X-Git-Url: https://git.madduck.net/etc/vim.git/blobdiff_plain/117891878e5be4d6b771ae5de299e51b679cea27..a44dc3d59eb46901f9fe893727280903df41fc20:/src/black/trans.py?ds=inline diff --git a/src/black/trans.py b/src/black/trans.py index d918ef1..a5cf495 100644 --- a/src/black/trans.py +++ b/src/black/trans.py @@ -1,10 +1,11 @@ """ String transformers that can split and merge strings. """ +import re +import sys from abc import ABC, abstractmethod from collections import defaultdict from dataclasses import dataclass -import regex as re from typing import ( Any, Callable, @@ -21,29 +22,38 @@ from typing import ( TypeVar, Union, ) -import sys if sys.version_info < (3, 8): - from typing_extensions import Final + from typing_extensions import Final, Literal else: - from typing import Final + from typing import Literal, Final from mypy_extensions import trait -from black.rusty import Result, Ok, Err - -from black.mode import Feature -from black.nodes import syms, replace_child, parent_type -from black.nodes import is_empty_par, is_empty_lpar, is_empty_rpar -from black.nodes import OPENING_BRACKETS, CLOSING_BRACKETS, STANDALONE_COMMENT -from black.lines import Line, append_leaves -from black.brackets import BracketMatchError from black.comments import contains_pragma_comment -from black.strings import has_triple_quotes, get_string_prefix, assert_is_leaf_string -from black.strings import normalize_string_quotes - -from blib2to3.pytree import Leaf, Node +from black.lines import Line, append_leaves +from black.mode import Feature +from black.nodes import ( + CLOSING_BRACKETS, + OPENING_BRACKETS, + STANDALONE_COMMENT, + is_empty_lpar, + is_empty_par, + is_empty_rpar, + is_part_of_annotation, + parent_type, + replace_child, + syms, +) +from black.rusty import Err, Ok, Result +from black.strings import ( + assert_is_leaf_string, + get_string_prefix, + has_triple_quotes, + normalize_string_quotes, +) from blib2to3.pgen2 import token +from blib2to3.pytree import Leaf, Node class CannotTransform(Exception): @@ -71,6 +81,84 @@ def TErr(err_msg: str) -> Err[CannotTransform]: return Err(cant_transform) +def hug_power_op(line: Line, features: Collection[Feature]) -> Iterator[Line]: + """A transformer which normalizes spacing around power operators.""" + + # Performance optimization to avoid unnecessary Leaf clones and other ops. + for leaf in line.leaves: + if leaf.type == token.DOUBLESTAR: + break + else: + raise CannotTransform("No doublestar token was found in the line.") + + def is_simple_lookup(index: int, step: Literal[1, -1]) -> bool: + # Brackets and parentheses indicate calls, subscripts, etc. ... + # basically stuff that doesn't count as "simple". Only a NAME lookup + # or dotted lookup (eg. NAME.NAME) is OK. + if step == -1: + disallowed = {token.RPAR, token.RSQB} + else: + disallowed = {token.LPAR, token.LSQB} + + while 0 <= index < len(line.leaves): + current = line.leaves[index] + if current.type in disallowed: + return False + if current.type not in {token.NAME, token.DOT} or current.value == "for": + # If the current token isn't disallowed, we'll assume this is simple as + # only the disallowed tokens are semantically attached to this lookup + # expression we're checking. Also, stop early if we hit the 'for' bit + # of a comprehension. + return True + + index += step + + return True + + def is_simple_operand(index: int, kind: Literal["base", "exponent"]) -> bool: + # An operand is considered "simple" if's a NAME, a numeric CONSTANT, a simple + # lookup (see above), with or without a preceding unary operator. + start = line.leaves[index] + if start.type in {token.NAME, token.NUMBER}: + return is_simple_lookup(index, step=(1 if kind == "exponent" else -1)) + + if start.type in {token.PLUS, token.MINUS, token.TILDE}: + if line.leaves[index + 1].type in {token.NAME, token.NUMBER}: + # step is always one as bases with a preceding unary op will be checked + # for simplicity starting from the next token (so it'll hit the check + # above). + return is_simple_lookup(index + 1, step=1) + + return False + + new_line = line.clone() + should_hug = False + for idx, leaf in enumerate(line.leaves): + new_leaf = leaf.clone() + if should_hug: + new_leaf.prefix = "" + should_hug = False + + should_hug = ( + (0 < idx < len(line.leaves) - 1) + and leaf.type == token.DOUBLESTAR + and is_simple_operand(idx - 1, kind="base") + and line.leaves[idx - 1].value != "lambda" + and is_simple_operand(idx + 1, kind="exponent") + ) + if should_hug: + new_leaf.prefix = "" + + # We have to be careful to make a new line properly: + # - bracket related metadata must be maintained (handled by Line.append) + # - comments need to copied over, updating the leaf IDs they're attached to + new_line.append(new_leaf, preformatted=True) + for comment_leaf in line.comments_after(leaf): + new_line.append(comment_leaf, preformatted=True) + + yield new_line + + class StringTransformer(ABC): """ An implementation of the Transformer protocol that relies on its @@ -263,7 +351,7 @@ class StringMerger(StringTransformer, CustomSplitMapMixin): Requirements: (A) The line contains adjacent strings such that ALL of the validation checks - listed in StringMerger.__validate_msg(...)'s docstring pass. + listed in StringMerger._validate_msg(...)'s docstring pass. OR (B) The line contains a string which uses line continuation backslashes. @@ -283,12 +371,14 @@ class StringMerger(StringTransformer, CustomSplitMapMixin): is_valid_index = is_valid_index_factory(LL) - for (i, leaf) in enumerate(LL): + for i, leaf in enumerate(LL): if ( leaf.type == token.STRING and is_valid_index(i + 1) and LL[i + 1].type == token.STRING ): + if is_part_of_annotation(leaf): + return TErr("String is part of type annotation.") return Ok(i) if leaf.type == token.STRING and "\\\n" in leaf.value: @@ -366,7 +456,7 @@ class StringMerger(StringTransformer, CustomSplitMapMixin): Returns: Ok(new_line), if ALL of the validation checks found in - __validate_msg(...) pass. + _validate_msg(...) pass. OR Err(CannotTransform), otherwise. """ @@ -453,7 +543,7 @@ class StringMerger(StringTransformer, CustomSplitMapMixin): # with 'f'... if "f" in prefix and "f" not in next_prefix: # Then we must escape any braces contained in this substring. - SS = re.subf(r"(\{|\})", "{1}{1}", SS) + SS = re.sub(r"(\{|\})", r"\1\1", SS) NSS = make_naked(SS, next_prefix) @@ -465,6 +555,9 @@ class StringMerger(StringTransformer, CustomSplitMapMixin): next_str_idx += 1 + # Take a note on the index of the non-STRING leaf. + non_string_idx = next_str_idx + S_leaf = Leaf(token.STRING, S) if self.normalize_strings: S_leaf.value = normalize_string_quotes(S_leaf.value) @@ -484,11 +577,22 @@ class StringMerger(StringTransformer, CustomSplitMapMixin): string_leaf = Leaf(token.STRING, S_leaf.value.replace(BREAK_MARK, "")) if atom_node is not None: - replace_child(atom_node, string_leaf) + # If not all children of the atom node are merged (this can happen + # when there is a standalone comment in the middle) ... + if non_string_idx - string_idx < len(atom_node.children): + # We need to replace the old STRING leaves with the new string leaf. + first_child_idx = LL[string_idx].remove() + for idx in range(string_idx + 1, non_string_idx): + LL[idx].remove() + if first_child_idx is not None: + atom_node.insert_child(first_child_idx, string_leaf) + else: + # Else replace the atom node with the new string leaf. + replace_child(atom_node, string_leaf) # Build the final line ('new_line') that this method will later return. new_line = line.clone() - for (i, leaf) in enumerate(LL): + for i, leaf in enumerate(LL): if i == string_idx: new_line.append(string_leaf) @@ -506,7 +610,7 @@ class StringMerger(StringTransformer, CustomSplitMapMixin): def _validate_msg(line: Line, string_idx: int) -> TResult[None]: """Validate (M)erge (S)tring (G)roup - Transform-time string validation logic for __merge_string_group(...). + Transform-time string validation logic for _merge_string_group(...). Returns: * Ok(None), if ALL validation checks (listed below) pass. @@ -520,6 +624,11 @@ class StringMerger(StringTransformer, CustomSplitMapMixin): - The set of all string prefixes in the string group is of length greater than one and is not equal to {"", "f"}. - The string group consists of raw strings. + - The string group is stringified type annotations. We don't want to + process stringified type annotations since pyright doesn't support + them spanning multiple string values. (NOTE: mypy, pytype, pyre do + support them, so we can change if pyright also gains support in the + future. See https://github.com/microsoft/pyright/issues/4359.) """ # We first check for "inner" stand-alone comments (i.e. stand-alone # comments that have a string leaf before them AND after them). @@ -609,7 +718,7 @@ class StringParenStripper(StringTransformer): is_valid_index = is_valid_index_factory(LL) - for (idx, leaf) in enumerate(LL): + for idx, leaf in enumerate(LL): # Should be a string... if leaf.type != token.STRING: continue @@ -710,13 +819,7 @@ class StringParenStripper(StringTransformer): new_line = line.clone() new_line.comments = line.comments.copy() - try: - append_leaves(new_line, line, LL[: string_idx - 1]) - except BracketMatchError: - # HACK: I believe there is currently a bug somewhere in - # right_hand_split() that is causing brackets to not be tracked - # properly by a shared BracketTracker. - append_leaves(new_line, line, LL[: string_idx - 1], preformatted=True) + append_leaves(new_line, line, LL[: string_idx - 1]) string_leaf = Leaf(token.STRING, LL[string_idx].value) LL[string_idx - 1].remove() @@ -941,6 +1044,88 @@ class BaseStringSplitter(StringTransformer): max_string_length = self.line_length - offset return max_string_length + @staticmethod + def _prefer_paren_wrap_match(LL: List[Leaf]) -> Optional[int]: + """ + Returns: + string_idx such that @LL[string_idx] is equal to our target (i.e. + matched) string, if this line matches the "prefer paren wrap" statement + requirements listed in the 'Requirements' section of the StringParenWrapper + class's docstring. + OR + None, otherwise. + """ + # The line must start with a string. + if LL[0].type != token.STRING: + return None + + # If the string is surrounded by commas (or is the first/last child)... + prev_sibling = LL[0].prev_sibling + next_sibling = LL[0].next_sibling + if not prev_sibling and not next_sibling and parent_type(LL[0]) == syms.atom: + # If it's an atom string, we need to check the parent atom's siblings. + parent = LL[0].parent + assert parent is not None # For type checkers. + prev_sibling = parent.prev_sibling + next_sibling = parent.next_sibling + if (not prev_sibling or prev_sibling.type == token.COMMA) and ( + not next_sibling or next_sibling.type == token.COMMA + ): + return 0 + + return None + + +def iter_fexpr_spans(s: str) -> Iterator[Tuple[int, int]]: + """ + Yields spans corresponding to expressions in a given f-string. + Spans are half-open ranges (left inclusive, right exclusive). + Assumes the input string is a valid f-string, but will not crash if the input + string is invalid. + """ + stack: List[int] = [] # our curly paren stack + i = 0 + while i < len(s): + if s[i] == "{": + # if we're in a string part of the f-string, ignore escaped curly braces + if not stack and i + 1 < len(s) and s[i + 1] == "{": + i += 2 + continue + stack.append(i) + i += 1 + continue + + if s[i] == "}": + if not stack: + i += 1 + continue + j = stack.pop() + # we've made it back out of the expression! yield the span + if not stack: + yield (j, i + 1) + i += 1 + continue + + # if we're in an expression part of the f-string, fast forward through strings + # note that backslashes are not legal in the expression portion of f-strings + if stack: + delim = None + if s[i : i + 3] in ("'''", '"""'): + delim = s[i : i + 3] + elif s[i] in ("'", '"'): + delim = s[i] + if delim: + i += len(delim) + while i < len(s) and s[i : i + len(delim)] != delim: + i += 1 + i += len(delim) + continue + i += 1 + + +def fstring_contains_expr(s: str) -> bool: + return any(iter_fexpr_spans(s)) + class StringSplitter(BaseStringSplitter, CustomSplitMapMixin): """ @@ -981,21 +1166,13 @@ class StringSplitter(BaseStringSplitter, CustomSplitMapMixin): """ MIN_SUBSTR_SIZE: Final = 6 - # Matches an "f-expression" (e.g. {var}) that might be found in an f-string. - RE_FEXPR: Final = r""" - (? TMatchResult: LL = line.leaves + if self._prefer_paren_wrap_match(LL) is not None: + return TErr("Line needs to be wrapped in parens first.") + is_valid_index = is_valid_index_factory(LL) idx = 0 @@ -1058,15 +1235,15 @@ class StringSplitter(BaseStringSplitter, CustomSplitMapMixin): # contain any f-expressions, but ONLY if the original f-string # contains at least one f-expression. Otherwise, we will alter the AST # of the program. - drop_pointless_f_prefix = ("f" in prefix) and re.search( - self.RE_FEXPR, LL[string_idx].value, re.VERBOSE + drop_pointless_f_prefix = ("f" in prefix) and fstring_contains_expr( + LL[string_idx].value ) first_string_line = True string_op_leaves = self._get_string_operator_leaves(LL) string_op_leaves_length = ( - sum([len(str(prefix_leaf)) for prefix_leaf in string_op_leaves]) + 1 + sum(len(str(prefix_leaf)) for prefix_leaf in string_op_leaves) + 1 if string_op_leaves else 0 ) @@ -1183,9 +1360,14 @@ class StringSplitter(BaseStringSplitter, CustomSplitMapMixin): # prefix, and the current custom split did NOT originally use a # prefix... if ( - next_value != self._normalize_f_string(next_value, prefix) - and use_custom_breakpoints + use_custom_breakpoints and not csplit.has_prefix + and ( + # `next_value == prefix + QUOTE` happens when the custom + # split is an empty string. + next_value == prefix + QUOTE + or next_value != self._normalize_f_string(next_value, prefix) + ) ): # Then `csplit.break_idx` will be off by one after removing # the 'f' prefix. @@ -1299,9 +1481,7 @@ class StringSplitter(BaseStringSplitter, CustomSplitMapMixin): """ if "f" not in get_string_prefix(string).lower(): return - - for match in re.finditer(self.RE_FEXPR, string, re.VERBOSE): - yield match.span() + yield from iter_fexpr_spans(string) def _get_illegal_split_indices(self, string: str) -> Set[Index]: illegal_indices: Set[Index] = set() @@ -1417,7 +1597,7 @@ class StringSplitter(BaseStringSplitter, CustomSplitMapMixin): """ assert_is_leaf_string(string) - if "f" in prefix and not re.search(self.RE_FEXPR, string, re.VERBOSE): + if "f" in prefix and not fstring_contains_expr(string): new_prefix = prefix.replace("f", "") temp = string[len(prefix) :] @@ -1443,8 +1623,7 @@ class StringSplitter(BaseStringSplitter, CustomSplitMapMixin): class StringParenWrapper(BaseStringSplitter, CustomSplitMapMixin): """ - StringTransformer that splits non-"atom" strings (i.e. strings that do not - exist on lines by themselves). + StringTransformer that wraps strings in parens and then splits at the LPAR. Requirements: All of the requirements listed in BaseStringSplitter's docstring in @@ -1464,6 +1643,12 @@ class StringParenWrapper(BaseStringSplitter, CustomSplitMapMixin): OR * The line is a dictionary key assignment where some valid key is being assigned the value of some string. + OR + * The line is an lambda expression and the value is a string. + OR + * The line starts with an "atom" string that prefers to be wrapped in + parens. It's preferred to be wrapped when the string is surrounded by + commas (or is the first/last child). Transformations: The chosen string is wrapped in parentheses and then split at the LPAR. @@ -1488,6 +1673,9 @@ class StringParenWrapper(BaseStringSplitter, CustomSplitMapMixin): changed such that it no longer needs to be given its own line, StringParenWrapper relies on StringParenStripper to clean up the parentheses it created. + + For "atom" strings that prefers to be wrapped in parens, it requires + StringSplitter to hold the split until the string is wrapped in parens. """ def do_splitter_match(self, line: Line) -> TMatchResult: @@ -1503,7 +1691,8 @@ class StringParenWrapper(BaseStringSplitter, CustomSplitMapMixin): or self._else_match(LL) or self._assert_match(LL) or self._assign_match(LL) - or self._dict_match(LL) + or self._dict_or_lambda_match(LL) + or self._prefer_paren_wrap_match(LL) ) if string_idx is not None: @@ -1593,7 +1782,7 @@ class StringParenWrapper(BaseStringSplitter, CustomSplitMapMixin): if parent_type(LL[0]) == syms.assert_stmt and LL[0].value == "assert": is_valid_index = is_valid_index_factory(LL) - for (i, leaf) in enumerate(LL): + for i, leaf in enumerate(LL): # We MUST find a comma... if leaf.type == token.COMMA: idx = i + 2 if is_empty_par(LL[i + 1]) else i + 1 @@ -1631,7 +1820,7 @@ class StringParenWrapper(BaseStringSplitter, CustomSplitMapMixin): ): is_valid_index = is_valid_index_factory(LL) - for (i, leaf) in enumerate(LL): + for i, leaf in enumerate(LL): # We MUST find either an '=' or '+=' symbol... if leaf.type in [token.EQUAL, token.PLUSEQUAL]: idx = i + 2 if is_empty_par(LL[i + 1]) else i + 1 @@ -1660,22 +1849,23 @@ class StringParenWrapper(BaseStringSplitter, CustomSplitMapMixin): return None @staticmethod - def _dict_match(LL: List[Leaf]) -> Optional[int]: + def _dict_or_lambda_match(LL: List[Leaf]) -> Optional[int]: """ Returns: string_idx such that @LL[string_idx] is equal to our target (i.e. matched) string, if this line matches the dictionary key assignment - statement requirements listed in the 'Requirements' section of this - classes' docstring. + statement or lambda expression requirements listed in the + 'Requirements' section of this classes' docstring. OR None, otherwise. """ - # If this line is apart of a dictionary key assignment... - if syms.dictsetmaker in [parent_type(LL[0]), parent_type(LL[0].parent)]: + # If this line is a part of a dictionary key assignment or lambda expression... + parent_types = [parent_type(LL[0]), parent_type(LL[0].parent)] + if syms.dictsetmaker in parent_types or syms.lambdef in parent_types: is_valid_index = is_valid_index_factory(LL) - for (i, leaf) in enumerate(LL): - # We MUST find a colon... + for i, leaf in enumerate(LL): + # We MUST find a colon, it can either be dict's or lambda's colon... if leaf.type == token.COLON: idx = i + 2 if is_empty_par(LL[i + 1]) else i + 1 @@ -1770,6 +1960,25 @@ class StringParenWrapper(BaseStringSplitter, CustomSplitMapMixin): f" (left_leaves={left_leaves}, right_leaves={right_leaves})" ) old_rpar_leaf = right_leaves.pop() + elif right_leaves and right_leaves[-1].type == token.RPAR: + # Special case for lambda expressions as dict's value, e.g.: + # my_dict = { + # "key": lambda x: f"formatted: {x}, + # } + # After wrapping the dict's value with parentheses, the string is + # followed by a RPAR but its opening bracket is lambda's, not + # the string's: + # "key": (lambda x: f"formatted: {x}), + opening_bracket = right_leaves[-1].opening_bracket + if opening_bracket is not None and opening_bracket in left_leaves: + index = left_leaves.index(opening_bracket) + if ( + index > 0 + and index < len(left_leaves) - 1 + and left_leaves[index - 1].type == token.COLON + and left_leaves[index + 1].value == "lambda" + ): + right_leaves.pop() append_leaves(string_line, line, right_leaves)