python_format.py

#!/usr/bin/env python3

# This source file is part of the Swift.org open source project
#
# Copyright (c) 2014 - 2020 Apple Inc. and the Swift project authors
# Licensed under Apache License v2.0 with Runtime Library Exception
#
# See https://swift.org/LICENSE.txt for license information
# See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors


"""
Utility script used to run the black code formatter over all the Python scripts in the
project sources.
"""


importargparse
importos
importsubprocess
importsys
frompathlibimportPath


_SWIFT_PATH=Path(__file__).resolve().parents[1]

_KNOWN_SCRIPT_PATHS= [
_SWIFT_PATH/"benchmark/scripts/Benchmark_Driver",
_SWIFT_PATH/"benchmark/scripts/Benchmark_DTrace.in",
_SWIFT_PATH/"benchmark/scripts/Benchmark_GuardMalloc.in",
_SWIFT_PATH/"benchmark/scripts/Benchmark_QuickCheck.in",
_SWIFT_PATH/"benchmark/scripts/Benchmark_RuntimeLeaksRunner.in",
_SWIFT_PATH/"benchmark/scripts/run_smoke_bench",
_SWIFT_PATH/"docs/scripts/ns-html2rst",
_SWIFT_PATH/"test/Driver/Inputs/fake-toolchain/ld",
_SWIFT_PATH/"utils/80+-check",
_SWIFT_PATH/"utils/backtrace-check",
_SWIFT_PATH/"utils/build-script",
_SWIFT_PATH/"utils/check-incremental",
_SWIFT_PATH/"utils/coverage/coverage-build-db",
_SWIFT_PATH/"utils/coverage/coverage-generate-data",
_SWIFT_PATH/"utils/coverage/coverage-query-db",
_SWIFT_PATH/"utils/coverage/coverage-touch-tests",
_SWIFT_PATH/"utils/dev-scripts/blockifyasm",
_SWIFT_PATH/"utils/dev-scripts/split-cmdline",
_SWIFT_PATH/"utils/gyb",
_SWIFT_PATH/"utils/line-directive",
_SWIFT_PATH/"utils/PathSanitizingFileCheck",
_SWIFT_PATH/"utils/recursive-lipo",
_SWIFT_PATH/"utils/round-trip-syntax-test",
_SWIFT_PATH/"utils/rth",
_SWIFT_PATH/"utils/run-test",
_SWIFT_PATH/"utils/scale-test",
_SWIFT_PATH/"utils/submit-benchmark-results",
_SWIFT_PATH/"utils/swift_build_support/tests/mock-distcc",
_SWIFT_PATH/"utils/symbolicate-linux-fatal",
_SWIFT_PATH/"utils/update-checkout",
_SWIFT_PATH/"utils/viewcfg",
]


_INSTALL_BLACK_MESSAGE="""\
The black Python package is required for formatting, but it was not found on
your system.

You can install it using:

 python3 -m pip install black

For more help, see https://black.readthedocs.io.
"""


def_get_python_sources():
"""Returns a list of path objects for all known Python sources in the Swift
 project.
 """

returnlist(_SWIFT_PATH.rglob("*.py")) +_KNOWN_SCRIPT_PATHS


def_is_package_installed(name):
"""Runs the pip command to check if a package is installed.
 """

command= [
sys.executable,
"-m",
"pip",
"show",
"--quiet",
name,
 ]

withopen(os.devnull, "w") asdevnull:
status=subprocess.call(command, stderr=devnull)

returnnotstatus


defparse_args():
parser=argparse.ArgumentParser()

parser.add_argument(
"paths",
type=Path,
metavar="PATH",
nargs="*",
help="Source path to format.",
 )

parser.add_argument(
"--check",
action="store_true",
help="Don't write the files back, just return the status.",
 )

parser.add_argument(
"-v",
"--verbose",
action="store_true",
help="Emit messages to stderr about files that were not changed.",
 )

parser.add_argument(
"--diff",
action="store_true",
help="Don't write the files back, just output a diff for each file on stdout.",
 )

parser.add_argument(
"-S",
"--skip-string-normalization",
action="store_true",
help="Don't normalize string quotes or prefixes.",
 )

returnparser.parse_args()


defmain():
args=parse_args()

ifnot_is_package_installed("black"):
print(_INSTALL_BLACK_MESSAGE)
return1

command= [
sys.executable,
"-m",
"black",
"--target-version",
"py38",
 ]

ifargs.check:
command.append("--check")
ifargs.verbose:
command.append("--verbose")
ifargs.diff:
command.append("--diff")
ifargs.skip_string_normalization:
command.append("--skip-string-normalization")

requested_paths= [path.resolve() forpathinargs.paths]

# Narrow down the set of paths to format to only those paths which are either
# included in the set of requested paths or are subpaths of the requested paths.
format_paths= {
known_path
forpathinrequested_paths
forknown_pathin_get_python_sources()
ifpath==known_pathorpathinknown_path.parents
 }

# Add requested paths that exists, but aren't included in the format set.
forpathinrequested_paths:
ifpathnotinformat_pathsandpath.exists():
format_paths.add(path)

command+=sorted([str(path) forpathinformat_paths])

returnsubprocess.call(command)


if__name__=="__main__":
sys.exit(main())