Add link to the pyproject.toml for setting up pre-commit hook (#885)

[etc/vim.git] / black.py

diff --git a/black.py b/black.py
index c96d205deebff910003f7b70db82ab1d4f97be06..635eba207cd0c2a695cab27d68326216a90325f5 100644 (file)
--- a/black.py
+++ b/black.py
@@ -16,6 +16,7 @@ import signal
 import sys
 import tempfile
 import tokenize
 import sys
 import tempfile
 import tokenize

+import traceback

 from typing import (
     Any,
     Callable,
 from typing import (
     Any,
     Callable,


@@ -136,19 +137,28 @@ class Feature(Enum):
     NUMERIC_UNDERSCORES = 3
     TRAILING_COMMA_IN_CALL = 4
     TRAILING_COMMA_IN_DEF = 5
     NUMERIC_UNDERSCORES = 3
     TRAILING_COMMA_IN_CALL = 4
     TRAILING_COMMA_IN_DEF = 5

+    # The following two feature-flags are mutually exclusive, and exactly one should be
+    # set for every version of python.
+    ASYNC_IDENTIFIERS = 6
+    ASYNC_KEYWORDS = 7

 
 
 VERSION_TO_FEATURES: Dict[TargetVersion, Set[Feature]] = {
 
 
 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.PY27: {Feature.ASYNC_IDENTIFIERS},
+    TargetVersion.PY33: {Feature.UNICODE_LITERALS, Feature.ASYNC_IDENTIFIERS},
+    TargetVersion.PY34: {Feature.UNICODE_LITERALS, Feature.ASYNC_IDENTIFIERS},
+    TargetVersion.PY35: {
+        Feature.UNICODE_LITERALS,
+        Feature.TRAILING_COMMA_IN_CALL,
+        Feature.ASYNC_IDENTIFIERS,
+    },

     TargetVersion.PY36: {
         Feature.UNICODE_LITERALS,
         Feature.F_STRINGS,
         Feature.NUMERIC_UNDERSCORES,
         Feature.TRAILING_COMMA_IN_CALL,
         Feature.TRAILING_COMMA_IN_DEF,
     TargetVersion.PY36: {
         Feature.UNICODE_LITERALS,
         Feature.F_STRINGS,
         Feature.NUMERIC_UNDERSCORES,
         Feature.TRAILING_COMMA_IN_CALL,
         Feature.TRAILING_COMMA_IN_DEF,

+        Feature.ASYNC_IDENTIFIERS,

     },
     TargetVersion.PY37: {
         Feature.UNICODE_LITERALS,
     },
     TargetVersion.PY37: {
         Feature.UNICODE_LITERALS,


@@ -156,6 +166,7 @@ VERSION_TO_FEATURES: Dict[TargetVersion, Set[Feature]] = {
         Feature.NUMERIC_UNDERSCORES,
         Feature.TRAILING_COMMA_IN_CALL,
         Feature.TRAILING_COMMA_IN_DEF,
         Feature.NUMERIC_UNDERSCORES,
         Feature.TRAILING_COMMA_IN_CALL,
         Feature.TRAILING_COMMA_IN_DEF,

+        Feature.ASYNC_KEYWORDS,

     },
     TargetVersion.PY38: {
         Feature.UNICODE_LITERALS,
     },
     TargetVersion.PY38: {
         Feature.UNICODE_LITERALS,


@@ -163,6 +174,7 @@ VERSION_TO_FEATURES: Dict[TargetVersion, Set[Feature]] = {
         Feature.NUMERIC_UNDERSCORES,
         Feature.TRAILING_COMMA_IN_CALL,
         Feature.TRAILING_COMMA_IN_DEF,
         Feature.NUMERIC_UNDERSCORES,
         Feature.TRAILING_COMMA_IN_CALL,
         Feature.TRAILING_COMMA_IN_DEF,

+        Feature.ASYNC_KEYWORDS,

     },
 }
 
     },
 }
 


@@ -325,7 +337,7 @@ def read_pyproject_toml(
     "--quiet",
     is_flag=True,
     help=(
     "--quiet",
     is_flag=True,
     help=(

-        "Don't emit non-error messages to stderr. Errors are still emitted, "
+        "Don't emit non-error messages to stderr. Errors are still emitted; "

         "silence those with 2>/dev/null."
     ),
 )
         "silence those with 2>/dev/null."
     ),
 )


@@ -446,8 +458,7 @@ def main(
         )
 
     if verbose or not quiet:
         )
 
     if verbose or not quiet:

-        bang = "💥 💔 💥" if report.return_code else "✨ 🍰 ✨"
-        out(f"All done! {bang}")
+        out("Oh no! 💥 💔 💥" if report.return_code else "All done! ✨ 🍰 ✨")

         click.secho(str(report), err=True)
     ctx.exit(report.return_code)
 
         click.secho(str(report), err=True)
     ctx.exit(report.return_code)
 


@@ -457,8 +468,7 @@ def reformat_one(
 ) -> None:
     """Reformat a single file under `src` without spawning child processes.
 
 ) -> None:
     """Reformat a single file under `src` without spawning child processes.
 

-    If `quiet` is True, non-error messages are not output. `line_length`,
-    `write_back`, `fast` and `pyi` options are passed to
+    `fast`, `write_back`, and `mode` options are passed to

     :func:`format_file_in_place` or :func:`format_stdin_to_stdout`.
     """
     try:
     :func:`format_file_in_place` or :func:`format_stdin_to_stdout`.
     """
     try:


@@ -598,7 +608,7 @@ def format_file_in_place(
 
     If `write_back` is DIFF, write a diff to stdout. If it is YES, write reformatted
     code to the file.
 
     If `write_back` is DIFF, write a diff to stdout. If it is YES, write reformatted
     code to the file.

-    `line_length` and `fast` options are passed to :func:`format_file_contents`.
+    `mode` and `fast` options are passed to :func:`format_file_contents`.

     """
     if src.suffix == ".pyi":
         mode = evolve(mode, is_pyi=True)
     """
     if src.suffix == ".pyi":
         mode = evolve(mode, is_pyi=True)


@@ -676,7 +686,7 @@ def format_file_contents(
 
     If `fast` is False, additionally confirm that the reformatted code is
     valid by calling :func:`assert_equivalent` and :func:`assert_stable` on it.
 
     If `fast` is False, additionally confirm that the reformatted code is
     valid by calling :func:`assert_equivalent` and :func:`assert_stable` on it.

-    `line_length` is passed to :func:`format_str`.
+    `mode` is passed to :func:`format_str`.

     """
     if src_contents.strip() == "":
         raise NothingChanged
     """
     if src_contents.strip() == "":
         raise NothingChanged


@@ -694,10 +704,11 @@ def format_file_contents(
 def format_str(src_contents: str, *, mode: FileMode) -> FileContent:
     """Reformat a string and return new contents.
 
 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.
+    `mode` determines formatting options, such as how many characters per line are
+    allowed.

     """
     src_node = lib2to3_parse(src_contents.lstrip(), mode.target_versions)
     """
     src_node = lib2to3_parse(src_contents.lstrip(), mode.target_versions)

-    dst_contents = ""
+    dst_contents = []

     future_imports = get_future_imports(src_node)
     if mode.target_versions:
         versions = mode.target_versions
     future_imports = get_future_imports(src_node)
     if mode.target_versions:
         versions = mode.target_versions


@@ -720,15 +731,15 @@ def format_str(src_contents: str, *, mode: FileMode) -> FileContent:
     }
     for current_line in lines.visit(src_node):
         for _ in range(after):
     }
     for current_line in lines.visit(src_node):
         for _ in range(after):

-            dst_contents += str(empty_line)
+            dst_contents.append(str(empty_line))

         before, after = elt.maybe_empty_lines(current_line)
         for _ in range(before):
         before, after = elt.maybe_empty_lines(current_line)
         for _ in range(before):

-            dst_contents += str(empty_line)
+            dst_contents.append(str(empty_line))

         for line in split_line(
             current_line, line_length=mode.line_length, features=split_line_features
         ):
         for line in split_line(
             current_line, line_length=mode.line_length, features=split_line_features
         ):

-            dst_contents += str(line)
-    return dst_contents
+            dst_contents.append(str(line))
+    return "".join(dst_contents)

 
 
 def decode_bytes(src: bytes) -> Tuple[FileContent, Encoding, NewLine]:
 
 
 def decode_bytes(src: bytes) -> Tuple[FileContent, Encoding, NewLine]:


@@ -752,16 +763,38 @@ def get_grammars(target_versions: Set[TargetVersion]) -> List[Grammar]:
     if not target_versions:
         # No target_version specified, so try all grammars.
         return [
     if not target_versions:
         # No target_version specified, so try all grammars.
         return [

+            # Python 3.7+
+            pygram.python_grammar_no_print_statement_no_exec_statement_async_keywords,
+            # Python 3.0-3.6

             pygram.python_grammar_no_print_statement_no_exec_statement,
             pygram.python_grammar_no_print_statement_no_exec_statement,

+            # Python 2.7 with future print_function import

             pygram.python_grammar_no_print_statement,
             pygram.python_grammar_no_print_statement,

+            # Python 2.7

             pygram.python_grammar,
         ]
     elif all(version.is_python2() for version in target_versions):
         # Python 2-only code, so try Python 2 grammars.
             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]
+        return [
+            # Python 2.7 with future print_function import
+            pygram.python_grammar_no_print_statement,
+            # Python 2.7
+            pygram.python_grammar,
+        ]

     else:
         # Python 3-compatible code, so only try Python 3 grammar.
     else:
         # Python 3-compatible code, so only try Python 3 grammar.

-        return [pygram.python_grammar_no_print_statement_no_exec_statement]
+        grammars = []
+        # If we have to parse both, try to parse async as a keyword first
+        if not supports_feature(target_versions, Feature.ASYNC_IDENTIFIERS):
+            # Python 3.7+
+            grammars.append(
+                pygram.python_grammar_no_print_statement_no_exec_statement_async_keywords  # noqa: B950
+            )
+        if not supports_feature(target_versions, Feature.ASYNC_KEYWORDS):
+            # Python 3.0-3.6
+            grammars.append(pygram.python_grammar_no_print_statement_no_exec_statement)
+        # At least one of the above branches must have been taken, because every Python
+        # version has exactly one of the two 'ASYNC_*' flags
+        return grammars

 
 
 def lib2to3_parse(src_txt: str, target_versions: Iterable[TargetVersion] = ()) -> Node:
 
 
 def lib2to3_parse(src_txt: str, target_versions: Iterable[TargetVersion] = ()) -> Node:


@@ -1028,7 +1061,7 @@ class BracketTracker:
         """Return True if there is an yet unmatched open bracket on the line."""
         return bool(self.bracket_match)
 
         """Return True if there is an yet unmatched open bracket on the line."""
         return bool(self.bracket_match)
 

-    def max_delimiter_priority(self, exclude: Iterable[LeafID] = ()) -> int:
+    def max_delimiter_priority(self, exclude: Iterable[LeafID] = ()) -> Priority:

         """Return the highest priority of a delimiter found on the line.
 
         Values are consistent with what `is_split_*_delimiter()` return.
         """Return the highest priority of a delimiter found on the line.
 
         Values are consistent with what `is_split_*_delimiter()` return.


@@ -1036,7 +1069,7 @@ class BracketTracker:
         """
         return max(v for k, v in self.delimiters.items() if k not in exclude)
 
         """
         return max(v for k, v in self.delimiters.items() if k not in exclude)
 

-    def delimiter_count_with_priority(self, priority: int = 0) -> int:
+    def delimiter_count_with_priority(self, priority: Priority = 0) -> int:

         """Return the number of delimiters with the given `priority`.
 
         If no `priority` is passed, defaults to max priority on the line.
         """Return the number of delimiters with the given `priority`.
 
         If no `priority` is passed, defaults to max priority on the line.


@@ -1569,6 +1602,26 @@ class LineGenerator(Visitor[Line]):
                 self.current_line.append(node)
         yield from super().visit_default(node)
 
                 self.current_line.append(node)
         yield from super().visit_default(node)
 

+    def visit_atom(self, node: Node) -> Iterator[Line]:
+        # Always make parentheses invisible around a single node, because it should
+        # not be needed (except in the case of yield, where removing the parentheses
+        # produces a SyntaxError).
+        if (
+            len(node.children) == 3
+            and isinstance(node.children[0], Leaf)
+            and node.children[0].type == token.LPAR
+            and isinstance(node.children[2], Leaf)
+            and node.children[2].type == token.RPAR
+            and isinstance(node.children[1], Leaf)
+            and not (
+                node.children[1].type == token.NAME
+                and node.children[1].value == "yield"
+            )
+        ):
+            node.children[0].value = ""
+            node.children[2].value = ""
+        yield from super().visit_default(node)
+

     def visit_INDENT(self, node: Node) -> Iterator[Line]:
         """Increase indentation level, maybe yield a line."""
         # In blib2to3 INDENT never holds comments.
     def visit_INDENT(self, node: Node) -> Iterator[Line]:
         """Increase indentation level, maybe yield a line."""
         # In blib2to3 INDENT never holds comments.


@@ -1982,7 +2035,7 @@ def container_of(leaf: Leaf) -> LN:
     return container
 
 
     return container
 
 

-def is_split_after_delimiter(leaf: Leaf, previous: Optional[Leaf] = None) -> int:
+def is_split_after_delimiter(leaf: Leaf, previous: Optional[Leaf] = None) -> Priority:

     """Return the priority of the `leaf` delimiter, given a line break after it.
 
     The delimiter priorities returned here are from those delimiters that would
     """Return the priority of the `leaf` delimiter, given a line break after it.
 
     The delimiter priorities returned here are from those delimiters that would


@@ -1996,7 +2049,7 @@ def is_split_after_delimiter(leaf: Leaf, previous: Optional[Leaf] = None) -> int
     return 0
 
 
     return 0
 
 

-def is_split_before_delimiter(leaf: Leaf, previous: Optional[Leaf] = None) -> int:
+def is_split_before_delimiter(leaf: Leaf, previous: Optional[Leaf] = None) -> Priority:

     """Return the priority of the `leaf` delimiter, given a line break before it.
 
     The delimiter priorities returned here are from those delimiters that would
     """Return the priority of the `leaf` delimiter, given a line break before it.
 
     The delimiter priorities returned here are from those delimiters that would


@@ -2676,7 +2729,15 @@ def normalize_string_quotes(leaf: Leaf) -> None:
         new_body = sub_twice(escaped_orig_quote, rf"\1\2{orig_quote}", new_body)
         new_body = sub_twice(unescaped_new_quote, rf"\1\\{new_quote}", new_body)
     if "f" in prefix.casefold():
         new_body = sub_twice(escaped_orig_quote, rf"\1\2{orig_quote}", new_body)
         new_body = sub_twice(unescaped_new_quote, rf"\1\\{new_quote}", new_body)
     if "f" in prefix.casefold():

-        matches = re.findall(r"[^{]\{(.*?)\}[^}]", new_body)
+        matches = re.findall(
+            r"""
+            (?:[^{]|^)\{  # start of the string or a non-{ followed by a single {
+                ([^{].*?)  # contents of the brackets except if begins with {{
+            \}(?:[^}]|$)  # A } followed by end of the string or a non-}
+            """,
+            new_body,
+            re.VERBOSE,
+        )

         for m in matches:
             if "\\" in str(m):
                 # Do not introduce backslashes in interpolated expressions
         for m in matches:
             if "\\" in str(m):
                 # Do not introduce backslashes in interpolated expressions


@@ -2743,7 +2804,7 @@ def format_float_or_int_string(text: str) -> str:
 def normalize_invisible_parens(node: Node, parens_after: Set[str]) -> None:
     """Make existing optional parentheses invisible or create new ones.
 
 def normalize_invisible_parens(node: Node, parens_after: Set[str]) -> None:
     """Make existing optional parentheses invisible or create new ones.
 

-    `parens_after` is a set of string leaf values immeditely after which parens
+    `parens_after` is a set of string leaf values immediately after which parens

     should be put.
 
     Standardizes on visible parentheses for single-element tuples, and keeps
     should be put.
 
     Standardizes on visible parentheses for single-element tuples, and keeps


@@ -3021,7 +3082,7 @@ def is_stub_body(node: LN) -> bool:
     )
 
 
     )
 
 

-def max_delimiter_priority_in_atom(node: LN) -> int:
+def max_delimiter_priority_in_atom(node: LN) -> Priority:

     """Return maximum delimiter priority inside `node`.
 
     This is specific to atoms with contents contained in a pair of parentheses.
     """Return maximum delimiter priority inside `node`.
 
     This is specific to atoms with contents contained in a pair of parentheses.


@@ -3394,8 +3455,6 @@ def parse_ast(src: str) -> Union[ast3.AST, ast27.AST]:
 def assert_equivalent(src: str, dst: str) -> None:
     """Raise AssertionError if `src` and `dst` aren't equivalent."""
 
 def assert_equivalent(src: str, dst: str) -> None:
     """Raise AssertionError if `src` and `dst` aren't equivalent."""
 

-    import traceback
-

     def _v(node: Union[ast3.AST, ast27.AST], depth: int = 0) -> Iterator[str]:
         """Simple visitor generating strings to compare ASTs by content."""
         yield f"{'  ' * depth}{node.__class__.__name__}("
     def _v(node: Union[ast3.AST, ast27.AST], depth: int = 0) -> Iterator[str]:
         """Simple visitor generating strings to compare ASTs by content."""
         yield f"{'  ' * depth}{node.__class__.__name__}("


@@ -3486,8 +3545,6 @@ def assert_stable(src: str, dst: str, mode: FileMode) -> None:
 
 def dump_to_file(*output: str) -> str:
     """Dump `output` to a temporary file. Return path to the file."""
 
 def dump_to_file(*output: str) -> str:
     """Dump `output` to a temporary file. Return path to the file."""

-    import tempfile
-

     with tempfile.NamedTemporaryFile(
         mode="w", prefix="blk_", suffix=".log", delete=False, encoding="utf8"
     ) as f:
     with tempfile.NamedTemporaryFile(
         mode="w", prefix="blk_", suffix=".log", delete=False, encoding="utf8"
     ) as f:


@@ -3585,7 +3642,6 @@ def enumerate_with_length(
         if "\n" in leaf.value:
             return  # Multiline strings, we can't continue.
 
         if "\n" in leaf.value:
             return  # Multiline strings, we can't continue.
 

-        comment: Optional[Leaf]

         for comment in line.comments_after(leaf):
             length += len(comment.value)
 
         for comment in line.comments_after(leaf):
             length += len(comment.value)