nassh/bin/filter_translations.py

#!/usr/bin/env python3
# Copyright 2017 The ChromiumOS Authors
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

"""Reformat the JSON we get from the translators.

Use pure UTF-8, pretty-print, and sort.  This should (hopefully) make diffs in
future updates smaller, and shrink the size of the file itself in the extension.
"""

import json
import re
import sys

import nassh  # pylint: disable=unused-import,wrong-import-order
import libdot


def trim_redundant_placeholders(data):
    """Remove redundant placeholders entries.

    For messages that look like:
      "command_complete": {
        "message": "The command $1 exited with status code $2.",
        "placeholders": {
          "1": {
            "content": "$1"
          },
          "2": {
            "content": "$2"
          }
        }
      },

    We can delete the placeholders entirely.
    """
    for msg in data.values():
        for key, settings in list(msg.get("placeholders", {}).items()):
            if re.match(r"^[0-9]+$", key) and re.match(
                r"^[$][0-9]+$", settings["content"]
            ):
                msg["placeholders"].pop(key)

        # Remove the placeholders setting if it's empty now.
        placeholders = msg.get("placeholders", {})
        if not placeholders:
            msg.pop("placeholders", None)


def reformat(path, output=None, inplace=False):
    """Reformat translation."""
    if isinstance(path, dict):
        data = path
    else:
        with open(path, "rb") as fp:
            try:
                data = json.loads(fp.read())
            except ValueError as e:
                print(f"ERROR: Processing {path}: {e}", file=sys.stderr)
                return False

    trim_redundant_placeholders(data)
    data.pop("migrate_to_ext", None)

    format_spaces = json.dumps(
        data, ensure_ascii=False, indent=4, sort_keys=True
    )
    format_tabs = re.sub(
        "^(    )+",
        lambda match: "\t" * (len(match.group()) // 4),
        format_spaces,
        flags=re.M,
    )
    format_tabs += "\n"

    if inplace:
        output = path
    if output:
        with open(output, "w", encoding="utf-8") as fp:
            fp.write(format_tabs)
    else:
        sys.stdout.write(format_tabs)

    return True


def get_parser():
    """Get a command line parser."""
    parser = libdot.ArgumentParser(description=__doc__)
    parser.add_argument(
        "-i",
        "--inplace",
        default=False,
        action="store_true",
        help="Modify files inline rather than writing stdout.",
    )
    parser.add_argument(
        "files", nargs="+", metavar="files", help="The translations to format."
    )
    return parser


def main(argv):
    """The main func!"""
    parser = get_parser()
    opts = parser.parse_args(argv)

    ret = 0
    for path in opts.files:
        if not reformat(path, inplace=opts.inplace):
            ret = 1
    return ret


if __name__ == "__main__":
    sys.exit(main(sys.argv[1:]))