Mark Primer projects that will change formatting

[etc/vim.git] / src / black / __init__.py

diff --git a/src/black/__init__.py b/src/black/__init__.py
index 391233ed4485e16dc6798c2d041412dd8c5e1c82..8d0c70f06c7d9561dbc50d6fd48bbbe05d29f4c1 100644 (file)
--- a/src/black/__init__.py
+++ b/src/black/__init__.py
@@ -240,6 +240,7 @@ class Mode:
     target_versions: Set[TargetVersion] = field(default_factory=set)
     line_length: int = DEFAULT_LINE_LENGTH
     string_normalization: bool = True
     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:
     is_pyi: bool = False
 
     def get_cache_key(self) -> str:


@@ -376,6 +377,15 @@ def target_version_option_callback(
     is_flag=True,
     help="Don't normalize string quotes or prefixes.",
 )
     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,
 @click.option(
     "--check",
     is_flag=True,


@@ -485,6 +495,7 @@ def main(
     fast: bool,
     pyi: bool,
     skip_string_normalization: bool,
     fast: bool,
     pyi: bool,
     skip_string_normalization: bool,

+    experimental_string_processing: bool,

     quiet: bool,
     verbose: bool,
     include: str,
     quiet: bool,
     verbose: bool,
     include: str,


@@ -505,6 +516,7 @@ def main(
         line_length=line_length,
         is_pyi=pyi,
         string_normalization=not skip_string_normalization,
         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")
     )
     if config and verbose:
         out(f"Using configuration from {config}.", bold=False, fg="blue")


@@ -940,6 +952,7 @@ def format_str(src_contents: str, *, mode: Mode) -> FileContent:
         ...
 
     A more complex example:
         ...
 
     A more complex example:

+

     >>> print(
     ...   black.format_str(
     ...     "def f(arg:str='')->None: hey",
     >>> print(
     ...   black.format_str(
     ...     "def f(arg:str='')->None: hey",


@@ -984,10 +997,7 @@ def format_str(src_contents: str, *, mode: Mode) -> FileContent:
         before, after = elt.maybe_empty_lines(current_line)
         dst_contents.append(str(empty_line) * before)
         for line in transform_line(
         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)
         ):
             dst_contents.append(str(line))
     return "".join(dst_contents)


@@ -1432,7 +1442,8 @@ class Line:
             )
         if self.inside_brackets or not preformatted:
             self.bracket_tracker.mark(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)
 
         if not self.append_comment(leaf):
             self.leaves.append(leaf)
 


@@ -1484,69 +1495,6 @@ class Line:
             Leaf(token.DOT, ".") for _ in range(3)
         ]
 
             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.)"""
     @property
     def is_def(self) -> bool:
         """Is this a function definition? (Also returns True for async defs.)"""


@@ -1671,42 +1619,29 @@ class Line:
     def contains_multiline_strings(self) -> bool:
         return any(is_multiline_string(leaf) for leaf in self.leaves)
 
     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 pre-existing trailing comma here; and
+        - it's not a one-tuple.
+        """

         if not (
         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 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
+            and not self.leaves[-1].was_checked  # pre-existing

         ):
             return False
 
         ):
             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."""
 
     def append_comment(self, comment: Leaf) -> bool:
         """Add an inline or standalone comment to the line."""


@@ -2649,10 +2584,7 @@ def make_comment(content: str) -> str:
 
 
 def transform_line(
 
 
 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.
 
 ) -> Iterator[Line]:
     """Transform a `line`, potentially splitting it into many lines.
 


@@ -2668,7 +2600,7 @@ def transform_line(
 
     def init_st(ST: Type[StringTransformer]) -> StringTransformer:
         """Initialize StringTransformer"""
 
     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)
 
     string_merge = init_st(StringMerger)
     string_paren_strip = init_st(StringParenStripper)


@@ -2679,23 +2611,27 @@ def transform_line(
     if (
         not line.contains_uncollapsable_type_comments()
         and not line.should_explode
     if (
         not line.contains_uncollapsable_type_comments()
         and not line.should_explode

-        and not line.is_collection_with_optional_trailing_comma

         and (
         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()
         )
             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.
     ):
         # 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]:
     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):
+            for omit in generate_trailers_to_omit(line, mode.line_length):
+                lines = list(
+                    right_hand_split(line, mode.line_length, features, omit=omit)
+                )
+                if is_line_short_enough(lines[0], line_length=mode.line_length):

                     yield from lines
                     return
 
                     yield from lines
                     return
 


@@ -2706,24 +2642,30 @@ def transform_line(
             # See #762 and #781 for the full story.
             yield from right_hand_split(line, line_length=1, features=features)
 
             # 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,
-            ]
+        if mode.experimental_string_processing:
+            if line.inside_brackets:
+                transformers = [
+                    string_merge,
+                    string_paren_strip,
+                    delimiter_split,
+                    standalone_comment_split,
+                    string_split,
+                    string_paren_wrap,
+                    rhs,
+                ]
+            else:
+                transformers = [
+                    string_merge,
+                    string_paren_strip,
+                    string_split,
+                    string_paren_wrap,
+                    rhs,
+                ]

         else:
         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
 
     for transform in transformers:
         # We are accumulating lines in `result` because we might want to abort


@@ -2738,12 +2680,7 @@ def transform_line(
                     )
 
                 result.extend(
                     )
 
                 result.extend(

-                    transform_line(
-                        transformed_line,
-                        line_length=line_length,
-                        normalize_strings=normalize_strings,
-                        features=features,
-                    )
+                    transform_line(transformed_line, mode=mode, features=features)

                 )
         except CannotTransform:
             continue
                 )
         except CannotTransform:
             continue


@@ -4803,10 +4740,8 @@ def right_hand_split(
     tail = bracket_split_build_line(tail_leaves, line, opening_bracket)
     bracket_split_succeeded_or_raise(head, body, tail)
     if (
     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

         # the opening bracket is an optional paren
         # the opening bracket is an optional paren

-        and opening_bracket.type == token.LPAR
+        opening_bracket.type == token.LPAR

         and not opening_bracket.value
         # the closing bracket is an optional paren
         and closing_bracket.type == token.RPAR
         and not opening_bracket.value
         # the closing bracket is an optional paren
         and closing_bracket.type == token.RPAR


@@ -4903,7 +4838,9 @@ def bracket_split_build_line(
                         continue
 
                     if leaves[i].type != token.COMMA:
                         continue
 
                     if leaves[i].type != token.COMMA:

-                        leaves.insert(i + 1, Leaf(token.COMMA, ","))
+                        new_comma = Leaf(token.COMMA, ",")
+                        new_comma.was_checked = True
+                        leaves.insert(i + 1, new_comma)

                     break
 
     # Populate the line
                     break
 
     # Populate the line


@@ -4911,8 +4848,8 @@ def bracket_split_build_line(
         result.append(leaf, preformatted=True)
         for comment_after in original.comments_after(leaf):
             result.append(comment_after, preformatted=True)
         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
 
 
     return result
 
 


@@ -4997,7 +4934,9 @@ def delimiter_split(line: Line, features: Collection[Feature] = ()) -> Iterator[
             and current_line.leaves[-1].type != token.COMMA
             and current_line.leaves[-1].type != STANDALONE_COMMENT
         ):
             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, ",")
+            new_comma.was_checked = True
+            current_line.append(new_comma)

         yield current_line
 
 
         yield current_line
 
 


@@ -5619,24 +5558,60 @@ def ensure_visible(leaf: Leaf) -> None:
         leaf.value = ")"
 
 
         leaf.value = ")"
 
 

-def should_explode(line: Line, opening_bracket: Leaf) -> bool:
+def should_split_body_explode(line: Line, opening_bracket: Leaf) -> bool:

     """Should `line` immediately be split with `delimiter_split()` after RHS?"""
 
     """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}
-        and opening_bracket.value in "[{("
-    ):
+    if not (opening_bracket.parent and opening_bracket.value in "[{("):

         return False
 
         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()
+    pre_existing_trailing_comma = False

     try:
         last_leaf = line.leaves[-1]
     try:
         last_leaf = line.leaves[-1]

-        exclude = {id(last_leaf)} if last_leaf.type == token.COMMA else set()
+        if last_leaf.type == token.COMMA:
+            pre_existing_trailing_comma = not last_leaf.was_checked
+            exclude.add(id(last_leaf))

         max_priority = line.bracket_tracker.max_delimiter_priority(exclude=exclude)
     except (IndexError, ValueError):
         return False
 
         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 (
+        # always explode imports
+        opening_bracket.parent.type in {syms.atom, syms.import_from}
+        or pre_existing_trailing_comma
+    )
+
+
+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."""
+    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]:
 
 
 def get_features_used(node: Node) -> Set[Feature]: