from asyncio.base_events import BaseEventLoop
from concurrent.futures import Executor, ProcessPoolExecutor
from datetime import datetime
-from enum import Enum, Flag
+from enum import Enum
from functools import lru_cache, partial, wraps
import io
import itertools
-import keyword
import logging
from multiprocessing import Manager, freeze_support
import os
import re
import signal
import sys
+import tempfile
import tokenize
from typing import (
Any,
)
from appdirs import user_cache_dir
-from attr import dataclass, Factory
+from attr import dataclass, evolve, Factory
import click
import toml
from blib2to3.pytree import Node, Leaf, type_repr
from blib2to3 import pygram, pytree
from blib2to3.pgen2 import driver, token
+from blib2to3.pgen2.grammar import Grammar
from blib2to3.pgen2.parse import ParseError
-__version__ = "18.9b0"
+__version__ = "19.3b0"
DEFAULT_LINE_LENGTH = 88
DEFAULT_EXCLUDES = (
r"/(\.eggs|\.git|\.hg|\.mypy_cache|\.nox|\.tox|\.venv|_build|buck-out|build|dist)/"
Priority = int
Index = int
LN = Union[Leaf, Node]
-SplitFunc = Callable[["Line", bool], Iterator["Line"]]
+SplitFunc = Callable[["Line", Collection["Feature"]], Iterator["Line"]]
Timestamp = float
FileSize = int
CacheInfo = Tuple[Timestamp, FileSize]
YES = 2
-class FileMode(Flag):
- AUTO_DETECT = 0
- PYTHON36 = 1
- PYI = 2
- NO_STRING_NORMALIZATION = 4
- NO_NUMERIC_UNDERSCORE_NORMALIZATION = 8
+class TargetVersion(Enum):
+ PY27 = 2
+ PY33 = 3
+ PY34 = 4
+ PY35 = 5
+ PY36 = 6
+ PY37 = 7
+ PY38 = 8
+
+ 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
+ F_STRINGS = 2
+ NUMERIC_UNDERSCORES = 3
+ TRAILING_COMMA_IN_CALL = 4
+ TRAILING_COMMA_IN_DEF = 5
+
+
+VERSION_TO_FEATURES: Dict[TargetVersion, Set[Feature]] = {
+ TargetVersion.PY27: set(),
+ TargetVersion.PY33: {Feature.UNICODE_LITERALS},
+ TargetVersion.PY34: {Feature.UNICODE_LITERALS},
+ TargetVersion.PY35: {Feature.UNICODE_LITERALS, Feature.TRAILING_COMMA_IN_CALL},
+ TargetVersion.PY36: {
+ Feature.UNICODE_LITERALS,
+ Feature.F_STRINGS,
+ Feature.NUMERIC_UNDERSCORES,
+ Feature.TRAILING_COMMA_IN_CALL,
+ Feature.TRAILING_COMMA_IN_DEF,
+ },
+ TargetVersion.PY37: {
+ Feature.UNICODE_LITERALS,
+ Feature.F_STRINGS,
+ Feature.NUMERIC_UNDERSCORES,
+ Feature.TRAILING_COMMA_IN_CALL,
+ Feature.TRAILING_COMMA_IN_DEF,
+ },
+ TargetVersion.PY38: {
+ Feature.UNICODE_LITERALS,
+ Feature.F_STRINGS,
+ Feature.NUMERIC_UNDERSCORES,
+ Feature.TRAILING_COMMA_IN_CALL,
+ Feature.TRAILING_COMMA_IN_DEF,
+ },
+}
- @classmethod
- def from_configuration(
- cls,
- *,
- py36: bool,
- pyi: bool,
- skip_string_normalization: bool,
- skip_numeric_underscore_normalization: bool,
- ) -> "FileMode":
- mode = cls.AUTO_DETECT
- if py36:
- mode |= cls.PYTHON36
- if pyi:
- mode |= cls.PYI
- if skip_string_normalization:
- mode |= cls.NO_STRING_NORMALIZATION
- if skip_numeric_underscore_normalization:
- mode |= cls.NO_NUMERIC_UNDERSCORE_NORMALIZATION
- return mode
+
+@dataclass
+class FileMode:
+ target_versions: Set[TargetVersion] = Factory(set)
+ line_length: int = DEFAULT_LINE_LENGTH
+ string_normalization: bool = True
+ is_pyi: bool = False
+
+ def get_cache_key(self) -> str:
+ if self.target_versions:
+ version_str = ",".join(
+ str(version.value)
+ for version in sorted(self.target_versions, key=lambda v: v.value)
+ )
+ else:
+ version_str = "-"
+ parts = [
+ version_str,
+ str(self.line_length),
+ str(int(self.string_normalization)),
+ str(int(self.is_pyi)),
+ ]
+ return ".".join(parts)
+
+
+def supports_feature(target_versions: Set[TargetVersion], feature: Feature) -> bool:
+ return all(feature in VERSION_TO_FEATURES[version] for version in target_versions)
def read_pyproject_toml(
help="How many characters per line to allow.",
show_default=True,
)
+@click.option(
+ "-t",
+ "--target-version",
+ type=click.Choice([v.name.lower() for v in TargetVersion]),
+ callback=lambda c, p, v: [TargetVersion[val.upper()] for val in v],
+ multiple=True,
+ help=(
+ "Python versions that should be supported by Black's output. [default: "
+ "per-file auto-detection]"
+ ),
+)
@click.option(
"--py36",
is_flag=True,
help=(
"Allow using Python 3.6-only syntax on all input files. This will put "
"trailing commas in function signatures and calls also after *args and "
- "**kwargs. [default: per-file auto-detection]"
+ "**kwargs. Deprecated; use --target-version instead. "
+ "[default: per-file auto-detection]"
),
)
@click.option(
is_flag=True,
help="Don't normalize string quotes or prefixes.",
)
-@click.option(
- "-N",
- "--skip-numeric-underscore-normalization",
- is_flag=True,
- help="Don't normalize underscores in numeric literals.",
-)
@click.option(
"--check",
is_flag=True,
def main(
ctx: click.Context,
line_length: int,
+ target_version: List[TargetVersion],
check: bool,
diff: bool,
fast: bool,
pyi: bool,
py36: bool,
skip_string_normalization: bool,
- skip_numeric_underscore_normalization: bool,
quiet: bool,
verbose: bool,
include: str,
) -> None:
"""The uncompromising code formatter."""
write_back = WriteBack.from_configuration(check=check, diff=diff)
- mode = FileMode.from_configuration(
- py36=py36,
- pyi=pyi,
- skip_string_normalization=skip_string_normalization,
- skip_numeric_underscore_normalization=skip_numeric_underscore_normalization,
+ if target_version:
+ if py36:
+ err(f"Cannot use both --target-version and --py36")
+ ctx.exit(2)
+ else:
+ versions = set(target_version)
+ elif py36:
+ err(
+ "--py36 is deprecated and will be removed in a future version. "
+ "Use --target-version py36 instead."
+ )
+ versions = PY36_VERSIONS
+ else:
+ # We'll autodetect later.
+ versions = set()
+ mode = FileMode(
+ target_versions=versions,
+ line_length=line_length,
+ is_pyi=pyi,
+ string_normalization=not skip_string_normalization,
)
if config and verbose:
out(f"Using configuration from {config}.", bold=False, fg="blue")
if len(sources) == 1:
reformat_one(
src=sources.pop(),
- line_length=line_length,
fast=fast,
write_back=write_back,
mode=mode,
loop.run_until_complete(
schedule_formatting(
sources=sources,
- line_length=line_length,
fast=fast,
write_back=write_back,
mode=mode,
def reformat_one(
- src: Path,
- line_length: int,
- fast: bool,
- write_back: WriteBack,
- mode: FileMode,
- report: "Report",
+ src: Path, fast: bool, write_back: WriteBack, mode: FileMode, report: "Report"
) -> None:
"""Reformat a single file under `src` without spawning child processes.
try:
changed = Changed.NO
if not src.is_file() and str(src) == "-":
- if format_stdin_to_stdout(
- line_length=line_length, fast=fast, write_back=write_back, mode=mode
- ):
+ if format_stdin_to_stdout(fast=fast, write_back=write_back, mode=mode):
changed = Changed.YES
else:
cache: Cache = {}
if write_back != WriteBack.DIFF:
- cache = read_cache(line_length, mode)
+ cache = read_cache(mode)
res_src = src.resolve()
if res_src in cache and cache[res_src] == get_cache_info(res_src):
changed = Changed.CACHED
if changed is not Changed.CACHED and format_file_in_place(
- src,
- line_length=line_length,
- fast=fast,
- write_back=write_back,
- mode=mode,
+ src, fast=fast, write_back=write_back, mode=mode
):
changed = Changed.YES
if (write_back is WriteBack.YES and changed is not Changed.CACHED) or (
write_back is WriteBack.CHECK and changed is Changed.NO
):
- write_cache(cache, [src], line_length, mode)
+ write_cache(cache, [src], mode)
report.done(src, changed)
except Exception as exc:
report.failed(src, str(exc))
async def schedule_formatting(
sources: Set[Path],
- line_length: int,
fast: bool,
write_back: WriteBack,
mode: FileMode,
"""
cache: Cache = {}
if write_back != WriteBack.DIFF:
- cache = read_cache(line_length, mode)
+ cache = read_cache(mode)
sources, cached = filter_cached(cache, sources)
for src in sorted(cached):
report.done(src, Changed.CACHED)
manager = Manager()
lock = manager.Lock()
tasks = {
- loop.run_in_executor(
- executor,
- format_file_in_place,
- src,
- line_length,
- fast,
- write_back,
- mode,
- lock,
+ asyncio.ensure_future(
+ loop.run_in_executor(
+ executor, format_file_in_place, src, fast, mode, write_back, lock
+ )
): src
for src in sorted(sources)
}
- pending: Iterable[asyncio.Task] = tasks.keys()
+ pending: Iterable[asyncio.Future] = tasks.keys()
try:
loop.add_signal_handler(signal.SIGINT, cancel, pending)
loop.add_signal_handler(signal.SIGTERM, cancel, pending)
if cancelled:
await asyncio.gather(*cancelled, loop=loop, return_exceptions=True)
if sources_to_cache:
- write_cache(cache, sources_to_cache, line_length, mode)
+ write_cache(cache, sources_to_cache, mode)
def format_file_in_place(
src: Path,
- line_length: int,
fast: bool,
+ mode: FileMode,
write_back: WriteBack = WriteBack.NO,
- mode: FileMode = FileMode.AUTO_DETECT,
lock: Any = None, # multiprocessing.Manager().Lock() is some crazy proxy
) -> bool:
"""Format file under `src` path. Return True if changed.
`line_length` and `fast` options are passed to :func:`format_file_contents`.
"""
if src.suffix == ".pyi":
- mode |= FileMode.PYI
+ mode = evolve(mode, is_pyi=True)
then = datetime.utcfromtimestamp(src.stat().st_mtime)
with open(src, "rb") as buf:
src_contents, encoding, newline = decode_bytes(buf.read())
try:
- dst_contents = format_file_contents(
- src_contents, line_length=line_length, fast=fast, mode=mode
- )
+ dst_contents = format_file_contents(src_contents, fast=fast, mode=mode)
except NothingChanged:
return False
def format_stdin_to_stdout(
- line_length: int,
- fast: bool,
- write_back: WriteBack = WriteBack.NO,
- mode: FileMode = FileMode.AUTO_DETECT,
+ fast: bool, *, write_back: WriteBack = WriteBack.NO, mode: FileMode
) -> bool:
"""Format file on stdin. Return True if changed.
If `write_back` is YES, write reformatted code back to stdout. If it is DIFF,
- write a diff to stdout.
- `line_length`, `fast`, `is_pyi`, and `force_py36` arguments are passed to
+ write a diff to stdout. The `mode` argument is passed to
:func:`format_file_contents`.
"""
then = datetime.utcnow()
src, encoding, newline = decode_bytes(sys.stdin.buffer.read())
dst = src
try:
- dst = format_file_contents(src, line_length=line_length, fast=fast, mode=mode)
+ dst = format_file_contents(src, fast=fast, mode=mode)
return True
except NothingChanged:
def format_file_contents(
- src_contents: str,
- *,
- line_length: int,
- fast: bool,
- mode: FileMode = FileMode.AUTO_DETECT,
+ src_contents: str, *, fast: bool, mode: FileMode
) -> FileContent:
"""Reformat contents a file and return new contents.
if src_contents.strip() == "":
raise NothingChanged
- dst_contents = format_str(src_contents, line_length=line_length, mode=mode)
+ dst_contents = format_str(src_contents, mode=mode)
if src_contents == dst_contents:
raise NothingChanged
if not fast:
assert_equivalent(src_contents, dst_contents)
- assert_stable(src_contents, dst_contents, line_length=line_length, mode=mode)
+ assert_stable(src_contents, dst_contents, mode=mode)
return dst_contents
-def format_str(
- src_contents: str, line_length: int, *, mode: FileMode = FileMode.AUTO_DETECT
-) -> FileContent:
+def format_str(src_contents: str, *, mode: FileMode) -> FileContent:
"""Reformat a string and return new contents.
`line_length` determines how many characters per line are allowed.
"""
- src_node = lib2to3_parse(src_contents.lstrip())
+ src_node = lib2to3_parse(src_contents.lstrip(), mode.target_versions)
dst_contents = ""
future_imports = get_future_imports(src_node)
- is_pyi = bool(mode & FileMode.PYI)
- py36 = bool(mode & FileMode.PYTHON36) or is_python36(src_node)
- normalize_strings = not bool(mode & FileMode.NO_STRING_NORMALIZATION)
+ if mode.target_versions:
+ versions = mode.target_versions
+ else:
+ versions = detect_target_versions(src_node)
normalize_fmt_off(src_node)
lines = LineGenerator(
- remove_u_prefix=py36 or "unicode_literals" in future_imports,
- is_pyi=is_pyi,
- normalize_strings=normalize_strings,
- allow_underscores=py36
- and not bool(mode & FileMode.NO_NUMERIC_UNDERSCORE_NORMALIZATION),
+ remove_u_prefix="unicode_literals" in future_imports
+ or supports_feature(versions, Feature.UNICODE_LITERALS),
+ is_pyi=mode.is_pyi,
+ normalize_strings=mode.string_normalization,
)
- elt = EmptyLineTracker(is_pyi=is_pyi)
+ elt = EmptyLineTracker(is_pyi=mode.is_pyi)
empty_line = Line()
after = 0
+ split_line_features = {
+ feature
+ for feature in {Feature.TRAILING_COMMA_IN_CALL, Feature.TRAILING_COMMA_IN_DEF}
+ if supports_feature(versions, feature)
+ }
for current_line in lines.visit(src_node):
for _ in range(after):
dst_contents += str(empty_line)
before, after = elt.maybe_empty_lines(current_line)
for _ in range(before):
dst_contents += str(empty_line)
- for line in split_line(current_line, line_length=line_length, py36=py36):
+ for line in split_line(
+ current_line, line_length=mode.line_length, features=split_line_features
+ ):
dst_contents += str(line)
return dst_contents
return tiow.read(), encoding, newline
-GRAMMARS = [
- pygram.python_grammar_no_print_statement_no_exec_statement,
- pygram.python_grammar_no_print_statement,
- pygram.python_grammar,
-]
+def get_grammars(target_versions: Set[TargetVersion]) -> List[Grammar]:
+ if not target_versions:
+ # No target_version specified, so try all grammars.
+ return [
+ pygram.python_grammar_no_print_statement_no_exec_statement,
+ pygram.python_grammar_no_print_statement,
+ pygram.python_grammar,
+ ]
+ elif all(version.is_python2() for version in target_versions):
+ # Python 2-only code, so try Python 2 grammars.
+ return [pygram.python_grammar_no_print_statement, pygram.python_grammar]
+ else:
+ # Python 3-compatible code, so only try Python 3 grammar.
+ return [pygram.python_grammar_no_print_statement_no_exec_statement]
-def lib2to3_parse(src_txt: str) -> Node:
+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":
src_txt += "\n"
- for grammar in GRAMMARS:
+
+ for grammar in get_grammars(set(target_versions)):
drv = driver.Driver(grammar, pytree.convert)
try:
result = drv.parse_string(src_txt, True)
list(v.visit(code))
-KEYWORDS = set(keyword.kwlist)
WHITESPACE = {token.DEDENT, token.INDENT, token.NEWLINE}
-FLOW_CONTROL = {"return", "raise", "break", "continue"}
STATEMENT = {
syms.if_stmt,
syms.while_stmt,
depth: int = 0
leaves: List[Leaf] = Factory(list)
- # The LeafID keys of comments must remain ordered by the corresponding leaf's index
- # in leaves
- comments: Dict[LeafID, List[Leaf]] = Factory(dict)
+ comments: Dict[LeafID, List[Leaf]] = Factory(dict) # keys ordered like `leaves`
bracket_tracker: BracketTracker = Factory(BracketTracker)
inside_brackets: bool = False
should_explode: bool = False
if leaf.type == STANDALONE_COMMENT:
if leaf.bracket_depth <= depth_limit:
return True
+ return False
+
+ def contains_inner_type_comments(self) -> bool:
+ ignored_ids = set()
+ try:
+ last_leaf = self.leaves[-1]
+ ignored_ids.add(id(last_leaf))
+ if last_leaf.type == token.COMMA:
+ # When trailing commas are inserted by Black for consistency, comments
+ # after the previous last element are not moved (they don't have to,
+ # rendering will still be correct). So we ignore trailing commas.
+ last_leaf = self.leaves[-2]
+ ignored_ids.add(id(last_leaf))
+ except IndexError:
+ return False
+
+ for leaf_id, comments in self.comments.items():
+ if leaf_id in ignored_ids:
+ continue
+
+ for comment in comments:
+ if is_type_comment(comment):
+ return True
return False
comment.prefix = ""
return False
- else:
- leaf_id = id(self.leaves[-1])
- if leaf_id not in self.comments:
- self.comments[leaf_id] = [comment]
- else:
- self.comments[leaf_id].append(comment)
- return True
+ self.comments.setdefault(id(self.leaves[-1]), []).append(comment)
+ return True
def comments_after(self, leaf: Leaf) -> List[Leaf]:
"""Generate comments that should appear directly after `leaf`."""
def remove_trailing_comma(self) -> None:
"""Remove the trailing comma and moves the comments attached to it."""
- # Remember, the LeafID keys of self.comments are ordered by the
- # corresponding leaf's index in self.leaves
- # If id(self.leaves[-2]) is in self.comments, the order doesn't change.
- # Otherwise, we insert it into self.comments, and it becomes the last entry.
- # However, since we delete id(self.leaves[-1]) from self.comments, the invariant
- # is maintained
- self.comments.setdefault(id(self.leaves[-2]), []).extend(
- self.comments.get(id(self.leaves[-1]), [])
+ trailing_comma = self.leaves.pop()
+ trailing_comma_comments = self.comments.pop(id(trailing_comma), [])
+ self.comments.setdefault(id(self.leaves[-1]), []).extend(
+ trailing_comma_comments
)
- self.comments.pop(id(self.leaves[-1]), None)
- self.leaves.pop()
def is_complex_subscript(self, leaf: Leaf) -> bool:
"""Return True iff `leaf` is part of a slice with non-trivial exprs."""
normalize_strings: bool = True
current_line: Line = Factory(Line)
remove_u_prefix: bool = False
- allow_underscores: bool = False
def line(self, indent: int = 0) -> Iterator[Line]:
"""Generate a line.
normalize_string_prefix(node, remove_u_prefix=self.remove_u_prefix)
normalize_string_quotes(node)
if node.type == token.NUMBER:
- normalize_numeric_literal(node, self.allow_underscores)
+ normalize_numeric_literal(node)
if node.type not in WHITESPACE:
self.current_line.append(node)
yield from super().visit_default(node)
self.visit_expr_stmt = partial(v, keywords=Ø, parens=ASSIGNMENTS)
self.visit_return_stmt = partial(v, keywords={"return"}, parens={"return"})
self.visit_import_from = partial(v, keywords=Ø, parens={"import"})
+ self.visit_del_stmt = partial(v, keywords=Ø, parens={"del"})
self.visit_async_funcdef = self.visit_async_stmt
self.visit_decorated = self.visit_decorators
ALWAYS_NO_SPACE = CLOSING_BRACKETS | {token.COMMA, STANDALONE_COMMENT}
-def whitespace(leaf: Leaf, *, complex_subscript: bool) -> str: # noqa C901
+def whitespace(leaf: Leaf, *, complex_subscript: bool) -> str: # noqa: C901
"""Return whitespace prefix if needed for the given `leaf`.
`complex_subscript` signals whether the given leaf is part of a subscription
def split_line(
- line: Line, line_length: int, inner: bool = False, py36: bool = False
+ line: Line,
+ line_length: int,
+ inner: bool = False,
+ features: Collection[Feature] = (),
) -> Iterator[Line]:
"""Split a `line` into potentially many lines.
current `line`, possibly transitively. This means we can fallback to splitting
by delimiters if the LHS/RHS don't yield any results.
- If `py36` is True, splitting may generate syntax that is only compatible
- with Python 3.6 and later.
+ `features` are syntactical features that may be used in the output.
"""
if line.is_comment:
yield line
return
line_str = str(line).strip("\n")
- if not line.should_explode and is_line_short_enough(
- line, line_length=line_length, line_str=line_str
+
+ if (
+ not line.contains_inner_type_comments()
+ and not line.should_explode
+ and is_line_short_enough(line, line_length=line_length, line_str=line_str)
):
yield line
return
split_funcs = [left_hand_split]
else:
- def rhs(line: Line, py36: bool = False) -> Iterator[Line]:
+ 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, py36, omit=omit))
+ lines = list(right_hand_split(line, line_length, features, omit=omit))
if is_line_short_enough(lines[0], line_length=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.
- yield from right_hand_split(line, py36)
+ yield from right_hand_split(line, line_length, features=features)
if line.inside_brackets:
split_funcs = [delimiter_split, standalone_comment_split, rhs]
# split altogether.
result: List[Line] = []
try:
- for l in split_func(line, py36):
+ for l in split_func(line, features):
if str(l).strip("\n") == line_str:
raise CannotSplit("Split function returned an unchanged result")
result.extend(
- split_line(l, line_length=line_length, inner=True, py36=py36)
+ split_line(
+ l, line_length=line_length, inner=True, features=features
+ )
)
except CannotSplit:
continue
yield line
-def left_hand_split(line: Line, py36: bool = False) -> Iterator[Line]:
+def left_hand_split(line: Line, features: Collection[Feature] = ()) -> Iterator[Line]:
"""Split line into many lines, starting with the first matching bracket pair.
Note: this usually looks weird, only use this for function definitions.
def right_hand_split(
- line: Line, line_length: int, py36: bool = False, omit: Collection[LeafID] = ()
+ line: Line,
+ line_length: int,
+ features: Collection[Feature] = (),
+ omit: Collection[LeafID] = (),
) -> Iterator[Line]:
"""Split line into many lines, starting with the last matching bracket pair.
):
omit = {id(closing_bracket), *omit}
try:
- yield from right_hand_split(line, line_length, py36=py36, omit=omit)
+ yield from right_hand_split(line, line_length, features=features, omit=omit)
return
except CannotSplit:
if leaves:
# Since body is a new indent level, remove spurious leading whitespace.
normalize_prefix(leaves[0], inside_brackets=True)
- # Ensure a trailing comma when expected.
+ # Ensure a trailing comma for imports, but be careful not to add one after
+ # any comments.
if original.is_import:
- if leaves[-1].type != token.COMMA:
- leaves.append(Leaf(token.COMMA, ","))
+ for i in range(len(leaves) - 1, -1, -1):
+ if leaves[i].type == STANDALONE_COMMENT:
+ continue
+ elif leaves[i].type == token.COMMA:
+ break
+ else:
+ leaves.insert(i + 1, Leaf(token.COMMA, ","))
+ break
# Populate the line
for leaf in leaves:
result.append(leaf, preformatted=True)
"""
@wraps(split_func)
- def split_wrapper(line: Line, py36: bool = False) -> Iterator[Line]:
- for l in split_func(line, py36):
+ def split_wrapper(line: Line, features: Collection[Feature] = ()) -> Iterator[Line]:
+ for l in split_func(line, features):
normalize_prefix(l.leaves[0], inside_brackets=True)
yield l
@dont_increase_indentation
-def delimiter_split(line: Line, py36: bool = False) -> Iterator[Line]:
+def delimiter_split(line: Line, features: Collection[Feature] = ()) -> Iterator[Line]:
"""Split according to delimiters of the highest priority.
- If `py36` is True, the split will add trailing commas also in function
- signatures that contain `*` and `**`.
+ If the appropriate Features are given, the split will add trailing commas
+ also in function signatures and calls that contain `*` and `**`.
"""
try:
last_leaf = line.leaves[-1]
yield from append_to_line(comment_after)
lowest_depth = min(lowest_depth, leaf.bracket_depth)
- if leaf.bracket_depth == lowest_depth and is_vararg(
- leaf, within=VARARGS_PARENTS
- ):
- trailing_comma_safe = trailing_comma_safe and py36
+ if leaf.bracket_depth == lowest_depth:
+ if is_vararg(leaf, within={syms.typedargslist}):
+ trailing_comma_safe = (
+ trailing_comma_safe and Feature.TRAILING_COMMA_IN_DEF in features
+ )
+ elif is_vararg(leaf, within={syms.arglist, syms.argument}):
+ trailing_comma_safe = (
+ trailing_comma_safe and Feature.TRAILING_COMMA_IN_CALL in features
+ )
+
leaf_priority = bt.delimiters.get(id(leaf))
if leaf_priority == delimiter_priority:
yield current_line
@dont_increase_indentation
-def standalone_comment_split(line: Line, py36: bool = False) -> Iterator[Line]:
+def standalone_comment_split(
+ line: Line, features: Collection[Feature] = ()
+) -> Iterator[Line]:
"""Split standalone comments from the rest of the line."""
if not line.contains_standalone_comments(0):
raise CannotSplit("Line does not have any standalone comments")
)
+def is_type_comment(leaf: Leaf) -> bool:
+ """Return True if the given leaf is a special comment.
+ Only returns true for type comments for now."""
+ t = leaf.type
+ v = leaf.value
+ return t in {token.COMMENT, t == STANDALONE_COMMENT} and v.startswith("# type:")
+
+
def normalize_prefix(leaf: Leaf, *, inside_brackets: bool) -> None:
"""Leave existing extra newlines if not `inside_brackets`. Remove everything
else.
leaf.value = f"{prefix}{new_quote}{new_body}{new_quote}"
-def normalize_numeric_literal(leaf: Leaf, allow_underscores: bool) -> None:
+def normalize_numeric_literal(leaf: Leaf) -> None:
"""Normalizes numeric (float, int, and complex) literals.
All letters used in the representation are normalized to lowercase (except
- in Python 2 long literals), and long number literals are split using underscores.
+ in Python 2 long literals).
"""
text = leaf.value.lower()
if text.startswith(("0o", "0b")):
sign = "-"
elif after.startswith("+"):
after = after[1:]
- before = format_float_or_int_string(before, allow_underscores)
- after = format_int_string(after, allow_underscores)
+ before = format_float_or_int_string(before)
text = f"{before}e{sign}{after}"
elif text.endswith(("j", "l")):
number = 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, allow_underscores)}{suffix}"
+ text = f"{format_float_or_int_string(number)}{suffix}"
else:
- text = format_float_or_int_string(text, allow_underscores)
+ text = format_float_or_int_string(text)
leaf.value = text
-def format_float_or_int_string(text: str, allow_underscores: bool) -> str:
+def format_float_or_int_string(text: str) -> str:
"""Formats a float string like "1.0"."""
if "." not in text:
- return format_int_string(text, allow_underscores)
-
- before, after = text.split(".")
- before = format_int_string(before, allow_underscores) if before else "0"
- if after:
- after = format_int_string(after, allow_underscores, count_from_end=False)
- else:
- after = "0"
- return f"{before}.{after}"
-
-
-def format_int_string(
- text: str, allow_underscores: bool, count_from_end: bool = True
-) -> str:
- """Normalizes underscores in a string to e.g. 1_000_000.
-
- Input must be a string of digits and optional underscores.
- If count_from_end is False, we add underscores after groups of three digits
- counting from the beginning instead of the end of the strings. This is used
- for the fractional part of float literals.
- """
- if not allow_underscores:
- return text
-
- text = text.replace("_", "")
- if len(text) <= 5:
- # No underscores for numbers <= 5 digits long.
return text
- if count_from_end:
- # Avoid removing leading zeros, which are important if we're formatting
- # part of a number like "0.001".
- return format(int("1" + text), "3_")[1:].lstrip("_")
- else:
- return "_".join(text[i : i + 3] for i in range(0, len(text), 3))
+ before, after = text.split(".")
+ return f"{before or 0}.{after or 0}"
def normalize_invisible_parens(node: Node, parens_after: Set[str]) -> None:
def should_explode(line: Line, opening_bracket: Leaf) -> bool:
"""Should `line` immediately be split with `delimiter_split()` after RHS?"""
+
if not (
opening_bracket.parent
and opening_bracket.parent.type in {syms.atom, syms.import_from}
return max_priority == COMMA_PRIORITY
-def is_python36(node: Node) -> bool:
- """Return True if the current file is using Python 3.6+ features.
+def get_features_used(node: Node) -> Set[Feature]:
+ """Return a set of (relatively) new Python features used in this file.
Currently looking for:
- f-strings;
- underscores in numeric literals; and
- trailing commas after * or ** in function signatures and calls.
"""
+ features: Set[Feature] = set()
for n in node.pre_order():
if n.type == token.STRING:
value_head = n.value[:2] # type: ignore
if value_head in {'f"', 'F"', "f'", "F'", "rf", "fr", "RF", "FR"}:
- return True
+ features.add(Feature.F_STRINGS)
elif n.type == token.NUMBER:
if "_" in n.value: # type: ignore
- return True
+ features.add(Feature.NUMERIC_UNDERSCORES)
elif (
n.type in {syms.typedargslist, syms.arglist}
and n.children
and n.children[-1].type == token.COMMA
):
+ if n.type == syms.typedargslist:
+ feature = Feature.TRAILING_COMMA_IN_DEF
+ else:
+ feature = Feature.TRAILING_COMMA_IN_CALL
+
for ch in n.children:
if ch.type in STARS:
- return True
+ features.add(feature)
if ch.type == syms.argument:
for argch in ch.children:
if argch.type in STARS:
- return True
+ features.add(feature)
- return False
+ return features
+
+
+def detect_target_versions(node: Node) -> Set[TargetVersion]:
+ """Detect the version to target based on the nodes used."""
+ features = get_features_used(node)
+ return {
+ version for version in TargetVersion if features <= VERSION_TO_FEATURES[version]
+ }
def generate_trailers_to_omit(line: Line, line_length: int) -> Iterator[Set[LeafID]]:
elif child.type == syms.import_as_names:
yield from get_imports_from_children(child.children)
else:
- assert False, "Invalid syntax parsing imports"
+ raise AssertionError("Invalid syntax parsing imports")
for child in node.children:
if child.type != syms.simple_stmt:
if isinstance(value, list):
for item in value:
- if isinstance(item, ast.AST):
+ # Ignore nested tuples within del statements, because we may insert
+ # parentheses and they change the AST.
+ if (
+ field == "targets"
+ and isinstance(node, ast.Delete)
+ and isinstance(item, ast.Tuple)
+ ):
+ for item in item.elts:
+ yield from _v(item, depth + 2)
+ elif isinstance(item, ast.AST):
yield from _v(item, depth + 2)
elif isinstance(value, ast.AST):
log = dump_to_file("".join(traceback.format_tb(exc.__traceback__)), dst)
raise AssertionError(
f"INTERNAL ERROR: Black produced invalid code: {exc}. "
- f"Please report a bug on https://github.com/ambv/black/issues. "
+ f"Please report a bug on https://github.com/python/black/issues. "
f"This invalid output might be helpful: {log}"
) from None
raise AssertionError(
f"INTERNAL ERROR: Black produced code that is not equivalent to "
f"the source. "
- f"Please report a bug on https://github.com/ambv/black/issues. "
+ f"Please report a bug on https://github.com/python/black/issues. "
f"This diff might be helpful: {log}"
) from None
-def assert_stable(
- src: str, dst: str, line_length: int, mode: FileMode = FileMode.AUTO_DETECT
-) -> None:
+def assert_stable(src: str, dst: str, mode: FileMode) -> None:
"""Raise AssertionError if `dst` reformats differently the second time."""
- newdst = format_str(dst, line_length=line_length, mode=mode)
+ newdst = format_str(dst, mode=mode)
if dst != newdst:
log = dump_to_file(
diff(src, dst, "source", "first pass"),
raise AssertionError(
f"INTERNAL ERROR: Black produced different code on the second pass "
f"of the formatter. "
- f"Please report a bug on https://github.com/ambv/black/issues. "
+ f"Please report a bug on https://github.com/python/black/issues. "
f"This diff might be helpful: {log}"
) from None
def shutdown(loop: BaseEventLoop) -> None:
"""Cancel all pending tasks on `loop`, wait for them, and close the loop."""
try:
+ if sys.version_info[:2] >= (3, 7):
+ all_tasks = asyncio.all_tasks
+ else:
+ all_tasks = asyncio.Task.all_tasks
# This part is borrowed from asyncio/runners.py in Python 3.7b2.
- to_cancel = [task for task in asyncio.Task.all_tasks(loop) if not task.done()]
+ to_cancel = [task for task in all_tasks(loop) if not task.done()]
if not to_cancel:
return
return False
-def get_cache_file(line_length: int, mode: FileMode) -> Path:
- return CACHE_DIR / f"cache.{line_length}.{mode.value}.pickle"
+def get_cache_file(mode: FileMode) -> Path:
+ return CACHE_DIR / f"cache.{mode.get_cache_key()}.pickle"
-def read_cache(line_length: int, mode: FileMode) -> Cache:
+def read_cache(mode: FileMode) -> Cache:
"""Read the cache if it exists and is well formed.
If it is not well formed, the call to write_cache later should resolve the issue.
"""
- cache_file = get_cache_file(line_length, mode)
+ cache_file = get_cache_file(mode)
if not cache_file.exists():
return {}
return todo, done
-def write_cache(
- cache: Cache, sources: Iterable[Path], line_length: int, mode: FileMode
-) -> None:
+def write_cache(cache: Cache, sources: Iterable[Path], mode: FileMode) -> None:
"""Update the cache file."""
- cache_file = get_cache_file(line_length, mode)
+ cache_file = get_cache_file(mode)
try:
- if not CACHE_DIR.exists():
- CACHE_DIR.mkdir(parents=True)
+ CACHE_DIR.mkdir(parents=True, exist_ok=True)
new_cache = {**cache, **{src.resolve(): get_cache_info(src) for src in sources}}
- with cache_file.open("wb") as fobj:
- pickle.dump(new_cache, fobj, protocol=pickle.HIGHEST_PROTOCOL)
+ with tempfile.NamedTemporaryFile(dir=str(cache_file.parent), delete=False) as f:
+ pickle.dump(new_cache, f, protocol=pickle.HIGHEST_PROTOCOL)
+ os.replace(f.name, cache_file)
except OSError:
pass