X-Git-Url: https://git.madduck.net/etc/vim.git/blobdiff_plain/99b68e59ce0424a86215cc9ca0cb46e481d2a6fe..117891878e5be4d6b771ae5de299e51b679cea27:/src/black/trans.py diff --git a/src/black/trans.py b/src/black/trans.py index 4fb2c4d..d918ef1 100644 --- a/src/black/trans.py +++ b/src/black/trans.py @@ -8,6 +8,7 @@ import regex as re from typing import ( Any, Callable, + ClassVar, Collection, Dict, Iterable, @@ -15,10 +16,19 @@ from typing import ( List, Optional, Sequence, + Set, Tuple, TypeVar, Union, ) +import sys + +if sys.version_info < (3, 8): + from typing_extensions import Final +else: + from typing import Final + +from mypy_extensions import trait from black.rusty import Result, Ok, Err @@ -61,7 +71,6 @@ def TErr(err_msg: str) -> Err[CannotTransform]: return Err(cant_transform) -@dataclass # type: ignore class StringTransformer(ABC): """ An implementation of the Transformer protocol that relies on its @@ -89,9 +98,13 @@ class StringTransformer(ABC): as much as possible. """ - line_length: int - normalize_strings: bool - __name__ = "StringTransformer" + __name__: Final = "StringTransformer" + + # Ideally this would be a dataclass, but unfortunately mypyc breaks when used with + # `abc.ABC`. + def __init__(self, line_length: int, normalize_strings: bool) -> None: + self.line_length = line_length + self.normalize_strings = normalize_strings @abstractmethod def do_match(self, line: Line) -> TMatchResult: @@ -183,6 +196,7 @@ class CustomSplit: break_idx: int +@trait class CustomSplitMapMixin: """ This mixin class is used to map merged strings to a sequence of @@ -190,8 +204,10 @@ class CustomSplitMapMixin: the resultant substrings go over the configured max line length. """ - _Key = Tuple[StringID, str] - _CUSTOM_SPLIT_MAP: Dict[_Key, Tuple[CustomSplit, ...]] = defaultdict(tuple) + _Key: ClassVar = Tuple[StringID, str] + _CUSTOM_SPLIT_MAP: ClassVar[Dict[_Key, Tuple[CustomSplit, ...]]] = defaultdict( + tuple + ) @staticmethod def _get_key(string: str) -> "CustomSplitMapMixin._Key": @@ -242,7 +258,7 @@ class CustomSplitMapMixin: return key in self._CUSTOM_SPLIT_MAP -class StringMerger(CustomSplitMapMixin, StringTransformer): +class StringMerger(StringTransformer, CustomSplitMapMixin): """StringTransformer that merges strings together. Requirements: @@ -411,7 +427,7 @@ class StringMerger(CustomSplitMapMixin, StringTransformer): and is_valid_index(next_str_idx) and LL[next_str_idx].type == token.STRING ): - prefix = get_string_prefix(LL[next_str_idx].value) + prefix = get_string_prefix(LL[next_str_idx].value).lower() next_str_idx += 1 # The next loop merges the string group. The final string will be @@ -431,7 +447,7 @@ class StringMerger(CustomSplitMapMixin, StringTransformer): num_of_strings += 1 SS = LL[next_str_idx].value - next_prefix = get_string_prefix(SS) + next_prefix = get_string_prefix(SS).lower() # If this is an f-string group but this substring is not prefixed # with 'f'... @@ -541,7 +557,7 @@ class StringMerger(CustomSplitMapMixin, StringTransformer): return TErr("StringMerger does NOT merge multiline strings.") num_of_strings += 1 - prefix = get_string_prefix(leaf.value) + prefix = get_string_prefix(leaf.value).lower() if "r" in prefix: return TErr("StringMerger does NOT merge raw strings.") @@ -738,7 +754,7 @@ class BaseStringSplitter(StringTransformer): * The target string is not a multiline (i.e. triple-quote) string. """ - STRING_OPERATORS = [ + STRING_OPERATORS: Final = [ token.EQEQUAL, token.GREATER, token.GREATEREQUAL, @@ -926,7 +942,7 @@ class BaseStringSplitter(StringTransformer): return max_string_length -class StringSplitter(CustomSplitMapMixin, BaseStringSplitter): +class StringSplitter(BaseStringSplitter, CustomSplitMapMixin): """ StringTransformer that splits "atom" strings (i.e. strings which exist on lines by themselves). @@ -964,9 +980,9 @@ class StringSplitter(CustomSplitMapMixin, BaseStringSplitter): CustomSplit objects and add them to the custom split map. """ - MIN_SUBSTR_SIZE = 6 + MIN_SUBSTR_SIZE: Final = 6 # Matches an "f-expression" (e.g. {var}) that might be found in an f-string. - RE_FEXPR = r""" + RE_FEXPR: Final = r""" (? Iterator[Tuple[Index, Index]]: + """ + Yields: + All ranges of @string which, if @string were to be split there, + would result in the splitting of an \\N{...} expression (which is NOT + allowed). + """ + # True - the previous backslash was unescaped + # False - the previous backslash was escaped *or* there was no backslash + previous_was_unescaped_backslash = False + it = iter(enumerate(string)) + for idx, c in it: + if c == "\\": + previous_was_unescaped_backslash = not previous_was_unescaped_backslash + continue + if not previous_was_unescaped_backslash or c != "N": + previous_was_unescaped_backslash = False + continue + previous_was_unescaped_backslash = False + + begin = idx - 1 # the position of backslash before \N{...} + for idx, c in it: + if c == "}": + end = idx + break + else: + # malformed nameescape expression? + # should have been detected by AST parsing earlier... + raise RuntimeError(f"{self.__class__.__name__} LOGIC ERROR!") + yield begin, end + + def _iter_fexpr_slices(self, string: str) -> Iterator[Tuple[Index, Index]]: + """ + Yields: + All ranges of @string which, if @string were to be split there, + would result in the splitting of an f-expression (which is NOT + allowed). + """ + if "f" not in get_string_prefix(string).lower(): + return + + for match in re.finditer(self.RE_FEXPR, string, re.VERBOSE): + yield match.span() + + def _get_illegal_split_indices(self, string: str) -> Set[Index]: + illegal_indices: Set[Index] = set() + iterators = [ + self._iter_fexpr_slices(string), + self._iter_nameescape_slices(string), + ] + for it in iterators: + for begin, end in it: + illegal_indices.update(range(begin, end + 1)) + return illegal_indices + def _get_break_idx(self, string: str, max_break_idx: int) -> Optional[int]: """ This method contains the algorithm that StringSplitter uses to @@ -1272,40 +1343,15 @@ class StringSplitter(CustomSplitMapMixin, BaseStringSplitter): assert is_valid_index(max_break_idx) assert_is_leaf_string(string) - _fexpr_slices: Optional[List[Tuple[Index, Index]]] = None - - def fexpr_slices() -> Iterator[Tuple[Index, Index]]: - """ - Yields: - All ranges of @string which, if @string were to be split there, - would result in the splitting of an f-expression (which is NOT - allowed). - """ - nonlocal _fexpr_slices - - if _fexpr_slices is None: - _fexpr_slices = [] - for match in re.finditer(self.RE_FEXPR, string, re.VERBOSE): - _fexpr_slices.append(match.span()) - - yield from _fexpr_slices - - is_fstring = "f" in get_string_prefix(string) + _illegal_split_indices = self._get_illegal_split_indices(string) - def breaks_fstring_expression(i: Index) -> bool: + def breaks_unsplittable_expression(i: Index) -> bool: """ Returns: True iff returning @i would result in the splitting of an - f-expression (which is NOT allowed). + unsplittable expression (which is NOT allowed). """ - if not is_fstring: - return False - - for (start, end) in fexpr_slices(): - if start <= i < end: - return True - - return False + return i in _illegal_split_indices def passes_all_checks(i: Index) -> bool: """ @@ -1329,7 +1375,7 @@ class StringSplitter(CustomSplitMapMixin, BaseStringSplitter): is_space and is_not_escaped and is_big_enough - and not breaks_fstring_expression(i) + and not breaks_unsplittable_expression(i) ) # First, we check all indices BELOW @max_break_idx. @@ -1395,7 +1441,7 @@ class StringSplitter(CustomSplitMapMixin, BaseStringSplitter): return string_op_leaves -class StringParenWrapper(CustomSplitMapMixin, BaseStringSplitter): +class StringParenWrapper(BaseStringSplitter, CustomSplitMapMixin): """ StringTransformer that splits non-"atom" strings (i.e. strings that do not exist on lines by themselves). @@ -1780,20 +1826,20 @@ class StringParser: ``` """ - DEFAULT_TOKEN = -1 + DEFAULT_TOKEN: Final = 20210605 # String Parser States - START = 1 - DOT = 2 - NAME = 3 - PERCENT = 4 - SINGLE_FMT_ARG = 5 - LPAR = 6 - RPAR = 7 - DONE = 8 + START: Final = 1 + DOT: Final = 2 + NAME: Final = 3 + PERCENT: Final = 4 + SINGLE_FMT_ARG: Final = 5 + LPAR: Final = 6 + RPAR: Final = 7 + DONE: Final = 8 # Lookup Table for Next State - _goto: Dict[Tuple[ParserState, NodeType], ParserState] = { + _goto: Final[Dict[Tuple[ParserState, NodeType], ParserState]] = { # A string trailer may start with '.' OR '%'. (START, token.DOT): DOT, (START, token.PERCENT): PERCENT,