cast,
TYPE_CHECKING,
)
-from typing_extensions import Final
from mypy_extensions import mypyc_attr
from appdirs import user_cache_dir
from _black_version import version as __version__
+if sys.version_info < (3, 8):
+ from typing_extensions import Final
+else:
+ from typing import Final
+
if TYPE_CHECKING:
import colorama # noqa: F401
DEFAULT_LINE_LENGTH = 88
-DEFAULT_EXCLUDES = r"/(\.eggs|\.git|\.hg|\.mypy_cache|\.nox|\.tox|\.venv|\.svn|_build|buck-out|build|dist)/" # noqa: B950
+DEFAULT_EXCLUDES = r"/(\.direnv|\.eggs|\.git|\.hg|\.mypy_cache|\.nox|\.tox|\.venv|\.svn|_build|buck-out|build|dist)/" # noqa: B950
DEFAULT_INCLUDES = r"\.pyi?$"
CACHE_DIR = Path(user_cache_dir("black", version=__version__))
+STDIN_PLACEHOLDER = "__BLACK_STDIN_FILENAME__"
STRING_PREFIX_CHARS: Final = "furbFURB" # All possible string prefix characters.
"""Raised when input source code fails all parse attempts."""
+class BracketMatchError(KeyError):
+ """Raised when an opening bracket is unable to be matched to a closing bracket."""
+
+
T = TypeVar("T")
E = TypeVar("E", bound=Exception)
PY36 = 6
PY37 = 7
PY38 = 8
+ PY39 = 9
def is_python2(self) -> bool:
return self is TargetVersion.PY27
-PY36_VERSIONS = {TargetVersion.PY36, TargetVersion.PY37, TargetVersion.PY38}
-
-
class Feature(Enum):
# All string literals are unicode
UNICODE_LITERALS = 1
ASYNC_KEYWORDS = 7
ASSIGNMENT_EXPRESSIONS = 8
POS_ONLY_ARGUMENTS = 9
+ RELAXED_DECORATORS = 10
+ FORCE_OPTIONAL_PARENTHESES = 50
VERSION_TO_FEATURES: Dict[TargetVersion, Set[Feature]] = {
Feature.ASSIGNMENT_EXPRESSIONS,
Feature.POS_ONLY_ARGUMENTS,
},
+ TargetVersion.PY39: {
+ Feature.UNICODE_LITERALS,
+ Feature.F_STRINGS,
+ Feature.NUMERIC_UNDERSCORES,
+ Feature.TRAILING_COMMA_IN_CALL,
+ Feature.TRAILING_COMMA_IN_DEF,
+ Feature.ASYNC_KEYWORDS,
+ Feature.ASSIGNMENT_EXPRESSIONS,
+ Feature.RELAXED_DECORATORS,
+ Feature.POS_ONLY_ARGUMENTS,
+ },
}
target_versions: Set[TargetVersion] = field(default_factory=set)
line_length: int = DEFAULT_LINE_LENGTH
string_normalization: bool = True
+ experimental_string_processing: bool = False
is_pyi: bool = False
def get_cache_key(self) -> str:
return all(feature in VERSION_TO_FEATURES[version] for version in target_versions)
-def find_pyproject_toml(path_search_start: str) -> Optional[str]:
+def find_pyproject_toml(path_search_start: Iterable[str]) -> Optional[str]:
"""Find the absolute filepath to a pyproject.toml if it exists"""
path_project_root = find_project_root(path_search_start)
path_pyproject_toml = path_project_root / "pyproject.toml"
"""
pyproject_toml = toml.load(path_config)
config = pyproject_toml.get("tool", {}).get("black", {})
- return {
- k.replace("--", "").replace("-", "_"): str(v)
- if not isinstance(v, (list, dict))
- else v
- for k, v in config.items()
- }
+ return {k.replace("--", "").replace("-", "_"): v for k, v in config.items()}
def read_pyproject_toml(
if not config:
return None
+ else:
+ # Sanitize the values to be Click friendly. For more information please see:
+ # https://github.com/psf/black/issues/1458
+ # https://github.com/pallets/click/issues/1567
+ config = {
+ k: str(v) if not isinstance(v, (list, dict)) else v
+ for k, v in config.items()
+ }
target_version = config.get("target_version")
if target_version is not None and not isinstance(target_version, list):
is_flag=True,
help="Don't normalize string quotes or prefixes.",
)
+@click.option(
+ "--experimental-string-processing",
+ is_flag=True,
+ hidden=True,
+ help=(
+ "Experimental option that performs more normalization on string literals."
+ " Currently disabled because it leads to some crashes."
+ ),
+)
@click.option(
"--check",
is_flag=True,
type=str,
help=(
"Like --exclude, but files and directories matching this regex will be "
- "excluded even when they are passed explicitly as arguments"
+ "excluded even when they are passed explicitly as arguments."
+ ),
+)
+@click.option(
+ "--stdin-filename",
+ type=str,
+ help=(
+ "The name of the file when passing it through stdin. Useful to make "
+ "sure Black will respect --force-exclude option on some "
+ "editors that rely on using stdin."
),
)
@click.option(
),
is_eager=True,
callback=read_pyproject_toml,
- help="Read configuration from PATH.",
+ help="Read configuration from FILE path.",
)
@click.pass_context
def main(
fast: bool,
pyi: bool,
skip_string_normalization: bool,
+ experimental_string_processing: bool,
quiet: bool,
verbose: bool,
include: str,
exclude: str,
force_exclude: Optional[str],
+ stdin_filename: Optional[str],
src: Tuple[str, ...],
config: Optional[str],
) -> None:
line_length=line_length,
is_pyi=pyi,
string_normalization=not skip_string_normalization,
+ experimental_string_processing=experimental_string_processing,
)
if config and verbose:
out(f"Using configuration from {config}.", bold=False, fg="blue")
exclude=exclude,
force_exclude=force_exclude,
report=report,
+ stdin_filename=stdin_filename,
)
path_empty(
exclude: str,
force_exclude: Optional[str],
report: "Report",
+ stdin_filename: Optional[str],
) -> Set[Path]:
"""Compute the set of files to be formatted."""
try:
root = find_project_root(src)
sources: Set[Path] = set()
path_empty(src, "No Path provided. Nothing to do 😴", quiet, verbose, ctx)
- exclude_regexes = [exclude_regex]
- if force_exclude_regex is not None:
- exclude_regexes.append(force_exclude_regex)
+ gitignore = get_gitignore(root)
for s in src:
- p = Path(s)
- if p.is_dir():
+ if s == "-" and stdin_filename:
+ p = Path(stdin_filename)
+ is_stdin = True
+ else:
+ p = Path(s)
+ is_stdin = False
+
+ if is_stdin or p.is_file():
+ normalized_path = normalize_path_maybe_ignore(p, root, report)
+ if normalized_path is None:
+ continue
+
+ normalized_path = "/" + normalized_path
+ # Hard-exclude any files that matches the `--force-exclude` regex.
+ if force_exclude_regex:
+ force_exclude_match = force_exclude_regex.search(normalized_path)
+ else:
+ force_exclude_match = None
+ if force_exclude_match and force_exclude_match.group(0):
+ report.path_ignored(p, "matches the --force-exclude regular expression")
+ continue
+
+ if is_stdin:
+ p = Path(f"{STDIN_PLACEHOLDER}{str(p)}")
+
+ sources.add(p)
+ elif p.is_dir():
sources.update(
gen_python_files(
p.iterdir(),
root,
include_regex,
- exclude_regexes,
+ exclude_regex,
+ force_exclude_regex,
report,
- get_gitignore(root),
+ gitignore,
)
)
elif s == "-":
sources.add(p)
- elif p.is_file():
- sources.update(
- gen_python_files(
- [p], root, None, exclude_regexes, report, get_gitignore(root)
- )
- )
else:
err(f"invalid path: {s}")
return sources
"""
Exit if there is no `src` provided for formatting
"""
- if len(src) == 0:
- if verbose or not quiet:
- out(msg)
- ctx.exit(0)
+ if not src and (verbose or not quiet):
+ out(msg)
+ ctx.exit(0)
def reformat_one(
"""
try:
changed = Changed.NO
- if not src.is_file() and str(src) == "-":
+
+ if str(src) == "-":
+ is_stdin = True
+ elif str(src).startswith(STDIN_PLACEHOLDER):
+ is_stdin = True
+ # Use the original name again in case we want to print something
+ # to the user
+ src = Path(str(src)[len(STDIN_PLACEHOLDER) :])
+ else:
+ is_stdin = False
+
+ if is_stdin:
if format_stdin_to_stdout(fast=fast, write_back=write_back, mode=mode):
changed = Changed.YES
else:
cache: Cache = {}
- if write_back != WriteBack.DIFF:
+ if write_back not in (WriteBack.DIFF, WriteBack.COLOR_DIFF):
cache = read_cache(mode)
res_src = src.resolve()
if res_src in cache and cache[res_src] == get_cache_info(res_src):
write_cache(cache, [src], mode)
report.done(src, changed)
except Exception as exc:
+ if report.verbose:
+ traceback.print_exc()
report.failed(src, str(exc))
worker_count = os.cpu_count()
if sys.platform == "win32":
# Work around https://bugs.python.org/issue26903
- worker_count = min(worker_count, 61)
+ worker_count = min(worker_count, 60)
try:
executor = ProcessPoolExecutor(max_workers=worker_count)
except (ImportError, OSError):
:func:`format_file_in_place`.
"""
cache: Cache = {}
- if write_back != WriteBack.DIFF:
+ if write_back not in (WriteBack.DIFF, WriteBack.COLOR_DIFF):
cache = read_cache(mode)
sources, cached = filter_cached(cache, sources)
for src in sorted(cached):
cancelled = []
sources_to_cache = []
lock = None
- if write_back == WriteBack.DIFF:
+ if write_back in (WriteBack.DIFF, WriteBack.COLOR_DIFF):
# For diff output, we need locks to ensure we don't interleave output
# from different processes.
manager = Manager()
for i, line in enumerate(lines):
if line.startswith("+++") or line.startswith("---"):
line = "\033[1;37m" + line + "\033[0m" # bold white, reset
- if line.startswith("@@"):
+ elif line.startswith("@@"):
line = "\033[36m" + line + "\033[0m" # cyan, reset
- if line.startswith("+"):
+ elif line.startswith("+"):
line = "\033[32m" + line + "\033[0m" # green, reset
elif line.startswith("-"):
line = "\033[31m" + line + "\033[0m" # red, reset
def wrap_stream_for_windows(
f: io.TextIOWrapper,
-) -> Union[io.TextIOWrapper, "colorama.AnsiToWin32.AnsiToWin32"]:
+) -> Union[io.TextIOWrapper, "colorama.AnsiToWin32"]:
"""
- Wrap the stream in colorama's wrap_stream so colors are shown on Windows.
+ Wrap stream with colorama's wrap_stream so colors are shown on Windows.
- If `colorama` is not found, then no change is made. If `colorama` does
- exist, then it handles the logic to determine whether or not to change
- things.
+ If `colorama` is unavailable, the original stream is returned unmodified.
+ Otherwise, the `wrap_stream()` function determines whether the stream needs
+ to be wrapped for a Windows environment and will accordingly either return
+ an `AnsiToWin32` wrapper or the original stream.
"""
try:
- from colorama import initialise
-
- # We set `strip=False` so that we can don't have to modify
- # test_express_diff_with_color.
- f = initialise.wrap_stream(
- f, convert=None, strip=False, autoreset=False, wrap=True
- )
-
- # wrap_stream returns a `colorama.AnsiToWin32.AnsiToWin32` object
- # which does not have a `detach()` method. So we fake one.
- f.detach = lambda *args, **kwargs: None # type: ignore
+ from colorama.initialise import wrap_stream
except ImportError:
- pass
-
- return f
+ return f
+ else:
+ # Set `strip=False` to avoid needing to modify test_express_diff_with_color.
+ return wrap_stream(f, convert=None, strip=False, autoreset=False, wrap=True)
def format_stdin_to_stdout(
def format_file_contents(src_contents: str, *, fast: bool, mode: Mode) -> FileContent:
- """Reformat contents a file and return new contents.
+ """Reformat contents of a file and return new contents.
If `fast` is False, additionally confirm that the reformatted code is
valid by calling :func:`assert_equivalent` and :func:`assert_stable` on it.
`mode` is passed to :func:`format_str`.
"""
- if src_contents.strip() == "":
+ if not src_contents.strip():
raise NothingChanged
dst_contents = format_str(src_contents, mode=mode)
allowed. Example:
>>> import black
- >>> print(black.format_str("def f(arg:str='')->None:...", mode=Mode()))
+ >>> print(black.format_str("def f(arg:str='')->None:...", mode=black.Mode()))
def f(arg: str = "") -> None:
...
A more complex example:
+
>>> print(
... black.format_str(
... "def f(arg:str='')->None: hey",
before, after = elt.maybe_empty_lines(current_line)
dst_contents.append(str(empty_line) * before)
for line in transform_line(
- current_line,
- line_length=mode.line_length,
- normalize_strings=mode.string_normalization,
- features=split_line_features,
+ current_line, mode=mode, features=split_line_features
):
dst_contents.append(str(line))
return "".join(dst_contents)
def lib2to3_parse(src_txt: str, target_versions: Iterable[TargetVersion] = ()) -> Node:
"""Given a string with source, return the lib2to3 Node."""
- if src_txt[-1:] != "\n":
+ if not src_txt.endswith("\n"):
src_txt += "\n"
for grammar in get_grammars(set(target_versions)):
previous: Optional[Leaf] = None
_for_loop_depths: List[int] = field(default_factory=list)
_lambda_argument_depths: List[int] = field(default_factory=list)
+ invisible: List[Leaf] = field(default_factory=list)
def mark(self, leaf: Leaf) -> None:
"""Mark `leaf` with bracket-related metadata. Keep track of delimiters.
self.maybe_decrement_after_lambda_arguments(leaf)
if leaf.type in CLOSING_BRACKETS:
self.depth -= 1
- opening_bracket = self.bracket_match.pop((self.depth, leaf.type))
+ try:
+ opening_bracket = self.bracket_match.pop((self.depth, leaf.type))
+ except KeyError as e:
+ raise BracketMatchError(
+ "Unable to match a closing bracket to the following opening"
+ f" bracket: {leaf}"
+ ) from e
leaf.opening_bracket = opening_bracket
+ if not leaf.value:
+ self.invisible.append(leaf)
leaf.bracket_depth = self.depth
if self.depth == 0:
delim = is_split_before_delimiter(leaf, self.previous)
if leaf.type in OPENING_BRACKETS:
self.bracket_match[self.depth, BRACKET[leaf.type]] = leaf
self.depth += 1
+ if not leaf.value:
+ self.invisible.append(leaf)
self.previous = leaf
self.maybe_increment_lambda_arguments(leaf)
self.maybe_increment_for_loop_variable(leaf)
)
if self.inside_brackets or not preformatted:
self.bracket_tracker.mark(leaf)
- self.maybe_remove_trailing_comma(leaf)
+ if self.maybe_should_explode(leaf):
+ self.should_explode = True
if not self.append_comment(leaf):
self.leaves.append(leaf)
Leaf(token.DOT, ".") for _ in range(3)
]
- @property
- def is_collection_with_optional_trailing_comma(self) -> bool:
- """Is this line a collection literal with a trailing comma that's optional?
-
- Note that the trailing comma in a 1-tuple is not optional.
- """
- if not self.leaves or len(self.leaves) < 4:
- return False
-
- # Look for and address a trailing colon.
- if self.leaves[-1].type == token.COLON:
- closer = self.leaves[-2]
- close_index = -2
- else:
- closer = self.leaves[-1]
- close_index = -1
- if closer.type not in CLOSING_BRACKETS or self.inside_brackets:
- return False
-
- if closer.type == token.RPAR:
- # Tuples require an extra check, because if there's only
- # one element in the tuple removing the comma unmakes the
- # tuple.
- #
- # We also check for parens before looking for the trailing
- # comma because in some cases (eg assigning a dict
- # literal) the literal gets wrapped in temporary parens
- # during parsing. This case is covered by the
- # collections.py test data.
- opener = closer.opening_bracket
- for _open_index, leaf in enumerate(self.leaves):
- if leaf is opener:
- break
-
- else:
- # Couldn't find the matching opening paren, play it safe.
- return False
-
- commas = 0
- comma_depth = self.leaves[close_index - 1].bracket_depth
- for leaf in self.leaves[_open_index + 1 : close_index]:
- if leaf.bracket_depth == comma_depth and leaf.type == token.COMMA:
- commas += 1
- if commas > 1:
- # We haven't looked yet for the trailing comma because
- # we might also have caught noop parens.
- return self.leaves[close_index - 1].type == token.COMMA
-
- elif commas == 1:
- return False # it's either a one-tuple or didn't have a trailing comma
-
- if self.leaves[close_index - 1].type in CLOSING_BRACKETS:
- close_index -= 1
- closer = self.leaves[close_index]
- if closer.type == token.RPAR:
- # TODO: this is a gut feeling. Will we ever see this?
- return False
-
- if self.leaves[close_index - 1].type != token.COMMA:
- return False
-
- return True
-
@property
def is_def(self) -> bool:
"""Is this a function definition? (Also returns True for async defs.)"""
def contains_multiline_strings(self) -> bool:
return any(is_multiline_string(leaf) for leaf in self.leaves)
- def maybe_remove_trailing_comma(self, closing: Leaf) -> bool:
- """Remove trailing comma if there is one and it's safe."""
- if not (self.leaves and self.leaves[-1].type == token.COMMA):
- return False
-
- # We remove trailing commas only in the case of importing a
- # single name from a module.
+ def maybe_should_explode(self, closing: Leaf) -> bool:
+ """Return True if this line should explode (always be split), that is when:
+ - there's a trailing comma here; and
+ - it's not a one-tuple.
+ """
if not (
- self.leaves
- and self.is_import
- and len(self.leaves) > 4
+ closing.type in CLOSING_BRACKETS
+ and self.leaves
and self.leaves[-1].type == token.COMMA
- and closing.type in CLOSING_BRACKETS
- and self.leaves[-4].type == token.NAME
- and (
- # regular `from foo import bar,`
- self.leaves[-4].value == "import"
- # `from foo import (bar as baz,)
- or (
- len(self.leaves) > 6
- and self.leaves[-6].value == "import"
- and self.leaves[-3].value == "as"
- )
- # `from foo import bar as baz,`
- or (
- len(self.leaves) > 5
- and self.leaves[-5].value == "import"
- and self.leaves[-3].value == "as"
- )
- )
- and closing.type == token.RPAR
):
return False
- self.remove_trailing_comma()
- return True
+ if closing.type in {token.RBRACE, token.RSQB}:
+ return True
+
+ if self.is_import:
+ return True
+
+ if not is_one_tuple_between(closing.opening_bracket, closing, self.leaves):
+ return True
+
+ return False
def append_comment(self, comment: Leaf) -> bool:
"""Add an inline or standalone comment to the line."""
return 0, 0
if self.previous_line.is_decorator:
+ if self.is_pyi and current_line.is_stub_class:
+ # Insert an empty line after a decorated stub class
+ return 0, 1
+
return 0, 0
if self.previous_line.depth < current_line.depth and (
newlines = 0
else:
newlines = 1
- elif current_line.is_def and not self.previous_line.is_def:
- # Blank line between a block of functions and a block of non-functions
+ elif (
+ current_line.is_def or current_line.is_decorator
+ ) and not self.previous_line.is_def:
+ # Blank line between a block of functions (maybe with preceding
+ # decorators) and a block of non-functions
newlines = 1
else:
newlines = 0
yield from self.visit_default(node)
def visit_STRING(self, leaf: Leaf) -> Iterator[Line]:
- # Check if it's a docstring
- if prev_siblings_are(
- leaf.parent, [None, token.NEWLINE, token.INDENT, syms.simple_stmt]
- ) and is_multiline_string(leaf):
- prefix = " " * self.current_line.depth
- docstring = fix_docstring(leaf.value[3:-3], prefix)
- leaf.value = leaf.value[0:3] + docstring + leaf.value[-3:]
- normalize_string_quotes(leaf)
+ 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)
+ lead_len = len(prefix) + 3
+ tail_len = -3
+ indent = " " * 4 * self.current_line.depth
+ docstring = fix_docstring(leaf.value[lead_len:tail_len], indent)
+ if docstring:
+ if leaf.value[lead_len - 1] == docstring[0]:
+ docstring = " " + docstring
+ if leaf.value[tail_len + 1] == docstring[-1]:
+ docstring = docstring + " "
+ leaf.value = leaf.value[0:lead_len] + docstring + leaf.value[tail_len:]
yield from self.visit_default(leaf)
):
# Python 2 print chevron
return NO
+ elif prevp.type == token.AT and p.parent and p.parent.type == syms.decorator:
+ # no space in decorators
+ return NO
elif prev.type in OPENING_BRACKETS:
return NO
def transform_line(
- line: Line,
- line_length: int,
- normalize_strings: bool,
- features: Collection[Feature] = (),
+ line: Line, mode: Mode, features: Collection[Feature] = ()
) -> Iterator[Line]:
"""Transform a `line`, potentially splitting it into many lines.
def init_st(ST: Type[StringTransformer]) -> StringTransformer:
"""Initialize StringTransformer"""
- return ST(line_length, normalize_strings)
+ return ST(mode.line_length, mode.string_normalization)
string_merge = init_st(StringMerger)
string_paren_strip = init_st(StringParenStripper)
if (
not line.contains_uncollapsable_type_comments()
and not line.should_explode
- and not line.is_collection_with_optional_trailing_comma
and (
- is_line_short_enough(line, line_length=line_length, line_str=line_str)
+ is_line_short_enough(line, line_length=mode.line_length, line_str=line_str)
or line.contains_unsplittable_type_ignore()
)
- and not (line.contains_standalone_comments() and line.inside_brackets)
+ and not (line.inside_brackets and line.contains_standalone_comments())
):
# Only apply basic string preprocessing, since lines shouldn't be split here.
- transformers = [string_merge, string_paren_strip]
+ if mode.experimental_string_processing:
+ transformers = [string_merge, string_paren_strip]
+ else:
+ transformers = []
elif line.is_def:
transformers = [left_hand_split]
else:
def rhs(line: Line, features: Collection[Feature]) -> Iterator[Line]:
- for omit in generate_trailers_to_omit(line, line_length):
- lines = list(right_hand_split(line, line_length, features, omit=omit))
- if is_line_short_enough(lines[0], line_length=line_length):
+ """Wraps calls to `right_hand_split`.
+
+ The calls increasingly `omit` right-hand trailers (bracket pairs with
+ content), meaning the trailers get glued together to split on another
+ bracket pair instead.
+ """
+ for omit in generate_trailers_to_omit(line, mode.line_length):
+ lines = list(
+ right_hand_split(line, mode.line_length, features, omit=omit)
+ )
+ # Note: this check is only able to figure out if the first line of the
+ # *current* transformation fits in the line length. This is true only
+ # for simple cases. All others require running more transforms via
+ # `transform_line()`. This check doesn't know if those would succeed.
+ if is_line_short_enough(lines[0], line_length=mode.line_length):
yield from lines
return
# All splits failed, best effort split with no omits.
# This mostly happens to multiline strings that are by definition
- # reported as not fitting a single line.
- # line_length=1 here was historically a bug that somehow became a feature.
- # See #762 and #781 for the full story.
- yield from right_hand_split(line, line_length=1, features=features)
-
- if line.inside_brackets:
- transformers = [
- string_merge,
- string_paren_strip,
- delimiter_split,
- standalone_comment_split,
- string_split,
- string_paren_wrap,
- rhs,
- ]
+ # reported as not fitting a single line, as well as lines that contain
+ # trailing commas (those have to be exploded).
+ yield from right_hand_split(
+ line, line_length=mode.line_length, features=features
+ )
+
+ if mode.experimental_string_processing:
+ if line.inside_brackets:
+ transformers = [
+ string_merge,
+ string_paren_strip,
+ string_split,
+ delimiter_split,
+ standalone_comment_split,
+ string_paren_wrap,
+ rhs,
+ ]
+ else:
+ transformers = [
+ string_merge,
+ string_paren_strip,
+ string_split,
+ string_paren_wrap,
+ rhs,
+ ]
else:
- transformers = [
- string_merge,
- string_paren_strip,
- string_split,
- string_paren_wrap,
- rhs,
- ]
+ if line.inside_brackets:
+ transformers = [delimiter_split, standalone_comment_split, rhs]
+ else:
+ transformers = [rhs]
for transform in transformers:
# We are accumulating lines in `result` because we might want to abort
# mission and return the original line in the end, or attempt a different
# split altogether.
- result: List[Line] = []
try:
- for transformed_line in transform(line, features):
- if str(transformed_line).strip("\n") == line_str:
- raise CannotTransform(
- "Line transformer returned an unchanged result"
- )
-
- result.extend(
- transform_line(
- transformed_line,
- line_length=line_length,
- normalize_strings=normalize_strings,
- features=features,
- )
- )
+ result = run_transformer(line, transform, mode, features, line_str=line_str)
except CannotTransform:
continue
else:
line_length: int
normalize_strings: bool
+ __name__ = "StringTransformer"
@abstractmethod
def do_match(self, line: Line) -> TMatchResult:
"""StringTransformer that merges strings together.
Requirements:
- (A) The line contains adjacent strings such that at most one substring
- has inline comments AND none of those inline comments are pragmas AND
- the set of all substring prefixes is either of length 1 or equal to
- {"", "f"} AND none of the substrings are raw strings (i.e. are prefixed
- with 'r').
+ (A) The line contains adjacent strings such that ALL of the validation checks
+ listed in StringMerger.__validate_msg(...)'s docstring pass.
OR
(B) The line contains a string which uses line continuation backslashes.
)
new_line = line.clone()
- new_line.comments = line.comments
+ new_line.comments = line.comments.copy()
append_leaves(new_line, line, LL)
new_string_leaf = new_line.leaves[string_idx]
* Ok(None), if ALL validation checks (listed below) pass.
OR
* Err(CannotTransform), if any of the following are true:
+ - The target string group does not contain ANY stand-alone comments.
- The target string is not in a string group (i.e. it has no
adjacent strings).
- The string group has more than one inline comment.
length greater than one and is not equal to {"", "f"}.
- The string group consists of raw strings.
"""
+ # We first check for "inner" stand-alone comments (i.e. stand-alone
+ # comments that have a string leaf before them AND after them).
+ for inc in [1, -1]:
+ i = string_idx
+ found_sa_comment = False
+ is_valid_index = is_valid_index_factory(line.leaves)
+ while is_valid_index(i) and line.leaves[i].type in [
+ token.STRING,
+ STANDALONE_COMMENT,
+ ]:
+ if line.leaves[i].type == STANDALONE_COMMENT:
+ found_sa_comment = True
+ elif found_sa_comment:
+ return TErr(
+ "StringMerger does NOT merge string groups which contain "
+ "stand-alone comments."
+ )
+
+ i += inc
+
num_of_inline_string_comments = 0
set_of_prefixes = set()
num_of_strings = 0
Requirements:
The line contains a string which is surrounded by parentheses and:
- - The target string is NOT the only argument to a function call).
- - The RPAR is NOT followed by an attribute access (i.e. a dot).
+ - The target string is NOT the only argument to a function call.
+ - The target string is NOT a "pointless" string.
+ - If the target string contains a PERCENT, the brackets are not
+ preceeded or followed by an operator with higher precedence than
+ PERCENT.
Transformations:
The parentheses mentioned in the 'Requirements' section are stripped.
if leaf.type != token.STRING:
continue
+ # If this is a "pointless" string...
+ if (
+ leaf.parent
+ and leaf.parent.parent
+ and leaf.parent.parent.type == syms.simple_stmt
+ ):
+ continue
+
# Should be preceded by a non-empty LPAR...
if (
not is_valid_index(idx - 1)
string_parser = StringParser()
next_idx = string_parser.parse(LL, string_idx)
+ # if the leaves in the parsed string include a PERCENT, we need to
+ # make sure the initial LPAR is NOT preceded by an operator with
+ # higher or equal precedence to PERCENT
+ if is_valid_index(idx - 2):
+ # mypy can't quite follow unless we name this
+ before_lpar = LL[idx - 2]
+ if token.PERCENT in {leaf.type for leaf in LL[idx - 1 : next_idx]} and (
+ (
+ before_lpar.type
+ in {
+ token.STAR,
+ token.AT,
+ token.SLASH,
+ token.DOUBLESLASH,
+ token.PERCENT,
+ token.TILDE,
+ token.DOUBLESTAR,
+ token.AWAIT,
+ token.LSQB,
+ token.LPAR,
+ }
+ )
+ or (
+ # only unary PLUS/MINUS
+ before_lpar.parent
+ and before_lpar.parent.type == syms.factor
+ and (before_lpar.type in {token.PLUS, token.MINUS})
+ )
+ ):
+ continue
+
# Should be followed by a non-empty RPAR...
if (
is_valid_index(next_idx)
and LL[next_idx].type == token.RPAR
and not is_empty_rpar(LL[next_idx])
):
- # That RPAR should NOT be followed by a '.' symbol.
- if is_valid_index(next_idx + 1) and LL[next_idx + 1].type == token.DOT:
+ # That RPAR should NOT be followed by anything with higher
+ # precedence than PERCENT
+ if is_valid_index(next_idx + 1) and LL[next_idx + 1].type in {
+ token.DOUBLESTAR,
+ token.LSQB,
+ token.LPAR,
+ token.DOT,
+ }:
continue
return Ok(string_idx)
yield TErr(
"Will not strip parentheses which have comments attached to them."
)
+ return
new_line = line.clone()
new_line.comments = line.comments.copy()
-
- append_leaves(new_line, line, LL[: string_idx - 1])
+ 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)
string_leaf = Leaf(token.STRING, LL[string_idx].value)
LL[string_idx - 1].remove()
new_line.append(string_leaf)
append_leaves(
- new_line, line, LL[string_idx + 1 : rpar_idx] + LL[rpar_idx + 1 :],
+ new_line, line, LL[string_idx + 1 : rpar_idx] + LL[rpar_idx + 1 :]
)
LL[rpar_idx].remove()
# WMA4 a single space.
offset += 1
- # WMA4 the lengths of any leaves that came before that space.
- for leaf in LL[: p_idx + 1]:
+ # WMA4 the lengths of any leaves that came before that space,
+ # but after any closing bracket before that space.
+ for leaf in reversed(LL[: p_idx + 1]):
offset += len(str(leaf))
+ if leaf.type in CLOSING_BRACKETS:
+ break
if is_valid_index(string_idx + 1):
N = LL[string_idx + 1]
MIN_SUBSTR_SIZE characters.
The string will ONLY be split on spaces (i.e. each new substring should
- start with a space).
+ start with a space). Note that the string will NOT be split on a space
+ which is escaped with a backslash.
If the string is an f-string, it will NOT be split in the middle of an
f-expression (e.g. in f"FooBar: {foo() if x else bar()}", {foo() if x
MIN_SUBSTR_SIZE = 6
# Matches an "f-expression" (e.g. {var}) that might be found in an f-string.
RE_FEXPR = r"""
- (?<!\{)\{
+ (?<!\{) (?:\{\{)* \{ (?!\{)
(?:
[^\{\}]
| \{\{
| \}\}
+ | (?R)
)+?
- (?<!\})(?:\}\})*\}(?!\})
+ (?<!\}) \} (?:\}\})* (?!\})
"""
def do_splitter_match(self, line: Line) -> TMatchResult:
section of this classes' docstring would be be met by returning @i.
"""
is_space = string[i] == " "
+
+ is_not_escaped = True
+ j = i - 1
+ while is_valid_index(j) and string[j] == "\\":
+ is_not_escaped = not is_not_escaped
+ j -= 1
+
is_big_enough = (
len(string[i:]) >= self.MIN_SUBSTR_SIZE
and len(string[:i]) >= self.MIN_SUBSTR_SIZE
)
- return is_space and is_big_enough and not breaks_fstring_expression(i)
+ return (
+ is_space
+ and is_not_escaped
+ and is_big_enough
+ and not breaks_fstring_expression(i)
+ )
# First, we check all indices BELOW @max_break_idx.
break_idx = max_break_idx
def do_splitter_match(self, line: Line) -> TMatchResult:
LL = line.leaves
- string_idx = None
- string_idx = string_idx or self._return_match(LL)
- string_idx = string_idx or self._else_match(LL)
- string_idx = string_idx or self._assert_match(LL)
- string_idx = string_idx or self._assign_match(LL)
- string_idx = string_idx or self._dict_match(LL)
+ string_idx = (
+ self._return_match(LL)
+ or self._else_match(LL)
+ or self._assert_match(LL)
+ or self._assign_match(LL)
+ or self._dict_match(LL)
+ )
if string_idx is not None:
string_value = line.leaves[string_idx].value
is_valid_index = is_valid_index_factory(LL)
insert_str_child = insert_str_child_factory(LL[string_idx])
- comma_idx = len(LL) - 1
+ comma_idx = -1
ends_with_comma = False
if LL[comma_idx].type == token.COMMA:
ends_with_comma = True
return str(line).strip("\n")
-def append_leaves(new_line: Line, old_line: Line, leaves: List[Leaf]) -> None:
+def append_leaves(
+ new_line: Line, old_line: Line, leaves: List[Leaf], preformatted: bool = False
+) -> None:
"""
Append leaves (taken from @old_line) to @new_line, making sure to fix the
underlying Node structure where appropriate.
set(@leaves) is a subset of set(@old_line.leaves).
"""
for old_leaf in leaves:
- assert old_leaf in old_line.leaves
-
new_leaf = Leaf(old_leaf.type, old_leaf.value)
replace_child(old_leaf, new_leaf)
- new_line.append(new_leaf)
+ new_line.append(new_leaf, preformatted=preformatted)
for comment_leaf in old_line.comments_after(old_leaf):
new_line.append(comment_leaf, preformatted=True)
tail = bracket_split_build_line(tail_leaves, line, opening_bracket)
bracket_split_succeeded_or_raise(head, body, tail)
if (
- # the body shouldn't be exploded
- not body.should_explode
+ Feature.FORCE_OPTIONAL_PARENTHESES not in features
# the opening bracket is an optional paren
and opening_bracket.type == token.LPAR
and not opening_bracket.value
# there are no standalone comments in the body
and not body.contains_standalone_comments(0)
# and we can actually remove the parens
- and can_omit_invisible_parens(body, line_length)
+ and can_omit_invisible_parens(body, line_length, omit_on_explode=omit)
):
omit = {id(closing_bracket), *omit}
try:
continue
if leaves[i].type != token.COMMA:
- leaves.insert(i + 1, Leaf(token.COMMA, ","))
+ new_comma = Leaf(token.COMMA, ",")
+ leaves.insert(i + 1, new_comma)
break
# Populate the line
result.append(leaf, preformatted=True)
for comment_after in original.comments_after(leaf):
result.append(comment_after, preformatted=True)
- if is_body:
- result.should_explode = should_explode(result, opening_bracket)
+ if is_body and should_split_body_explode(result, opening_bracket):
+ result.should_explode = True
return result
and current_line.leaves[-1].type != token.COMMA
and current_line.leaves[-1].type != STANDALONE_COMMENT
):
- current_line.append(Leaf(token.COMMA, ","))
+ new_comma = Leaf(token.COMMA, ",")
+ current_line.append(new_comma)
yield current_line
# Leave octal and binary literals alone.
pass
elif text.startswith("0x"):
- # Change hex literals to upper case.
- before, after = text[:2], text[2:]
- text = f"{before}{after.upper()}"
+ text = format_hex(text)
elif "e" in text:
- before, after = text.split("e")
- sign = ""
- if after.startswith("-"):
- after = after[1:]
- sign = "-"
- elif after.startswith("+"):
- after = after[1:]
- before = format_float_or_int_string(before)
- text = f"{before}e{sign}{after}"
+ text = format_scientific_notation(text)
elif text.endswith(("j", "l")):
- number = text[:-1]
- suffix = text[-1]
- # Capitalize in "2L" because "l" looks too similar to "1".
- if suffix == "l":
- suffix = "L"
- text = f"{format_float_or_int_string(number)}{suffix}"
+ text = format_long_or_complex_number(text)
else:
text = format_float_or_int_string(text)
leaf.value = text
+def format_hex(text: str) -> str:
+ """
+ Formats a hexadecimal string like "0x12b3"
+
+ Uses lowercase because of similarity between "B" and "8", which
+ can cause security issues.
+ see: https://github.com/psf/black/issues/1692
+ """
+
+ before, after = text[:2], text[2:]
+ return f"{before}{after.lower()}"
+
+
+def format_scientific_notation(text: str) -> str:
+ """Formats a numeric string utilizing scentific notation"""
+ before, after = text.split("e")
+ sign = ""
+ if after.startswith("-"):
+ after = after[1:]
+ sign = "-"
+ elif after.startswith("+"):
+ after = after[1:]
+ before = format_float_or_int_string(before)
+ return f"{before}e{sign}{after}"
+
+
+def format_long_or_complex_number(text: str) -> str:
+ """Formats a long or complex string like `10L` or `10j`"""
+ number = text[:-1]
+ suffix = text[-1]
+ # Capitalize in "2L" because "l" looks too similar to "1".
+ if suffix == "l":
+ suffix = "L"
+ return f"{format_float_or_int_string(number)}{suffix}"
+
+
def format_float_or_int_string(text: str) -> str:
"""Formats a float string like "1.0"."""
if "." not in text:
if check_lpar:
if is_walrus_assignment(child):
- continue
+ pass
- if child.type == syms.atom:
+ elif child.type == syms.atom:
if maybe_make_parens_invisible_in_atom(child, parent=node):
wrap_in_parentheses(node, child, visible=False)
elif is_one_tuple(child):
return inner is not None and inner.type == syms.namedexpr_test
+def is_simple_decorator_trailer(node: LN, last: bool = False) -> bool:
+ """Return True iff `node` is a trailer valid in a simple decorator"""
+ return node.type == syms.trailer and (
+ (
+ len(node.children) == 2
+ and node.children[0].type == token.DOT
+ and node.children[1].type == token.NAME
+ )
+ # last trailer can be arguments
+ or (
+ last
+ and len(node.children) == 3
+ and node.children[0].type == token.LPAR
+ # and node.children[1].type == syms.argument
+ and node.children[2].type == token.RPAR
+ )
+ )
+
+
+def is_simple_decorator_expression(node: LN) -> bool:
+ """Return True iff `node` could be a 'dotted name' decorator
+
+ This function takes the node of the 'namedexpr_test' of the new decorator
+ grammar and test if it would be valid under the old decorator grammar.
+
+ The old grammar was: decorator: @ dotted_name [arguments] NEWLINE
+ The new grammar is : decorator: @ namedexpr_test NEWLINE
+ """
+ if node.type == token.NAME:
+ return True
+ if node.type == syms.power:
+ if node.children:
+ return (
+ node.children[0].type == token.NAME
+ and all(map(is_simple_decorator_trailer, node.children[1:-1]))
+ and (
+ len(node.children) < 2
+ or is_simple_decorator_trailer(node.children[-1], last=True)
+ )
+ )
+ return False
+
+
def is_yield(node: LN) -> bool:
"""Return True if `node` holds a `yield` or `yield from` expression."""
if node.type == syms.yield_expr:
leaf.value = ")"
-def should_explode(line: Line, opening_bracket: Leaf) -> bool:
- """Should `line` immediately be split with `delimiter_split()` after RHS?"""
+def should_split_body_explode(line: Line, opening_bracket: Leaf) -> bool:
+ """Should `line` be immediately split with `delimiter_split()` after RHS?"""
- if not (
- opening_bracket.parent
- and opening_bracket.parent.type in {syms.atom, syms.import_from}
- and opening_bracket.value in "[{("
- ):
+ if not (opening_bracket.parent and opening_bracket.value in "[{("):
return False
+ # We're essentially checking if the body is delimited by commas and there's more
+ # than one of them (we're excluding the trailing comma and if the delimiter priority
+ # is still commas, that means there's more).
+ exclude = set()
+ trailing_comma = False
try:
last_leaf = line.leaves[-1]
- exclude = {id(last_leaf)} if last_leaf.type == token.COMMA else set()
+ if last_leaf.type == token.COMMA:
+ trailing_comma = True
+ exclude.add(id(last_leaf))
max_priority = line.bracket_tracker.max_delimiter_priority(exclude=exclude)
except (IndexError, ValueError):
return False
- return max_priority == COMMA_PRIORITY
+ return max_priority == COMMA_PRIORITY and (
+ trailing_comma
+ # always explode imports
+ or opening_bracket.parent.type in {syms.atom, syms.import_from}
+ )
+
+
+def is_one_tuple_between(opening: Leaf, closing: Leaf, leaves: List[Leaf]) -> bool:
+ """Return True if content between `opening` and `closing` looks like a one-tuple."""
+ if opening.type != token.LPAR and closing.type != token.RPAR:
+ return False
+
+ depth = closing.bracket_depth + 1
+ for _opening_index, leaf in enumerate(leaves):
+ if leaf is opening:
+ break
+
+ else:
+ raise LookupError("Opening paren not found in `leaves`")
+
+ commas = 0
+ _opening_index += 1
+ for leaf in leaves[_opening_index:]:
+ if leaf is closing:
+ break
+
+ bracket_depth = leaf.bracket_depth
+ if bracket_depth == depth and leaf.type == token.COMMA:
+ commas += 1
+ if leaf.parent and leaf.parent.type in {
+ syms.arglist,
+ syms.typedargslist,
+ }:
+ commas += 1
+ break
+
+ return commas < 2
def get_features_used(node: Node) -> Set[Feature]:
- underscores in numeric literals;
- trailing commas after * or ** in function signatures and calls;
- positional only arguments in function signatures and lambdas;
+ - assignment expression;
+ - relaxed decorator syntax;
"""
features: Set[Feature] = set()
for n in node.pre_order():
elif n.type == token.COLONEQUAL:
features.add(Feature.ASSIGNMENT_EXPRESSIONS)
+ elif n.type == syms.decorator:
+ if len(n.children) > 1 and not is_simple_decorator_expression(
+ n.children[1]
+ ):
+ features.add(Feature.RELAXED_DECORATORS)
+
elif (
n.type in {syms.typedargslist, syms.arglist}
and n.children
a preceding closing bracket fits in one line.
Yielded sets are cumulative (contain results of previous yields, too). First
- set is empty.
+ set is empty, unless the line should explode, in which case bracket pairs until
+ the one that needs to explode are omitted.
"""
omit: Set[LeafID] = set()
- yield omit
+ if not line.should_explode:
+ yield omit
length = 4 * line.depth
opening_bracket: Optional[Leaf] = None
if leaf is opening_bracket:
opening_bracket = None
elif leaf.type in CLOSING_BRACKETS:
+ prev = line.leaves[index - 1] if index > 0 else None
+ if (
+ line.should_explode
+ and prev
+ and prev.type == token.COMMA
+ and not is_one_tuple_between(
+ leaf.opening_bracket, leaf, line.leaves
+ )
+ ):
+ # Never omit bracket pairs with trailing commas.
+ # We need to explode on those.
+ break
+
inner_brackets.add(id(leaf))
elif leaf.type in CLOSING_BRACKETS:
- if index > 0 and line.leaves[index - 1].type in OPENING_BRACKETS:
+ prev = line.leaves[index - 1] if index > 0 else None
+ if prev and prev.type in OPENING_BRACKETS:
# Empty brackets would fail a split so treat them as "inner"
# brackets (e.g. only add them to the `omit` set if another
# pair of brackets was good enough.
inner_brackets.clear()
yield omit
+ if (
+ line.should_explode
+ and prev
+ and prev.type == token.COMMA
+ and not is_one_tuple_between(leaf.opening_bracket, leaf, line.leaves)
+ ):
+ # Never omit bracket pairs with trailing commas.
+ # We need to explode on those.
+ break
+
if leaf.value:
opening_bracket = leaf.opening_bracket
closing_bracket = leaf
return PathSpec.from_lines("gitwildmatch", lines)
+def normalize_path_maybe_ignore(
+ path: Path, root: Path, report: "Report"
+) -> Optional[str]:
+ """Normalize `path`. May return `None` if `path` was ignored.
+
+ `report` is where "path ignored" output goes.
+ """
+ try:
+ abspath = path if path.is_absolute() else Path.cwd() / path
+ normalized_path = abspath.resolve().relative_to(root).as_posix()
+ except OSError as e:
+ report.path_ignored(path, f"cannot be read because {e}")
+ return None
+
+ except ValueError:
+ if path.is_symlink():
+ report.path_ignored(path, f"is a symbolic link that points outside {root}")
+ return None
+
+ raise
+
+ return normalized_path
+
+
def gen_python_files(
paths: Iterable[Path],
root: Path,
include: Optional[Pattern[str]],
- exclude_regexes: Iterable[Pattern[str]],
+ exclude: Pattern[str],
+ force_exclude: Optional[Pattern[str]],
report: "Report",
gitignore: PathSpec,
) -> Iterator[Path]:
"""Generate all files under `path` whose paths are not excluded by the
- `exclude` regex, but are included by the `include` regex.
+ `exclude_regex` or `force_exclude` regexes, but are included by the `include` regex.
Symbolic links pointing outside of the `root` directory are ignored.
"""
assert root.is_absolute(), f"INTERNAL ERROR: `root` must be absolute but is {root}"
for child in paths:
- # Then ignore with `exclude` option.
- try:
- normalized_path = child.resolve().relative_to(root).as_posix()
- except OSError as e:
- report.path_ignored(child, f"cannot be read because {e}")
+ normalized_path = normalize_path_maybe_ignore(child, root, report)
+ if normalized_path is None:
continue
- except ValueError:
- if child.is_symlink():
- report.path_ignored(
- child, f"is a symbolic link that points outside {root}"
- )
- continue
-
- raise
# First ignore files matching .gitignore
if gitignore.match_file(normalized_path):
report.path_ignored(child, "matches the .gitignore file content")
continue
+ # Then ignore with `--exclude` and `--force-exclude` options.
normalized_path = "/" + normalized_path
if child.is_dir():
normalized_path += "/"
- is_excluded = False
- for exclude in exclude_regexes:
- exclude_match = exclude.search(normalized_path) if exclude else None
- if exclude_match and exclude_match.group(0):
- report.path_ignored(child, "matches the --exclude regular expression")
- is_excluded = True
- break
- if is_excluded:
+ exclude_match = exclude.search(normalized_path) if exclude else None
+ if exclude_match and exclude_match.group(0):
+ report.path_ignored(child, "matches the --exclude regular expression")
+ continue
+
+ force_exclude_match = (
+ force_exclude.search(normalized_path) if force_exclude else None
+ )
+ if force_exclude_match and force_exclude_match.group(0):
+ report.path_ignored(child, "matches the --force-exclude regular expression")
continue
if child.is_dir():
yield from gen_python_files(
- child.iterdir(), root, include, exclude_regexes, report, gitignore
+ child.iterdir(),
+ root,
+ include,
+ exclude,
+ force_exclude,
+ report,
+ gitignore,
)
elif child.is_file():
def find_project_root(srcs: Iterable[str]) -> Path:
"""Return a directory containing .git, .hg, or pyproject.toml.
- That directory can be one of the directories passed in `srcs` or their
- common parent.
+ That directory will be a common parent of all files and directories
+ passed in `srcs`.
If no directory in the tree contains a marker that would specify it's the
project root, the root of the file system is returned.
if not srcs:
return Path("/").resolve()
- common_base = min(Path(src).resolve() for src in srcs)
- if common_base.is_dir():
- # Append a fake file so `parents` below returns `common_base_dir`, too.
- common_base /= "fake-file"
- for directory in common_base.parents:
+ path_srcs = [Path(Path.cwd(), src).resolve() for src in srcs]
+
+ # A list of lists of parents for each 'src'. 'src' is included as a
+ # "parent" of itself if it is a directory
+ src_parents = [
+ list(path.parents) + ([path] if path.is_dir() else []) for path in path_srcs
+ ]
+
+ common_base = max(
+ set.intersection(*(set(parents) for parents in src_parents)),
+ key=lambda path: path.parts,
+ )
+
+ for directory in (common_base, *common_base.parents):
if (directory / ".git").exists():
return directory
and field == "value"
and isinstance(value, str)
):
- normalized = re.sub(r" *\n[ \t]+", "\n ", value).strip()
+ normalized = re.sub(r" *\n[ \t]*", "\n", value).strip()
else:
normalized = value
yield f"{' ' * (depth+2)}{normalized!r}, # {value.__class__.__name__}"
newdst = format_str(dst, mode=mode)
if dst != newdst:
log = dump_to_file(
+ str(mode),
diff(src, dst, "source", "first pass"),
diff(dst, newdst, "first pass", "second pass"),
)
return True
-def can_omit_invisible_parens(line: Line, line_length: int) -> bool:
+def can_omit_invisible_parens(
+ line: Line,
+ line_length: int,
+ omit_on_explode: Collection[LeafID] = (),
+) -> bool:
"""Does `line` have a shape safe to reformat without optional parens around it?
Returns True for only a subset of potentially nice looking formattings but
assert len(line.leaves) >= 2, "Stranded delimiter"
- first = line.leaves[0]
- second = line.leaves[1]
- penultimate = line.leaves[-2]
- last = line.leaves[-1]
-
# With a single delimiter, omit if the expression starts or ends with
# a bracket.
+ first = line.leaves[0]
+ second = line.leaves[1]
if first.type in OPENING_BRACKETS and second.type not in CLOSING_BRACKETS:
- remainder = False
- length = 4 * line.depth
- for _index, leaf, leaf_length in enumerate_with_length(line):
- if leaf.type in CLOSING_BRACKETS and leaf.opening_bracket is first:
- remainder = True
- if remainder:
- length += leaf_length
- if length > line_length:
- break
-
- if leaf.type in OPENING_BRACKETS:
- # There are brackets we can further split on.
- remainder = False
-
- else:
- # checked the entire string and line length wasn't exceeded
- if len(line.leaves) == _index + 1:
- return True
+ if _can_omit_opening_paren(line, first=first, line_length=line_length):
+ return True
# Note: we are not returning False here because a line might have *both*
# a leading opening bracket and a trailing closing bracket. If the
# opening bracket doesn't match our rule, maybe the closing will.
+ penultimate = line.leaves[-2]
+ last = line.leaves[-1]
+ if line.should_explode:
+ try:
+ penultimate, last = last_two_except(line.leaves, omit=omit_on_explode)
+ except LookupError:
+ # Turns out we'd omit everything. We cannot skip the optional parentheses.
+ return False
+
if (
last.type == token.RPAR
or last.type == token.RBRACE
# unnecessary.
return True
- length = 4 * line.depth
- seen_other_brackets = False
- for _index, leaf, leaf_length in enumerate_with_length(line):
+ if line.should_explode and penultimate.type == token.COMMA:
+ # The rightmost non-omitted bracket pair is the one we want to explode on.
+ return True
+
+ if _can_omit_closing_paren(line, last=last, line_length=line_length):
+ return True
+
+ return False
+
+
+def _can_omit_opening_paren(line: Line, *, first: Leaf, line_length: int) -> bool:
+ """See `can_omit_invisible_parens`."""
+ remainder = False
+ length = 4 * line.depth
+ _index = -1
+ for _index, leaf, leaf_length in enumerate_with_length(line):
+ if leaf.type in CLOSING_BRACKETS and leaf.opening_bracket is first:
+ remainder = True
+ if remainder:
length += leaf_length
- if leaf is last.opening_bracket:
- if seen_other_brackets or length <= line_length:
- return True
+ if length > line_length:
+ break
- elif leaf.type in OPENING_BRACKETS:
+ if leaf.type in OPENING_BRACKETS:
# There are brackets we can further split on.
- seen_other_brackets = True
+ remainder = False
+
+ else:
+ # checked the entire string and line length wasn't exceeded
+ if len(line.leaves) == _index + 1:
+ return True
+
+ return False
+
+
+def _can_omit_closing_paren(line: Line, *, last: Leaf, line_length: int) -> bool:
+ """See `can_omit_invisible_parens`."""
+ length = 4 * line.depth
+ seen_other_brackets = False
+ for _index, leaf, leaf_length in enumerate_with_length(line):
+ length += leaf_length
+ if leaf is last.opening_bracket:
+ if seen_other_brackets or length <= line_length:
+ return True
+
+ elif leaf.type in OPENING_BRACKETS:
+ # There are brackets we can further split on.
+ seen_other_brackets = True
return False
+def last_two_except(leaves: List[Leaf], omit: Collection[LeafID]) -> Tuple[Leaf, Leaf]:
+ """Return (penultimate, last) leaves skipping brackets in `omit` and contents."""
+ stop_after = None
+ last = None
+ for leaf in reversed(leaves):
+ if stop_after:
+ if leaf is stop_after:
+ stop_after = None
+ continue
+
+ if last:
+ return leaf, last
+
+ if id(leaf) in omit:
+ stop_after = leaf.opening_bracket
+ else:
+ last = leaf
+ else:
+ raise LookupError("Last two leaves were also skipped")
+
+
+def run_transformer(
+ line: Line,
+ transform: Transformer,
+ mode: Mode,
+ features: Collection[Feature],
+ *,
+ line_str: str = "",
+) -> List[Line]:
+ if not line_str:
+ line_str = line_to_string(line)
+ result: List[Line] = []
+ for transformed_line in transform(line, features):
+ if str(transformed_line).strip("\n") == line_str:
+ raise CannotTransform("Line transformer returned an unchanged result")
+
+ 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)
+ ):
+ return result
+
+ line_copy = line.clone()
+ append_leaves(line_copy, line, line.leaves)
+ features_fop = set(features) | {Feature.FORCE_OPTIONAL_PARENTHESES}
+ second_opinion = run_transformer(
+ line_copy, transform, mode, features_fop, line_str=line_str
+ )
+ if all(
+ is_line_short_enough(ln, line_length=mode.line_length) for ln in second_opinion
+ ):
+ result = second_opinion
+ return result
+
+
def get_cache_file(mode: Mode) -> Path:
return CACHE_DIR / f"cache.{mode.get_cache_key()}.pickle"
main()
+def is_docstring(leaf: Leaf) -> bool:
+ if not is_multiline_string(leaf):
+ # For the purposes of docstring re-indentation, we don't need to do anything
+ # with single-line docstrings.
+ return False
+
+ if prev_siblings_are(
+ leaf.parent, [None, token.NEWLINE, token.INDENT, syms.simple_stmt]
+ ):
+ return True
+
+ # Multiline docstring on the same line as the `def`.
+ if prev_siblings_are(leaf.parent, [syms.parameters, token.COLON, syms.simple_stmt]):
+ # `syms.parameters` is only used in funcdefs and async_funcdefs in the Python
+ # grammar. We're safe to return True without further checks.
+ return True
+
+ return False
+
+
+def lines_with_leading_tabs_expanded(s: str) -> List[str]:
+ """
+ Splits string into lines and expands only leading tabs (following the normal
+ Python rules)
+ """
+ lines = []
+ for line in s.splitlines():
+ # Find the index of the first non-whitespace character after a string of
+ # whitespace that includes at least one tab
+ match = re.match(r"\s*\t+\s*(\S)", line)
+ if match:
+ first_non_whitespace_idx = match.start(1)
+
+ lines.append(
+ line[:first_non_whitespace_idx].expandtabs()
+ + line[first_non_whitespace_idx:]
+ )
+ else:
+ lines.append(line)
+ return lines
+
+
def fix_docstring(docstring: str, prefix: str) -> str:
# https://www.python.org/dev/peps/pep-0257/#handling-docstring-indentation
if not docstring:
return ""
- # Convert tabs to spaces (following the normal Python rules)
- # and split into a list of lines:
- lines = docstring.expandtabs().splitlines()
+ lines = lines_with_leading_tabs_expanded(docstring)
# Determine minimum indentation (first line doesn't count):
indent = sys.maxsize
for line in lines[1:]:
trimmed.append(prefix + stripped_line)
else:
trimmed.append("")
- # Return a single string:
return "\n".join(trimmed)