def main()

in tools/run-clang-tidy.py [0:0]

• 161 lines of code
• 24 McCabe index (conditional complexity)

def main():
    parser = argparse.ArgumentParser(
        description="Runs clang-tidy over all files "
        "in a compilation database. Requires "
        "clang-tidy and clang-apply-replacements in "
        "$PATH."
    )
    parser.add_argument(
        "-clang-tidy-binary",
        metavar="PATH",
        default="clang-tidy",
        help="path to clang-tidy binary",
    )
    parser.add_argument(
        "-clang-apply-replacements-binary",
        metavar="PATH",
        default="clang-apply-replacements",
        help="path to clang-apply-replacements binary",
    )
    parser.add_argument(
        "-checks",
        default=None,
        help="checks filter, when not specified, use clang-tidy " "default",
    )
    parser.add_argument(
        "-config",
        default=None,
        help="Specifies a configuration in YAML/JSON format: "
        "  -config=\"{Checks: '*', "
        "                       CheckOptions: [{key: x, "
        '                                       value: y}]}" '
        "When the value is empty, clang-tidy will "
        "attempt to find a file named .clang-tidy for "
        "each source file in its parent directories.",
    )
    parser.add_argument(
        "-header-filter",
        default=None,
        help="regular expression matching the names of the "
        "headers to output diagnostics from. Diagnostics from "
        "the main file of each translation unit are always "
        "displayed.",
    )
    if yaml:
        parser.add_argument(
            "-export-fixes",
            metavar="filename",
            dest="export_fixes",
            help="Create a yaml file to store suggested fixes in, "
            "which can be applied with clang-apply-replacements.",
        )
    parser.add_argument(
        "-j",
        type=int,
        default=0,
        help="number of tidy instances to be run in parallel.",
    )
    parser.add_argument(
        "files", nargs="*", default=[".*"], help="files to be processed (regex on path)"
    )
    parser.add_argument("-fix", action="store_true", help="apply fix-its")
    parser.add_argument(
        "-format", action="store_true", help="Reformat code " "after applying fixes"
    )
    parser.add_argument(
        "-style",
        default="file",
        help="The style of reformat " "code after applying fixes",
    )
    parser.add_argument(
        "-p", dest="build_path", help="Path used to read a compile command database."
    )
    parser.add_argument(
        "-extra-arg",
        dest="extra_arg",
        action="append",
        default=[],
        help="Additional argument to append to the compiler " "command line.",
    )
    parser.add_argument(
        "-extra-arg-before",
        dest="extra_arg_before",
        action="append",
        default=[],
        help="Additional argument to prepend to the compiler " "command line.",
    )
    parser.add_argument(
        "-quiet", action="store_true", help="Run clang-tidy in quiet mode"
    )
    args = parser.parse_args()

    db_path = "compile_commands.json"

    if args.build_path is not None:
        build_path = args.build_path
    else:
        # Find our database
        build_path = find_compilation_database(db_path)

    try:
        invocation = [args.clang_tidy_binary, "-list-checks"]
        invocation.append("-p=" + build_path)
        if args.checks:
            invocation.append("-checks=" + args.checks)
        invocation.append("-")
        if args.quiet:
            # Even with -quiet we still want to check if we can call clang-tidy.
            with open(os.devnull, "w") as dev_null:
                subprocess.check_call(invocation, stdout=dev_null)
        else:
            subprocess.check_call(invocation)
    except:
        print("Unable to run clang-tidy.", file=sys.stderr)
        sys.exit(1)

    # Load the database and extract all files.
    database = json.load(open(os.path.join(build_path, db_path)))
    files = [make_absolute(entry["file"], entry["directory"]) for entry in database]

    max_task = args.j
    if max_task == 0:
        max_task = multiprocessing.cpu_count()

    tmpdir = None
    if args.fix or (yaml and args.export_fixes):
        check_clang_apply_replacements_binary(args)
        tmpdir = tempfile.mkdtemp()

    # Build up a big regexy filter from all command line arguments.
    file_name_re = re.compile("|".join(args.files))

    return_code = 0
    try:
        # Spin up a bunch of tidy-launching threads.
        task_queue = queue.Queue(max_task)
        # List of files with a non-zero return code.
        failed_files = []
        lock = threading.Lock()
        for _ in range(max_task):
            t = threading.Thread(
                target=run_tidy,
                args=(args, tmpdir, build_path, task_queue, lock, failed_files),
            )
            t.daemon = True
            t.start()

        # Fill the queue with files.
        for name in files:
            if file_name_re.search(name):
                task_queue.put(name)

        # Wait for all threads to be done.
        task_queue.join()
        if len(failed_files):
            return_code = 1

    except KeyboardInterrupt:
        # This is a sad hack. Unfortunately subprocess goes
        # bonkers with ctrl-c and we start forking merrily.
        print("\nCtrl-C detected, goodbye.")
        if tmpdir:
            shutil.rmtree(tmpdir)
        os.kill(0, 9)

    if yaml and args.export_fixes:
        print("Writing fixes to " + args.export_fixes + " ...")
        try:
            merge_replacement_files(tmpdir, args.export_fixes)
        except:
            print("Error exporting fixes.\n", file=sys.stderr)
            traceback.print_exc()
            return_code = 1

    if args.fix:
        print("Applying fixes ...")
        try:
            apply_fixes(args, tmpdir)
        except:
            print("Error applying fixes.\n", file=sys.stderr)
            traceback.print_exc()
            return_code = 1

    if tmpdir:
        shutil.rmtree(tmpdir)
    sys.exit(return_code)