From cea13f498418784e22f8fbd78db3f9240a2bad11 Mon Sep 17 00:00:00 2001 From: Jelle Zijlstra Date: Mon, 25 Mar 2019 08:22:02 -0700 Subject: [PATCH 1/1] Split the TRAILING_COMMA feature (#763) --- black.py | 98 ++++++++++++++++++++++----------------------- tests/test_black.py | 23 ++++++----- 2 files changed, 63 insertions(+), 58 deletions(-) diff --git a/black.py b/black.py index 2dee826..0ea9b9a 100644 --- a/black.py +++ b/black.py @@ -68,7 +68,7 @@ LeafID = int 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] @@ -133,31 +133,35 @@ class Feature(Enum): UNICODE_LITERALS = 1 F_STRINGS = 2 NUMERIC_UNDERSCORES = 3 - TRAILING_COMMA = 4 + 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}, + TargetVersion.PY35: {Feature.UNICODE_LITERALS, Feature.TRAILING_COMMA_IN_CALL}, TargetVersion.PY36: { Feature.UNICODE_LITERALS, Feature.F_STRINGS, Feature.NUMERIC_UNDERSCORES, - Feature.TRAILING_COMMA, + Feature.TRAILING_COMMA_IN_CALL, + Feature.TRAILING_COMMA_IN_DEF, }, TargetVersion.PY37: { Feature.UNICODE_LITERALS, Feature.F_STRINGS, Feature.NUMERIC_UNDERSCORES, - Feature.TRAILING_COMMA, + Feature.TRAILING_COMMA_IN_CALL, + Feature.TRAILING_COMMA_IN_DEF, }, TargetVersion.PY38: { Feature.UNICODE_LITERALS, Feature.F_STRINGS, Feature.NUMERIC_UNDERSCORES, - Feature.TRAILING_COMMA, + Feature.TRAILING_COMMA_IN_CALL, + Feature.TRAILING_COMMA_IN_DEF, }, } @@ -683,6 +687,11 @@ def format_str(src_contents: str, *, mode: FileMode) -> FileContent: 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) @@ -690,9 +699,7 @@ def format_str(src_contents: str, *, mode: FileMode) -> FileContent: for _ in range(before): dst_contents += str(empty_line) for line in split_line( - current_line, - line_length=mode.line_length, - supports_trailing_commas=supports_feature(versions, Feature.TRAILING_COMMA), + current_line, line_length=mode.line_length, features=split_line_features ): dst_contents += str(line) return dst_contents @@ -2158,7 +2165,7 @@ def split_line( line: Line, line_length: int, inner: bool = False, - supports_trailing_commas: bool = False, + features: Collection[Feature] = (), ) -> Iterator[Line]: """Split a `line` into potentially many lines. @@ -2167,7 +2174,7 @@ def split_line( current `line`, possibly transitively. This means we can fallback to splitting by delimiters if the LHS/RHS don't yield any results. - If `supports_trailing_commas` is True, splitting may use the TRAILING_COMMA feature. + `features` are syntactical features that may be used in the output. """ if line.is_comment: yield line @@ -2188,13 +2195,9 @@ def split_line( split_funcs = [left_hand_split] else: - def rhs(line: Line, supports_trailing_commas: 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, supports_trailing_commas, 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 @@ -2202,7 +2205,7 @@ def split_line( # 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, line_length, supports_trailing_commas) + yield from right_hand_split(line, line_length, features=features) if line.inside_brackets: split_funcs = [delimiter_split, standalone_comment_split, rhs] @@ -2214,16 +2217,13 @@ def split_line( # split altogether. result: List[Line] = [] try: - for l in split_func(line, supports_trailing_commas): + 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, - supports_trailing_commas=supports_trailing_commas, + l, line_length=line_length, inner=True, features=features ) ) except CannotSplit: @@ -2237,9 +2237,7 @@ def split_line( yield line -def left_hand_split( - line: Line, supports_trailing_commas: 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. @@ -2278,7 +2276,7 @@ def left_hand_split( def right_hand_split( line: Line, line_length: int, - supports_trailing_commas: bool = False, + features: Collection[Feature] = (), omit: Collection[LeafID] = (), ) -> Iterator[Line]: """Split line into many lines, starting with the last matching bracket pair. @@ -2337,12 +2335,7 @@ def right_hand_split( ): omit = {id(closing_bracket), *omit} try: - yield from right_hand_split( - line, - line_length, - supports_trailing_commas=supports_trailing_commas, - omit=omit, - ) + yield from right_hand_split(line, line_length, features=features, omit=omit) return except CannotSplit: @@ -2431,10 +2424,8 @@ def dont_increase_indentation(split_func: SplitFunc) -> SplitFunc: """ @wraps(split_func) - def split_wrapper( - line: Line, supports_trailing_commas: bool = False - ) -> Iterator[Line]: - for l in split_func(line, supports_trailing_commas): + 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 @@ -2442,13 +2433,11 @@ def dont_increase_indentation(split_func: SplitFunc) -> SplitFunc: @dont_increase_indentation -def delimiter_split( - line: Line, supports_trailing_commas: bool = False -) -> Iterator[Line]: +def delimiter_split(line: Line, features: Collection[Feature] = ()) -> Iterator[Line]: """Split according to delimiters of the highest priority. - If `supports_trailing_commas` 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] @@ -2487,10 +2476,16 @@ def delimiter_split( 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 supports_trailing_commas + 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 @@ -2509,7 +2504,7 @@ def delimiter_split( @dont_increase_indentation def standalone_comment_split( - line: Line, supports_trailing_commas: bool = False + line: Line, features: Collection[Feature] = () ) -> Iterator[Line]: """Split standalone comments from the rest of the line.""" if not line.contains_standalone_comments(0): @@ -3059,14 +3054,19 @@ def get_features_used(node: Node) -> Set[Feature]: 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: - features.add(Feature.TRAILING_COMMA) + features.add(feature) if ch.type == syms.argument: for argch in ch.children: if argch.type in STARS: - features.add(Feature.TRAILING_COMMA) + features.add(feature) return features diff --git a/tests/test_black.py b/tests/test_black.py index a3e2ff8..3e0b8a1 100644 --- a/tests/test_black.py +++ b/tests/test_black.py @@ -857,7 +857,11 @@ class BlackTestCase(unittest.TestCase): node = black.lib2to3_parse("def f(*, arg): ...\n") self.assertEqual(black.get_features_used(node), set()) node = black.lib2to3_parse("def f(*, arg,): ...\n") - self.assertEqual(black.get_features_used(node), {Feature.TRAILING_COMMA}) + self.assertEqual(black.get_features_used(node), {Feature.TRAILING_COMMA_IN_DEF}) + node = black.lib2to3_parse("f(*arg,)\n") + self.assertEqual( + black.get_features_used(node), {Feature.TRAILING_COMMA_IN_CALL} + ) node = black.lib2to3_parse("def f(*, arg): f'string'\n") self.assertEqual(black.get_features_used(node), {Feature.F_STRINGS}) node = black.lib2to3_parse("123_456\n") @@ -866,13 +870,14 @@ class BlackTestCase(unittest.TestCase): self.assertEqual(black.get_features_used(node), set()) source, expected = read_data("function") node = black.lib2to3_parse(source) - self.assertEqual( - black.get_features_used(node), {Feature.TRAILING_COMMA, Feature.F_STRINGS} - ) + expected_features = { + Feature.TRAILING_COMMA_IN_CALL, + Feature.TRAILING_COMMA_IN_DEF, + Feature.F_STRINGS, + } + self.assertEqual(black.get_features_used(node), expected_features) node = black.lib2to3_parse(expected) - self.assertEqual( - black.get_features_used(node), {Feature.TRAILING_COMMA, Feature.F_STRINGS} - ) + self.assertEqual(black.get_features_used(node), expected_features) source, expected = read_data("expression") node = black.lib2to3_parse(source) self.assertEqual(black.get_features_used(node), set()) @@ -1524,8 +1529,8 @@ class BlackTestCase(unittest.TestCase): await check("3.6", 200) await check("py3.6", 200) - await check("3.5,3.7", 200) - await check("3.5,py3.7", 200) + await check("3.6,3.7", 200) + await check("3.6,py3.7", 200) await check("2", 204) await check("2.7", 204) -- 2.39.5