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
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,
+ },
}
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(
include: str,
exclude: str,
force_exclude: Optional[str],
+ stdin_filename: Optional[str],
src: Tuple[str, ...],
config: Optional[str],
) -> None:
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:
gitignore = get_gitignore(root)
for s in src:
- p = Path(s)
- if p.is_dir():
- sources.update(
- gen_python_files(
- p.iterdir(),
- root,
- include_regex,
- exclude_regex,
- force_exclude_regex,
- report,
- gitignore,
- )
- )
- elif s == "-":
- sources.add(p)
- elif p.is_file():
+ 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
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_regex,
+ force_exclude_regex,
+ report,
+ gitignore,
+ )
+ )
+ elif s == "-":
sources.add(p)
else:
err(f"invalid path: {s}")
"""
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:
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.
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:
...
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)
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
):
# 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
"""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.
* 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 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.
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)
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()
# 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
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.
for old_leaf in 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)
# 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:
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:
- 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
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:]: