Add integration for pre-commit.com (#104)

[etc/vim.git] / black.py

diff --git a/black.py b/black.py
index dc03e0a9b3a324cb266eae50143bf7a97dcb72d9..01390b3236d30f1a9ad5416f40d7322297f16032 100644 (file)
--- a/black.py
+++ b/black.py
@@ -3,15 +3,18 @@
 import asyncio
 from asyncio.base_events import BaseEventLoop
 from concurrent.futures import Executor, ProcessPoolExecutor
 import asyncio
 from asyncio.base_events import BaseEventLoop
 from concurrent.futures import Executor, ProcessPoolExecutor

+from enum import Enum

 from functools import partial, wraps
 import keyword
 import logging
 from functools import partial, wraps
 import keyword
 import logging

+from multiprocessing import Manager

 import os
 from pathlib import Path
 import tokenize
 import signal
 import sys
 from typing import (
 import os
 from pathlib import Path
 import tokenize
 import signal
 import sys
 from typing import (

+    Any,

     Callable,
     Dict,
     Generic,
     Callable,
     Dict,
     Generic,


@@ -35,7 +38,7 @@ from blib2to3 import pygram, pytree
 from blib2to3.pgen2 import driver, token
 from blib2to3.pgen2.parse import ParseError
 
 from blib2to3.pgen2 import driver, token
 from blib2to3.pgen2.parse import ParseError
 

-__version__ = "18.3a4"
+__version__ = "18.4a0"

 DEFAULT_LINE_LENGTH = 88
 # types
 syms = pygram.python_symbols
 DEFAULT_LINE_LENGTH = 88
 # types
 syms = pygram.python_symbols


@@ -92,6 +95,12 @@ class FormatOff(FormatError):
     """Found a comment like `# fmt: off` in the file."""
 
 
     """Found a comment like `# fmt: off` in the file."""
 
 

+class WriteBack(Enum):
+    NO = 0
+    YES = 1
+    DIFF = 2
+
+

 @click.command()
 @click.option(
     "-l",
 @click.command()
 @click.option(
     "-l",


@@ -105,16 +114,30 @@ class FormatOff(FormatError):
     "--check",
     is_flag=True,
     help=(
     "--check",
     is_flag=True,
     help=(

-        "Don't write back the files, just return the status.  Return code 0 "
+        "Don't write the files back, just return the status.  Return code 0 "

         "means nothing would change.  Return code 1 means some files would be "
         "reformatted.  Return code 123 means there was an internal error."
     ),
 )
         "means nothing would change.  Return code 1 means some files would be "
         "reformatted.  Return code 123 means there was an internal error."
     ),
 )

+@click.option(
+    "--diff",
+    is_flag=True,
+    help="Don't write the files back, just output a diff for each file on stdout.",
+)

 @click.option(
     "--fast/--safe",
     is_flag=True,
     help="If --fast given, skip temporary sanity checks. [default: --safe]",
 )
 @click.option(
     "--fast/--safe",
     is_flag=True,
     help="If --fast given, skip temporary sanity checks. [default: --safe]",
 )

+@click.option(
+    "-q",
+    "--quiet",
+    is_flag=True,
+    help=(
+        "Don't emit non-error messages to stderr. Errors are still emitted, "
+        "silence those with 2>/dev/null."
+    ),
+)

 @click.version_option(version=__version__)
 @click.argument(
     "src",
 @click.version_option(version=__version__)
 @click.argument(
     "src",


@@ -125,7 +148,13 @@ class FormatOff(FormatError):
 )
 @click.pass_context
 def main(
 )
 @click.pass_context
 def main(

-    ctx: click.Context, line_length: int, check: bool, fast: bool, src: List[str]
+    ctx: click.Context,
+    line_length: int,
+    check: bool,
+    diff: bool,
+    fast: bool,
+    quiet: bool,
+    src: List[str],

 ) -> None:
     """The uncompromising code formatter."""
     sources: List[Path] = []
 ) -> None:
     """The uncompromising code formatter."""
     sources: List[Path] = []


@@ -140,19 +169,30 @@ def main(
             sources.append(Path("-"))
         else:
             err(f"invalid path: {s}")
             sources.append(Path("-"))
         else:
             err(f"invalid path: {s}")

+    if check and diff:
+        exc = click.ClickException("Options --check and --diff are mutually exclusive")
+        exc.exit_code = 2
+        raise exc
+
+    if check:
+        write_back = WriteBack.NO
+    elif diff:
+        write_back = WriteBack.DIFF
+    else:
+        write_back = WriteBack.YES

     if len(sources) == 0:
         ctx.exit(0)
     elif len(sources) == 1:
         p = sources[0]
     if len(sources) == 0:
         ctx.exit(0)
     elif len(sources) == 1:
         p = sources[0]

-        report = Report(check=check)
+        report = Report(check=check, quiet=quiet)

         try:
             if not p.is_file() and str(p) == "-":
                 changed = format_stdin_to_stdout(
         try:
             if not p.is_file() and str(p) == "-":
                 changed = format_stdin_to_stdout(

-                    line_length=line_length, fast=fast, write_back=not check
+                    line_length=line_length, fast=fast, write_back=write_back

                 )
             else:
                 changed = format_file_in_place(
                 )
             else:
                 changed = format_file_in_place(

-                    p, line_length=line_length, fast=fast, write_back=not check
+                    p, line_length=line_length, fast=fast, write_back=write_back

                 )
             report.done(p, changed)
         except Exception as exc:
                 )
             report.done(p, changed)
         except Exception as exc:


@@ -165,7 +205,7 @@ def main(
         try:
             return_code = loop.run_until_complete(
                 schedule_formatting(
         try:
             return_code = loop.run_until_complete(
                 schedule_formatting(

-                    sources, line_length, not check, fast, loop, executor
+                    sources, line_length, write_back, fast, quiet, loop, executor

                 )
             )
         finally:
                 )
             )
         finally:


@@ -176,8 +216,9 @@ def main(
 async def schedule_formatting(
     sources: List[Path],
     line_length: int,
 async def schedule_formatting(
     sources: List[Path],
     line_length: int,

-    write_back: bool,
+    write_back: WriteBack,

     fast: bool,
     fast: bool,

+    quiet: bool,

     loop: BaseEventLoop,
     executor: Executor,
 ) -> int:
     loop: BaseEventLoop,
     executor: Executor,
 ) -> int:


@@ -188,9 +229,15 @@ async def schedule_formatting(
     `line_length`, `write_back`, and `fast` options are passed to
     :func:`format_file_in_place`.
     """
     `line_length`, `write_back`, and `fast` options are passed to
     :func:`format_file_in_place`.
     """

+    lock = None
+    if write_back == WriteBack.DIFF:
+        # For diff output, we need locks to ensure we don't interleave output
+        # from different processes.
+        manager = Manager()
+        lock = manager.Lock()

     tasks = {
         src: loop.run_in_executor(
     tasks = {
         src: loop.run_in_executor(

-            executor, format_file_in_place, src, line_length, fast, write_back
+            executor, format_file_in_place, src, line_length, fast, write_back, lock

         )
         for src in sources
     }
         )
         for src in sources
     }


@@ -199,7 +246,7 @@ async def schedule_formatting(
     loop.add_signal_handler(signal.SIGTERM, cancel, _task_values)
     await asyncio.wait(tasks.values())
     cancelled = []
     loop.add_signal_handler(signal.SIGTERM, cancel, _task_values)
     await asyncio.wait(tasks.values())
     cancelled = []

-    report = Report(check=not write_back)
+    report = Report(check=write_back is WriteBack.NO, quiet=quiet)

     for src, task in tasks.items():
         if not task.done():
             report.failed(src, "timed out, cancelling")
     for src, task in tasks.items():
         if not task.done():
             report.failed(src, "timed out, cancelling")


@@ -213,14 +260,19 @@ async def schedule_formatting(
             report.done(src, task.result())
     if cancelled:
         await asyncio.gather(*cancelled, loop=loop, return_exceptions=True)
             report.done(src, task.result())
     if cancelled:
         await asyncio.gather(*cancelled, loop=loop, return_exceptions=True)

-    else:
+    elif not quiet:

         out("All done! ✨ 🍰 ✨")
         out("All done! ✨ 🍰 ✨")

-    click.echo(str(report))
+    if not quiet:
+        click.echo(str(report))

     return report.return_code
 
 
 def format_file_in_place(
     return report.return_code
 
 
 def format_file_in_place(

-    src: Path, line_length: int, fast: bool, write_back: bool = False
+    src: Path,
+    line_length: int,
+    fast: bool,
+    write_back: WriteBack = WriteBack.NO,
+    lock: Any = None,  # multiprocessing.Manager().Lock() is some crazy proxy

 ) -> bool:
     """Format file under `src` path. Return True if changed.
 
 ) -> bool:
     """Format file under `src` path. Return True if changed.
 


@@ -230,37 +282,53 @@ def format_file_in_place(
     with tokenize.open(src) as src_buffer:
         src_contents = src_buffer.read()
     try:
     with tokenize.open(src) as src_buffer:
         src_contents = src_buffer.read()
     try:

-        contents = format_file_contents(
+        dst_contents = format_file_contents(

             src_contents, line_length=line_length, fast=fast
         )
     except NothingChanged:
         return False
 
             src_contents, line_length=line_length, fast=fast
         )
     except NothingChanged:
         return False
 

-    if write_back:
+    if write_back == write_back.YES:

         with open(src, "w", encoding=src_buffer.encoding) as f:
         with open(src, "w", encoding=src_buffer.encoding) as f:

-            f.write(contents)
+            f.write(dst_contents)
+    elif write_back == write_back.DIFF:
+        src_name = f"{src.name}  (original)"
+        dst_name = f"{src.name}  (formatted)"
+        diff_contents = diff(src_contents, dst_contents, src_name, dst_name)
+        if lock:
+            lock.acquire()
+        try:
+            sys.stdout.write(diff_contents)
+        finally:
+            if lock:
+                lock.release()

     return True
 
 
 def format_stdin_to_stdout(
     return True
 
 
 def format_stdin_to_stdout(

-    line_length: int, fast: bool, write_back: bool = False
+    line_length: int, fast: bool, write_back: WriteBack = WriteBack.NO

 ) -> bool:
     """Format file on stdin. Return True if changed.
 
     If `write_back` is True, write reformatted code back to stdout.
     `line_length` and `fast` arguments are passed to :func:`format_file_contents`.
     """
 ) -> bool:
     """Format file on stdin. Return True if changed.
 
     If `write_back` is True, write reformatted code back to stdout.
     `line_length` and `fast` arguments are passed to :func:`format_file_contents`.
     """

-    contents = sys.stdin.read()
+    src = sys.stdin.read()

     try:
     try:

-        contents = format_file_contents(contents, line_length=line_length, fast=fast)
+        dst = format_file_contents(src, line_length=line_length, fast=fast)

         return True
 
     except NothingChanged:
         return True
 
     except NothingChanged:

+        dst = src

         return False
 
     finally:
         return False
 
     finally:

-        if write_back:
-            sys.stdout.write(contents)
+        if write_back == WriteBack.YES:
+            sys.stdout.write(dst)
+        elif write_back == WriteBack.DIFF:
+            src_name = "<stdin>  (original)"
+            dst_name = "<stdin>  (formatted)"
+            sys.stdout.write(diff(src, dst, src_name, dst_name))

 
 
 def format_file_contents(
 
 
 def format_file_contents(


@@ -451,6 +519,7 @@ MATH_OPERATORS = {
     token.DOUBLESTAR,
     token.DOUBLESLASH,
 }
     token.DOUBLESTAR,
     token.DOUBLESLASH,
 }

+VARARGS = {token.STAR, token.DOUBLESTAR}

 COMPREHENSION_PRIORITY = 20
 COMMA_PRIORITY = 10
 LOGIC_PRIORITY = 5
 COMPREHENSION_PRIORITY = 20
 COMMA_PRIORITY = 10
 LOGIC_PRIORITY = 5


@@ -492,32 +561,12 @@ class BracketTracker:
             leaf.opening_bracket = opening_bracket
         leaf.bracket_depth = self.depth
         if self.depth == 0:
             leaf.opening_bracket = opening_bracket
         leaf.bracket_depth = self.depth
         if self.depth == 0:

-            delim = is_delimiter(leaf)
-            if delim:
-                self.delimiters[id(leaf)] = delim
-            elif self.previous is not None:
-                if leaf.type == token.STRING and self.previous.type == token.STRING:
-                    self.delimiters[id(self.previous)] = STRING_PRIORITY
-                elif (
-                    leaf.type == token.NAME
-                    and leaf.value == "for"
-                    and leaf.parent
-                    and leaf.parent.type in {syms.comp_for, syms.old_comp_for}
-                ):
-                    self.delimiters[id(self.previous)] = COMPREHENSION_PRIORITY
-                elif (
-                    leaf.type == token.NAME
-                    and leaf.value == "if"
-                    and leaf.parent
-                    and leaf.parent.type in {syms.comp_if, syms.old_comp_if}
-                ):
-                    self.delimiters[id(self.previous)] = COMPREHENSION_PRIORITY
-                elif (
-                    leaf.type == token.NAME
-                    and leaf.value in LOGIC_OPERATORS
-                    and leaf.parent
-                ):
-                    self.delimiters[id(self.previous)] = LOGIC_PRIORITY
+            after_delim = is_split_after_delimiter(leaf, self.previous)
+            before_delim = is_split_before_delimiter(leaf, self.previous)
+            if after_delim > before_delim:
+                self.delimiters[id(leaf)] = after_delim
+            elif before_delim > after_delim and self.previous is not None:
+                self.delimiters[id(self.previous)] = before_delim

         if leaf.type in OPENING_BRACKETS:
             self.bracket_match[self.depth, BRACKET[leaf.type]] = leaf
             self.depth += 1
         if leaf.type in OPENING_BRACKETS:
             self.bracket_match[self.depth, BRACKET[leaf.type]] = leaf
             self.depth += 1


@@ -1097,6 +1146,10 @@ class LineGenerator(Visitor[Line]):
                 yield from self.line()
                 yield from self.visit(node)
 
                 yield from self.line()
                 yield from self.visit(node)
 

+            if node.type == token.ENDMARKER:
+                # somebody decided not to put a final `# fmt: on`
+                yield from self.line()
+

     def __attrs_post_init__(self) -> None:
         """You are in a twisty little maze of passages."""
         v = self.visit_stmt
     def __attrs_post_init__(self) -> None:
         """You are in a twisty little maze of passages."""
         v = self.visit_stmt


@@ -1374,17 +1427,35 @@ def preceding_leaf(node: Optional[LN]) -> Optional[Leaf]:
     return None
 
 
     return None
 
 

-def is_delimiter(leaf: Leaf) -> int:
-    """Return the priority of the `leaf` delimiter. Return 0 if not delimiter.
+def is_split_after_delimiter(leaf: Leaf, previous: Leaf = None) -> int:
+    """Return the priority of the `leaf` delimiter, given a line break after it.
+
+    The delimiter priorities returned here are from those delimiters that would
+    cause a line break after themselves.

 
     Higher numbers are higher priority.
     """
     if leaf.type == token.COMMA:
         return COMMA_PRIORITY
 
 
     Higher numbers are higher priority.
     """
     if leaf.type == token.COMMA:
         return COMMA_PRIORITY
 

-    if leaf.type in COMPARATORS:
-        return COMPARATOR_PRIORITY
+    if (
+        leaf.type in VARARGS
+        and leaf.parent
+        and leaf.parent.type in {syms.argument, syms.typedargslist}
+    ):
+        return MATH_PRIORITY
+
+    return 0
+

 
 

+def is_split_before_delimiter(leaf: Leaf, previous: Leaf = None) -> int:
+    """Return the priority of the `leaf` delimiter, given a line before after it.
+
+    The delimiter priorities returned here are from those delimiters that would
+    cause a line break before themselves.
+
+    Higher numbers are higher priority.
+    """

     if (
         leaf.type in MATH_OPERATORS
         and leaf.parent
     if (
         leaf.type in MATH_OPERATORS
         and leaf.parent


@@ -1392,9 +1463,49 @@ def is_delimiter(leaf: Leaf) -> int:
     ):
         return MATH_PRIORITY
 
     ):
         return MATH_PRIORITY
 

+    if leaf.type in COMPARATORS:
+        return COMPARATOR_PRIORITY
+
+    if (
+        leaf.type == token.STRING
+        and previous is not None
+        and previous.type == token.STRING
+    ):
+        return STRING_PRIORITY
+
+    if (
+        leaf.type == token.NAME
+        and leaf.value == "for"
+        and leaf.parent
+        and leaf.parent.type in {syms.comp_for, syms.old_comp_for}
+    ):
+        return COMPREHENSION_PRIORITY
+
+    if (
+        leaf.type == token.NAME
+        and leaf.value == "if"
+        and leaf.parent
+        and leaf.parent.type in {syms.comp_if, syms.old_comp_if}
+    ):
+        return COMPREHENSION_PRIORITY
+
+    if leaf.type == token.NAME and leaf.value in LOGIC_OPERATORS and leaf.parent:
+        return LOGIC_PRIORITY
+

     return 0
 
 
     return 0
 
 

+def is_delimiter(leaf: Leaf, previous: Leaf = None) -> int:
+    """Return the priority of the `leaf` delimiter. Return 0 if not delimiter.
+
+    Higher numbers are higher priority.
+    """
+    return max(
+        is_split_before_delimiter(leaf, previous),
+        is_split_after_delimiter(leaf, previous),
+    )
+
+

 def generate_comments(leaf: Leaf) -> Iterator[Leaf]:
     """Clean the prefix of the `leaf` and generate comments from it, if any.
 
 def generate_comments(leaf: Leaf) -> Iterator[Leaf]:
     """Clean the prefix of the `leaf` and generate comments from it, if any.
 


@@ -1442,7 +1553,12 @@ def generate_comments(leaf: Leaf) -> Iterator[Leaf]:
             raise FormatOn(consumed)
 
         if comment in {"# fmt: off", "# yapf: disable"}:
             raise FormatOn(consumed)
 
         if comment in {"# fmt: off", "# yapf: disable"}:

-            raise FormatOff(consumed)
+            if comment_type == STANDALONE_COMMENT:
+                raise FormatOff(consumed)
+
+            prev = preceding_leaf(leaf)
+            if not prev or prev.type in WHITESPACE:  # standalone comment in disguise
+                raise FormatOff(consumed)

 
         nlines = 0
 
 
         nlines = 0
 


@@ -1701,9 +1817,10 @@ def delimiter_split(line: Line, py36: bool = False) -> Iterator[Line]:
             current_line = Line(depth=line.depth, inside_brackets=line.inside_brackets)
     if current_line:
         if (
             current_line = Line(depth=line.depth, inside_brackets=line.inside_brackets)
     if current_line:
         if (

-            delimiter_priority == COMMA_PRIORITY
+            trailing_comma_safe
+            and delimiter_priority == COMMA_PRIORITY

             and current_line.leaves[-1].type != token.COMMA
             and current_line.leaves[-1].type != token.COMMA

-            and trailing_comma_safe
+            and current_line.leaves[-1].type != STANDALONE_COMMENT

         ):
             current_line.append(Leaf(token.COMMA, ","))
         yield current_line
         ):
             current_line.append(Leaf(token.COMMA, ","))
         yield current_line


@@ -1776,6 +1893,13 @@ def normalize_prefix(leaf: Leaf, *, inside_brackets: bool) -> None:
 
 
 def normalize_string_quotes(leaf: Leaf) -> None:
 
 
 def normalize_string_quotes(leaf: Leaf) -> None:

+    """Prefer double quotes but only if it doesn't cause more escaping.
+
+    Adds or removes backslashes as appropriate. Doesn't parse and fix
+    strings nested in f-strings (yet).
+
+    Note: Mutates its argument.
+    """

     value = leaf.value.lstrip("furbFURB")
     if value[:3] == '"""':
         return
     value = leaf.value.lstrip("furbFURB")
     if value[:3] == '"""':
         return


@@ -1862,6 +1986,7 @@ def gen_python_files_in_dir(path: Path) -> Iterator[Path]:
 class Report:
     """Provides a reformatting counter. Can be rendered with `str(report)`."""
     check: bool = False
 class Report:
     """Provides a reformatting counter. Can be rendered with `str(report)`."""
     check: bool = False

+    quiet: bool = False

     change_count: int = 0
     same_count: int = 0
     failure_count: int = 0
     change_count: int = 0
     same_count: int = 0
     failure_count: int = 0


@@ -1870,10 +1995,12 @@ class Report:
         """Increment the counter for successful reformatting. Write out a message."""
         if changed:
             reformatted = "would reformat" if self.check else "reformatted"
         """Increment the counter for successful reformatting. Write out a message."""
         if changed:
             reformatted = "would reformat" if self.check else "reformatted"

-            out(f"{reformatted} {src}")
+            if not self.quiet:
+                out(f"{reformatted} {src}")

             self.change_count += 1
         else:
             self.change_count += 1
         else:

-            out(f"{src} already well formatted, good job.", bold=False)
+            if not self.quiet:
+                out(f"{src} already well formatted, good job.", bold=False)

             self.same_count += 1
 
     def failed(self, src: Path, message: str) -> None:
             self.same_count += 1
 
     def failed(self, src: Path, message: str) -> None:


@@ -2018,7 +2145,8 @@ def dump_to_file(*output: str) -> str:
     ) as f:
         for lines in output:
             f.write(lines)
     ) as f:
         for lines in output:
             f.write(lines)

-            f.write("\n")
+            if lines and lines[-1] != "\n":
+                f.write("\n")

     return f.name
 
 
     return f.name