remove unreachable code (#3328)

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

diff --git a/src/black/__init__.py b/src/black/__init__.py
index afc76e1fa0cb5e7dda1a51544718ef778e846344..5293796aea1cecac7dc83f994ed4a1ecfa3b47bb 100644 (file)
--- a/src/black/__init__.py
+++ b/src/black/__init__.py
@@ -1,6 +1,5 @@
 import io
 import json
-import os
 import platform
 import re
 import sys
@@ -28,11 +27,6 @@ from typing import (
     Union,
 )
 
-if sys.version_info >= (3, 8):
-    from typing import Final
-else:
-    from typing_extensions import Final
-
 import click
 from click.core import ParameterSource
 from mypy_extensions import mypyc_attr
@@ -92,7 +86,6 @@ from blib2to3.pgen2 import token
 from blib2to3.pytree import Leaf, Node
 
 COMPILED = Path(__file__).suffix in (".pyd", ".so")
-DEFAULT_WORKERS: Final = os.cpu_count()
 
 # types
 FileContent = str
@@ -255,6 +248,12 @@ def validate_regex(
     ),
     default=[],
 )
+@click.option(
+    "-x",
+    "--skip-source-first-line",
+    is_flag=True,
+    help="Skip the first line of the source code.",
+)
 @click.option(
     "-S",
     "--skip-string-normalization",
@@ -371,9 +370,8 @@ def validate_regex(
     "-W",
     "--workers",
     type=click.IntRange(min=1),
-    default=DEFAULT_WORKERS,
-    show_default=True,
-    help="Number of parallel workers",
+    default=None,
+    help="Number of parallel workers [default: number of CPUs in the system]",
 )
 @click.option(
     "-q",
@@ -436,6 +434,7 @@ def main(  # noqa: C901
     pyi: bool,
     ipynb: bool,
     python_cell_magics: Sequence[str],
+    skip_source_first_line: bool,
     skip_string_normalization: bool,
     skip_magic_trailing_comma: bool,
     experimental_string_processing: bool,
@@ -448,7 +447,7 @@ def main(  # noqa: C901
     extend_exclude: Optional[Pattern[str]],
     force_exclude: Optional[Pattern[str]],
     stdin_filename: Optional[str],
-    workers: int,
+    workers: Optional[int],
     src: Tuple[str, ...],
     config: Optional[str],
 ) -> None:
@@ -536,6 +535,7 @@ def main(  # noqa: C901
         line_length=line_length,
         is_pyi=pyi,
         is_ipynb=ipynb,
+        skip_source_first_line=skip_source_first_line,
         string_normalization=not skip_string_normalization,
         magic_trailing_comma=not skip_magic_trailing_comma,
         experimental_string_processing=experimental_string_processing,
@@ -623,12 +623,7 @@ def get_sources(
 ) -> Set[Path]:
     """Compute the set of files to be formatted."""
     sources: Set[Path] = set()
-
-    if exclude is None:
-        exclude = re_compile_maybe_verbose(DEFAULT_EXCLUDES)
-        gitignore = get_gitignore(ctx.obj["root"])
-    else:
-        gitignore = None
+    root = ctx.obj["root"]
 
     for s in src:
         if s == "-" and stdin_filename:
@@ -663,6 +658,16 @@ def get_sources(
 
             sources.add(p)
         elif p.is_dir():
+            if exclude is None:
+                exclude = re_compile_maybe_verbose(DEFAULT_EXCLUDES)
+                gitignore = get_gitignore(root)
+                p_gitignore = get_gitignore(p)
+                # No need to use p's gitignore if it is identical to root's gitignore
+                # (i.e. root and p point to the same directory).
+                if gitignore != p_gitignore:
+                    gitignore += p_gitignore
+            else:
+                gitignore = None
             sources.update(
                 gen_python_files(
                     p.iterdir(),
@@ -793,7 +798,10 @@ def format_file_in_place(
         mode = replace(mode, is_ipynb=True)
 
     then = datetime.utcfromtimestamp(src.stat().st_mtime)
+    header = b""
     with open(src, "rb") as buf:
+        if mode.skip_source_first_line:
+            header = buf.readline()
         src_contents, encoding, newline = decode_bytes(buf.read())
     try:
         dst_contents = format_file_contents(src_contents, fast=fast, mode=mode)
@@ -803,6 +811,8 @@ def format_file_in_place(
         raise ValueError(
             f"File '{src}' cannot be parsed as valid Jupyter notebook."
         ) from None
+    src_contents = header.decode(encoding) + src_contents
+    dst_contents = header.decode(encoding) + dst_contents
 
     if write_back == WriteBack.YES:
         with open(src, "w", encoding=encoding, newline=newline) as f:
@@ -1372,13 +1382,15 @@ def patch_click() -> None:
 
     for module in modules:
         if hasattr(module, "_verify_python3_env"):
-            module._verify_python3_env = lambda: None  # type: ignore
+            module._verify_python3_env = lambda: None
         if hasattr(module, "_verify_python_env"):
-            module._verify_python_env = lambda: None  # type: ignore
+            module._verify_python_env = lambda: None
 
 
 def patched_main() -> None:
-    if sys.platform == "win32" and getattr(sys, "frozen", False):
+    # PyInstaller patches multiprocessing to need freeze_support() even in non-Windows
+    # environments so just assume we always need to call it if frozen.
+    if getattr(sys, "frozen", False):
         from multiprocessing import freeze_support
 
         freeze_support()