via type ... https://github.com/mypyc/mypyc/issues/884 + rhs = type("rhs", (), {"__call__": _rhs})() + + if Preview.string_processing in mode: if line.inside_brackets: transformers = [ string_merge, @@ -385,6 +404,9 @@ def transform_line( transformers = [delimiter_split, standalone_comment_split, rhs] else: transformers = [rhs] + # It's always safe to attempt hugging of power operations and pretty much every line + # could match. + transformers.append(hug_power_op) for transform in transformers: # We are accumulating lines in `result` because we might want to abort @@ -502,14 +524,14 @@ def right_hand_split( yield from right_hand_split(line, line_length, features=features, omit=omit) return - except CannotSplit: + except CannotSplit as e: if not ( can_be_split(body) or is_line_short_enough(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(): raise CannotSplit( @@ -517,7 +539,7 @@ def right_hand_split( " satisfy the splitting algorithm because the head or the tail" " contains multiline strings which by definition never fit one" " line." - ) + ) from e ensure_visible(opening_bracket) ensure_visible(closing_bracket) @@ -573,6 +595,20 @@ def bracket_split_build_line( original.is_def and opening_bracket.value == "(" and not any(leaf.type == token.COMMA for leaf in leaves) + # In particular, don't add one within a parenthesized return annotation. + # Unfortunately the indicator we're in a return annotation (RARROW) may + # be defined directly in the parent node, the parent of the parent ... + # and so on depending on how complex the return annotation is. + # This isn't perfect and there's some false negatives but they are in + # contexts were a comma is actually fine. + and not any( + node.prev_sibling.type == RARROW + for node in ( + leaves[0].parent, + getattr(leaves[0].parent, "parent", None), + ) + if isinstance(node, Node) and isinstance(node.prev_sibling, Leaf) + ) ) if original.is_import or no_commas: @@ -620,13 +656,13 @@ def delimiter_split(line: Line, features: Collection[Feature] = ()) -> Iterator[ try: last_leaf = line.leaves[-1] except IndexError: - raise CannotSplit("Line empty") + raise CannotSplit("Line empty") from None bt = line.bracket_tracker try: delimiter_priority = bt.max_delimiter_priority(exclude={id(last_leaf)}) except ValueError: - raise CannotSplit("No delimiters found") + raise CannotSplit("No delimiters found") from None if delimiter_priority == DOT_PRIORITY: if bt.delimiter_count_with_priority(delimiter_priority) == 1: @@ -777,10 +813,11 @@ def normalize_invisible_parens(node: Node, parens_after: Set[str]) -> None: elif node.type == syms.import_from: # "import from" nodes store parentheses directly as part of # the statement - if child.type == token.LPAR: + if is_lpar_token(child): + assert is_rpar_token(node.children[-1]) # make parentheses invisible - child.value = "" # type: ignore - node.children[-1].value = "" # type: ignore + child.value = "" + node.children[-1].value = "" elif child.type != token.STAR: # insert invisible parentheses node.insert_child(index, Leaf(token.LPAR, "")) @@ -825,11 +862,11 @@ def maybe_make_parens_invisible_in_atom(node: LN, parent: LN) -> bool: first = node.children[0] last = node.children[-1] - if first.type == token.LPAR and last.type == token.RPAR: + if is_lpar_token(first) and is_rpar_token(last): middle = node.children[1] # make parentheses invisible - first.value = "" # type: ignore - last.value = "" # type: ignore + first.value = "" + last.value = "" maybe_make_parens_invisible_in_atom(middle, parent=parent) if is_atom_with_invisible_parens(middle): @@ -905,6 +942,7 @@ def generate_trailers_to_omit(line: Line, line_length: int) -> Iterator[Set[Leaf if ( prev and prev.type == token.COMMA + and leaf.opening_bracket is not None and not is_one_tuple_between( leaf.opening_bracket, leaf, line.leaves ) @@ -932,6 +970,7 @@ def generate_trailers_to_omit(line: Line, line_length: int) -> Iterator[Set[Leaf if ( prev and prev.type == token.COMMA + and leaf.opening_bracket is not None and not is_one_tuple_between(leaf.opening_bracket, leaf, line.leaves) ): # Never omit bracket pairs with trailing commas. @@ -960,14 +999,19 @@ def run_transformer( result.extend(transform_line(transformed_line, mode=mode, features=features)) - if not ( - transform.__name__ == "rhs" - and line.bracket_tracker.invisible - and not any(bracket.value for bracket in line.bracket_tracker.invisible) - and not line.contains_multiline_strings() - and not result[0].contains_uncollapsable_type_comments() - and not result[0].contains_unsplittable_type_ignore() - and not is_line_short_enough(result[0], line_length=mode.line_length) + if ( + 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() + or result[0].contains_uncollapsable_type_comments() + or result[0].contains_unsplittable_type_ignore() + or is_line_short_enough(result[0], line_length=mode.line_length) + # If any leaves have no parents (which _can_ occur since + # `transform(line)` potentially destroys the line's underlying node + # structure), then we can't proceed. Doing so would cause the below + # call to `append_leaves()` to fail. + or any(leaf.parent is None for leaf in line.leaves) ): return result