X-Git-Url: https://git.madduck.net/etc/vim.git/blobdiff_plain/77b6ed1b70bd07f058bc551906bc880022847964..154b98579d3904a042fd3e02a9d77a76be63b36c:/black.py?ds=inline diff --git a/black.py b/black.py index 180163c..05edf1a 100644 --- a/black.py +++ b/black.py @@ -1,3 +1,4 @@ +import ast import asyncio from concurrent.futures import Executor, ProcessPoolExecutor from contextlib import contextmanager @@ -141,6 +142,8 @@ class Feature(Enum): # set for every version of python. ASYNC_IDENTIFIERS = 6 ASYNC_KEYWORDS = 7 + ASSIGNMENT_EXPRESSIONS = 8 + POS_ONLY_ARGUMENTS = 9 VERSION_TO_FEATURES: Dict[TargetVersion, Set[Feature]] = { @@ -175,6 +178,8 @@ VERSION_TO_FEATURES: Dict[TargetVersion, Set[Feature]] = { Feature.TRAILING_COMMA_IN_CALL, Feature.TRAILING_COMMA_IN_DEF, Feature.ASYNC_KEYWORDS, + Feature.ASSIGNMENT_EXPRESSIONS, + Feature.POS_ONLY_ARGUMENTS, }, } @@ -932,6 +937,7 @@ MATH_OPERATORS = { token.DOUBLESTAR, } STARS = {token.STAR, token.DOUBLESTAR} +VARARGS_SPECIALS = STARS | {token.SLASH} VARARGS_PARENTS = { syms.arglist, syms.argument, # double star in arglist @@ -1474,7 +1480,13 @@ class EmptyLineTracker: lines (two on module-level). """ before, after = self._maybe_empty_lines(current_line) - before -= self.previous_after + before = ( + # Black should not insert empty lines at the beginning + # of the file + 0 + if self.previous_line is None + else before - self.previous_after + ) self.previous_after = after self.previous_line = current_line return before, after @@ -1844,7 +1856,7 @@ def whitespace(leaf: Leaf, *, complex_subscript: bool) -> str: # noqa: C901 # that, too. return prevp.prefix - elif prevp.type in STARS: + elif prevp.type in VARARGS_SPECIALS: if is_vararg(prevp, within=VARARGS_PARENTS | UNPACKING_PARENTS): return NO @@ -1934,7 +1946,7 @@ def whitespace(leaf: Leaf, *, complex_subscript: bool) -> str: # noqa: C901 if not prevp or prevp.type == token.LPAR: return NO - elif prev.type in {token.EQUAL} | STARS: + elif prev.type in {token.EQUAL} | VARARGS_SPECIALS: return NO elif p.type == syms.decorator: @@ -2863,6 +2875,8 @@ def normalize_invisible_parens(node: Node, parens_after: Set[str]) -> None: check_lpar = True if check_lpar: + if is_walrus_assignment(child): + continue if child.type == syms.atom: if maybe_make_parens_invisible_in_atom(child, parent=node): lpar = Leaf(token.LPAR, "") @@ -3000,8 +3014,7 @@ def maybe_make_parens_invisible_in_atom(node: LN, parent: LN) -> bool: # make parentheses invisible first.value = "" # type: ignore last.value = "" # type: ignore - if len(node.children) > 1: - maybe_make_parens_invisible_in_atom(node.children[1], parent=parent) + maybe_make_parens_invisible_in_atom(node.children[1], parent=parent) return False return True @@ -3017,18 +3030,24 @@ def is_empty_tuple(node: LN) -> bool: ) +def unwrap_singleton_parenthesis(node: LN) -> Optional[LN]: + """Returns `wrapped` if `node` is of the shape ( wrapped ). + + Parenthesis can be optional. Returns None otherwise""" + if len(node.children) != 3: + return None + lpar, wrapped, rpar = node.children + if not (lpar.type == token.LPAR and rpar.type == token.RPAR): + return None + + return wrapped + + def is_one_tuple(node: LN) -> bool: """Return True if `node` holds a tuple with one element, with or without parens.""" if node.type == syms.atom: - if len(node.children) != 3: - return False - - lpar, gexp, rpar = node.children - if not ( - lpar.type == token.LPAR - and gexp.type == syms.testlist_gexp - and rpar.type == token.RPAR - ): + gexp = unwrap_singleton_parenthesis(node) + if gexp is None or gexp.type != syms.testlist_gexp: return False return len(gexp.children) == 2 and gexp.children[1].type == token.COMMA @@ -3040,6 +3059,12 @@ def is_one_tuple(node: LN) -> bool: ) +def is_walrus_assignment(node: LN) -> bool: + """Return True iff `node` is of the shape ( test := test )""" + inner = unwrap_singleton_parenthesis(node) + return inner is not None and inner.type == syms.namedexpr_test + + def is_yield(node: LN) -> bool: """Return True if `node` holds a `yield` or `yield from` expression.""" if node.type == syms.yield_expr: @@ -3069,7 +3094,7 @@ def is_vararg(leaf: Leaf, within: Set[NodeType]) -> bool: extended iterable unpacking (PEP 3132) and additional unpacking generalizations (PEP 448). """ - if leaf.type not in STARS or not leaf.parent: + if leaf.type not in VARARGS_SPECIALS or not leaf.parent: return False p = leaf.parent @@ -3184,8 +3209,9 @@ def get_features_used(node: Node) -> Set[Feature]: Currently looking for: - f-strings; - - underscores in numeric literals; and - - trailing commas after * or ** in function signatures and calls. + - underscores in numeric literals; + - trailing commas after * or ** in function signatures and calls; + - positional only arguments in function signatures and lambdas; """ features: Set[Feature] = set() for n in node.pre_order(): @@ -3198,6 +3224,13 @@ def get_features_used(node: Node) -> Set[Feature]: if "_" in n.value: # type: ignore features.add(Feature.NUMERIC_UNDERSCORES) + elif n.type == token.SLASH: + if n.parent and n.parent.type in {syms.typedargslist, syms.arglist}: + features.add(Feature.POS_ONLY_ARGUMENTS) + + elif n.type == token.COLONEQUAL: + features.add(Feature.ASSIGNMENT_EXPRESSIONS) + elif ( n.type in {syms.typedargslist, syms.arglist} and n.children @@ -3479,32 +3512,58 @@ class Report: return ", ".join(report) + "." -def parse_ast(src: str) -> Union[ast3.AST, ast27.AST]: - for feature_version in (7, 6): - try: - return ast3.parse(src, feature_version=feature_version) - except SyntaxError: - continue +def parse_ast(src: str) -> Union[ast.AST, ast3.AST, ast27.AST]: + filename = "" + if sys.version_info >= (3, 8): + # TODO: support Python 4+ ;) + for minor_version in range(sys.version_info[1], 4, -1): + try: + return ast.parse(src, filename, feature_version=(3, minor_version)) + except SyntaxError: + continue + else: + for feature_version in (7, 6): + try: + return ast3.parse(src, filename, feature_version=feature_version) + except SyntaxError: + continue return ast27.parse(src) +def _fixup_ast_constants( + node: Union[ast.AST, ast3.AST, ast27.AST] +) -> Union[ast.AST, ast3.AST, ast27.AST]: + """Map ast nodes deprecated in 3.8 to Constant.""" + # casts are required until this is released: + # https://github.com/python/typeshed/pull/3142 + if isinstance(node, (ast.Str, ast3.Str, ast27.Str, ast.Bytes, ast3.Bytes)): + return cast(ast.AST, ast.Constant(value=node.s)) + elif isinstance(node, (ast.Num, ast3.Num, ast27.Num)): + return cast(ast.AST, ast.Constant(value=node.n)) + elif isinstance(node, (ast.NameConstant, ast3.NameConstant)): + return cast(ast.AST, ast.Constant(value=node.value)) + return node + + def assert_equivalent(src: str, dst: str) -> None: """Raise AssertionError if `src` and `dst` aren't equivalent.""" - def _v(node: Union[ast3.AST, ast27.AST], depth: int = 0) -> Iterator[str]: + def _v(node: Union[ast.AST, ast3.AST, ast27.AST], depth: int = 0) -> Iterator[str]: """Simple visitor generating strings to compare ASTs by content.""" + + node = _fixup_ast_constants(node) + yield f"{' ' * depth}{node.__class__.__name__}(" for field in sorted(node._fields): # TypeIgnore has only one field 'lineno' which breaks this comparison - if isinstance(node, (ast3.TypeIgnore, ast27.TypeIgnore)): + type_ignore_classes = (ast3.TypeIgnore, ast27.TypeIgnore) + if sys.version_info >= (3, 8): + type_ignore_classes += (ast.TypeIgnore,) + if isinstance(node, type_ignore_classes): break - # Ignore str kind which is case sensitive / and ignores unicode_literals - if isinstance(node, (ast3.Str, ast27.Str, ast3.Bytes)) and field == "kind": - continue - try: value = getattr(node, field) except AttributeError: @@ -3518,15 +3577,15 @@ def assert_equivalent(src: str, dst: str) -> None: # parentheses and they change the AST. if ( field == "targets" - and isinstance(node, (ast3.Delete, ast27.Delete)) - and isinstance(item, (ast3.Tuple, ast27.Tuple)) + and isinstance(node, (ast.Delete, ast3.Delete, ast27.Delete)) + and isinstance(item, (ast.Tuple, ast3.Tuple, ast27.Tuple)) ): for item in item.elts: yield from _v(item, depth + 2) - elif isinstance(item, (ast3.AST, ast27.AST)): + elif isinstance(item, (ast.AST, ast3.AST, ast27.AST)): yield from _v(item, depth + 2) - elif isinstance(value, (ast3.AST, ast27.AST)): + elif isinstance(value, (ast.AST, ast3.AST, ast27.AST)): yield from _v(value, depth + 2) else: