from abc import ABC, abstractmethod
from collections import defaultdict
from dataclasses import dataclass
-import regex as re
+import re
from typing import (
Any,
Callable,
+ ClassVar,
Collection,
Dict,
Iterable,
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
return Err(cant_transform)
-@dataclass # type: ignore
class StringTransformer(ABC):
"""
An implementation of the Transformer protocol that relies on its
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:
break_idx: int
+@trait
class CustomSplitMapMixin:
"""
This mixin class is used to map merged strings to a sequence of
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":
return key in self._CUSTOM_SPLIT_MAP
-class StringMerger(CustomSplitMapMixin, StringTransformer):
+class StringMerger(StringTransformer, CustomSplitMapMixin):
"""StringTransformer that merges strings together.
Requirements:
# 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)
* The target string is not a multiline (i.e. triple-quote) string.
"""
- STRING_OPERATORS = [
+ STRING_OPERATORS: Final = [
token.EQEQUAL,
token.GREATER,
token.GREATEREQUAL,
return max_string_length
-class StringSplitter(CustomSplitMapMixin, BaseStringSplitter):
+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):
"""
StringTransformer that splits "atom" strings (i.e. strings which exist on
lines by themselves).
CustomSplit objects and add them to the custom split map.
"""
- MIN_SUBSTR_SIZE = 6
- # Matches an "f-expression" (e.g. {var}) that might be found in an f-string.
- RE_FEXPR = r"""
- (?<!\{) (?:\{\{)* \{ (?!\{)
- (?:
- [^\{\}]
- | \{\{
- | \}\}
- | (?R)
- )+
- \}
- """
+ MIN_SUBSTR_SIZE: Final = 6
def do_splitter_match(self, line: Line) -> TMatchResult:
LL = line.leaves
# 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
"""
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()
"""
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) :]
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).
```
"""
- 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,
projects / etc / vim.git / blobdiff