Add option to skip the first line of source code (#3299)

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

diff --git a/src/black/__init__.py b/src/black/__init__.py
index 86a0b63744264c85dc23f8702768d333c047f221..afd71e519162eeda6643aa3ff22ca9e9b060f6af 100644 (file)
--- a/src/black/__init__.py
+++ b/src/black/__init__.py
@@ -248,6 +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",
@@ -428,6 +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,
@@ -528,6 +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,
@@ -653,6 +661,11 @@ def get_sources(
             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(
@@ -785,7 +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)
@@ -795,6 +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:
@@ -1370,7 +1388,9 @@ def patch_click() -> 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()