runtime/Lib/site-packages/charset_normalizer/legacy.py

import warnings
from typing import Dict, Optional, Union

from .api import from_bytes, from_fp, from_path, normalize
from .constant import CHARDET_CORRESPONDENCE
from .models import CharsetMatch, CharsetMatches


def detect(byte_str: bytes) -> Dict[str, Optional[Union[str, float]]]:
    """
    chardet legacy method
    Detect the encoding of the given byte string. It should be mostly backward-compatible.
    Encoding name will match Chardet own writing whenever possible. (Not on encoding name unsupported by it)
    This function is deprecated and should be used to migrate your project easily, consult the documentation for
    further information. Not planned for removal.

    :param byte_str:     The byte sequence to examine.
    """
    if not isinstance(byte_str, (bytearray, bytes)):
        raise TypeError(  # pragma: nocover
            "Expected object of type bytes or bytearray, got: "
            "{0}".format(type(byte_str))
        )

    if isinstance(byte_str, bytearray):
        byte_str = bytes(byte_str)

    r = from_bytes(byte_str).best()

    encoding = r.encoding if r is not None else None
    language = r.language if r is not None and r.language != "Unknown" else ""
    confidence = 1.0 - r.chaos if r is not None else None

    # Note: CharsetNormalizer does not return 'UTF-8-SIG' as the sig get stripped in the detection/normalization process
    # but chardet does return 'utf-8-sig' and it is a valid codec name.
    if r is not None and encoding == "utf_8" and r.bom:
        encoding += "_sig"

    return {
        "encoding": encoding
        if encoding not in CHARDET_CORRESPONDENCE
        else CHARDET_CORRESPONDENCE[encoding],
        "language": language,
        "confidence": confidence,
    }


class CharsetNormalizerMatch(CharsetMatch):
    pass


class CharsetNormalizerMatches(CharsetMatches):
    @staticmethod
    def from_fp(*args, **kwargs):  # type: ignore
        warnings.warn(  # pragma: nocover
            "staticmethod from_fp, from_bytes, from_path and normalize are deprecated "
            "and scheduled to be removed in 3.0",
            DeprecationWarning,
        )
        return from_fp(*args, **kwargs)  # pragma: nocover

    @staticmethod
    def from_bytes(*args, **kwargs):  # type: ignore
        warnings.warn(  # pragma: nocover
            "staticmethod from_fp, from_bytes, from_path and normalize are deprecated "
            "and scheduled to be removed in 3.0",
            DeprecationWarning,
        )
        return from_bytes(*args, **kwargs)  # pragma: nocover

    @staticmethod
    def from_path(*args, **kwargs):  # type: ignore
        warnings.warn(  # pragma: nocover
            "staticmethod from_fp, from_bytes, from_path and normalize are deprecated "
            "and scheduled to be removed in 3.0",
            DeprecationWarning,
        )
        return from_path(*args, **kwargs)  # pragma: nocover

    @staticmethod
    def normalize(*args, **kwargs):  # type: ignore
        warnings.warn(  # pragma: nocover
            "staticmethod from_fp, from_bytes, from_path and normalize are deprecated "
            "and scheduled to be removed in 3.0",
            DeprecationWarning,
        )
        return normalize(*args, **kwargs)  # pragma: nocover


class CharsetDetector(CharsetNormalizerMatches):
    pass


class CharsetDoctor(CharsetNormalizerMatches):
    pass