done

lib/python3.11/site-packages/babel/units.py

@@ -0,0 +1,340 @@
+from __future__ import annotations
+
+import decimal
+from typing import Literal
+
+from babel.core import Locale
+from babel.numbers import LC_NUMERIC, format_decimal
+
+
+class UnknownUnitError(ValueError):
+    def __init__(self, unit: str, locale: Locale) -> None:
+        ValueError.__init__(self, f"{unit} is not a known unit in {locale}")
+
+
+def get_unit_name(
+    measurement_unit: str,
+    length: Literal['short', 'long', 'narrow'] = 'long',
+    locale: Locale | str | None = None,
+) -> str | None:
+    """
+    Get the display name for a measurement unit in the given locale.
+
+    >>> get_unit_name("radian", locale="en")
+    'radians'
+
+    Unknown units will raise exceptions:
+
+    >>> get_unit_name("battery", locale="fi")
+    Traceback (most recent call last):
+        ...
+    UnknownUnitError: battery/long is not a known unit/length in fi
+
+    :param measurement_unit: the code of a measurement unit.
+                             Known units can be found in the CLDR Unit Validity XML file:
+                             https://unicode.org/repos/cldr/tags/latest/common/validity/unit.xml
+
+    :param length: "short", "long" or "narrow"
+    :param locale: the `Locale` object or locale identifier. Defaults to the system numeric locale.
+    :return: The unit display name, or None.
+    """
+    locale = Locale.parse(locale or LC_NUMERIC)
+    unit = _find_unit_pattern(measurement_unit, locale=locale)
+    if not unit:
+        raise UnknownUnitError(unit=measurement_unit, locale=locale)
+    return locale.unit_display_names.get(unit, {}).get(length)
+
+
+def _find_unit_pattern(unit_id: str, locale: Locale | str | None = None) -> str | None:
+    """
+    Expand a unit into a qualified form.
+
+    Known units can be found in the CLDR Unit Validity XML file:
+    https://unicode.org/repos/cldr/tags/latest/common/validity/unit.xml
+
+    >>> _find_unit_pattern("radian", locale="en")
+    'angle-radian'
+
+    Unknown values will return None.
+
+    >>> _find_unit_pattern("horse", locale="en")
+
+    :param unit_id: the code of a measurement unit.
+    :return: A key to the `unit_patterns` mapping, or None.
+    """
+    locale = Locale.parse(locale or LC_NUMERIC)
+    unit_patterns: dict[str, str] = locale._data["unit_patterns"]
+    if unit_id in unit_patterns:
+        return unit_id
+    for unit_pattern in sorted(unit_patterns, key=len):
+        if unit_pattern.endswith(unit_id):
+            return unit_pattern
+    return None
+
+
+def format_unit(
+    value: str | float | decimal.Decimal,
+    measurement_unit: str,
+    length: Literal['short', 'long', 'narrow'] = 'long',
+    format: str | None = None,
+    locale: Locale | str | None = None,
+    *,
+    numbering_system: Literal["default"] | str = "latn",
+) -> str:
+    """Format a value of a given unit.
+
+    Values are formatted according to the locale's usual pluralization rules
+    and number formats.
+
+    >>> format_unit(12, 'length-meter', locale='ro_RO')
+    u'12 metri'
+    >>> format_unit(15.5, 'length-mile', locale='fi_FI')
+    u'15,5 mailia'
+    >>> format_unit(1200, 'pressure-millimeter-ofhg', locale='nb')
+    u'1\\xa0200 millimeter kvikks\\xf8lv'
+    >>> format_unit(270, 'ton', locale='en')
+    u'270 tons'
+    >>> format_unit(1234.5, 'kilogram', locale='ar_EG', numbering_system='default')
+    u'1٬234٫5 كيلوغرام'
+
+    Number formats may be overridden with the ``format`` parameter.
+
+    >>> import decimal
+    >>> format_unit(decimal.Decimal("-42.774"), 'temperature-celsius', 'short', format='#.0', locale='fr')
+    u'-42,8\\u202f\\xb0C'
+
+    The locale's usual pluralization rules are respected.
+
+    >>> format_unit(1, 'length-meter', locale='ro_RO')
+    u'1 metru'
+    >>> format_unit(0, 'length-mile', locale='cy')
+    u'0 mi'
+    >>> format_unit(1, 'length-mile', locale='cy')
+    u'1 filltir'
+    >>> format_unit(3, 'length-mile', locale='cy')
+    u'3 milltir'
+
+    >>> format_unit(15, 'length-horse', locale='fi')
+    Traceback (most recent call last):
+        ...
+    UnknownUnitError: length-horse is not a known unit in fi
+
+    .. versionadded:: 2.2.0
+
+    :param value: the value to format. If this is a string, no number formatting will be attempted.
+    :param measurement_unit: the code of a measurement unit.
+                             Known units can be found in the CLDR Unit Validity XML file:
+                             https://unicode.org/repos/cldr/tags/latest/common/validity/unit.xml
+    :param length: "short", "long" or "narrow"
+    :param format: An optional format, as accepted by `format_decimal`.
+    :param locale: the `Locale` object or locale identifier. Defaults to the system numeric locale.
+    :param numbering_system: The numbering system used for formatting number symbols. Defaults to "latn".
+                             The special value "default" will use the default numbering system of the locale.
+    :raise `UnsupportedNumberingSystemError`: If the numbering system is not supported by the locale.
+    """
+    locale = Locale.parse(locale or LC_NUMERIC)
+
+    q_unit = _find_unit_pattern(measurement_unit, locale=locale)
+    if not q_unit:
+        raise UnknownUnitError(unit=measurement_unit, locale=locale)
+    unit_patterns = locale._data["unit_patterns"][q_unit].get(length, {})
+
+    if isinstance(value, str):  # Assume the value is a preformatted singular.
+        formatted_value = value
+        plural_form = "one"
+    else:
+        formatted_value = format_decimal(value, format, locale, numbering_system=numbering_system)
+        plural_form = locale.plural_form(value)
+
+    if plural_form in unit_patterns:
+        return unit_patterns[plural_form].format(formatted_value)
+
+    # Fall back to a somewhat bad representation.
+    # nb: This is marked as no-cover, as the current CLDR seemingly has no way for this to happen.
+    fallback_name = get_unit_name(measurement_unit, length=length, locale=locale)  # pragma: no cover
+    return f"{formatted_value} {fallback_name or measurement_unit}"  # pragma: no cover
+
+
+def _find_compound_unit(
+    numerator_unit: str,
+    denominator_unit: str,
+    locale: Locale | str | None = None,
+) -> str | None:
+    """
+    Find a predefined compound unit pattern.
+
+    Used internally by format_compound_unit.
+
+    >>> _find_compound_unit("kilometer", "hour", locale="en")
+    'speed-kilometer-per-hour'
+
+    >>> _find_compound_unit("mile", "gallon", locale="en")
+    'consumption-mile-per-gallon'
+
+    If no predefined compound pattern can be found, `None` is returned.
+
+    >>> _find_compound_unit("gallon", "mile", locale="en")
+
+    >>> _find_compound_unit("horse", "purple", locale="en")
+
+    :param numerator_unit: The numerator unit's identifier
+    :param denominator_unit: The denominator unit's identifier
+    :param locale: the `Locale` object or locale identifier. Defaults to the system numeric locale.
+    :return: A key to the `unit_patterns` mapping, or None.
+    :rtype: str|None
+    """
+    locale = Locale.parse(locale or LC_NUMERIC)
+
+    # Qualify the numerator and denominator units.  This will turn possibly partial
+    # units like "kilometer" or "hour" into actual units like "length-kilometer" and
+    # "duration-hour".
+
+    resolved_numerator_unit = _find_unit_pattern(numerator_unit, locale=locale)
+    resolved_denominator_unit = _find_unit_pattern(denominator_unit, locale=locale)
+
+    # If either was not found, we can't possibly build a suitable compound unit either.
+    if not (resolved_numerator_unit and resolved_denominator_unit):
+        return None
+
+    # Since compound units are named "speed-kilometer-per-hour", we'll have to slice off
+    # the quantities (i.e. "length", "duration") from both qualified units.
+
+    bare_numerator_unit = resolved_numerator_unit.split("-", 1)[-1]
+    bare_denominator_unit = resolved_denominator_unit.split("-", 1)[-1]
+
+    # Now we can try and rebuild a compound unit specifier, then qualify it:
+
+    return _find_unit_pattern(f"{bare_numerator_unit}-per-{bare_denominator_unit}", locale=locale)
+
+
+def format_compound_unit(
+    numerator_value: str | float | decimal.Decimal,
+    numerator_unit: str | None = None,
+    denominator_value: str | float | decimal.Decimal = 1,
+    denominator_unit: str | None = None,
+    length: Literal["short", "long", "narrow"] = "long",
+    format: str | None = None,
+    locale: Locale | str | None = None,
+    *,
+    numbering_system: Literal["default"] | str = "latn",
+) -> str | None:
+    """
+    Format a compound number value, i.e. "kilometers per hour" or similar.
+
+    Both unit specifiers are optional to allow for formatting of arbitrary values still according
+    to the locale's general "per" formatting specifier.
+
+    >>> format_compound_unit(7, denominator_value=11, length="short", locale="pt")
+    '7/11'
+
+    >>> format_compound_unit(150, "kilometer", denominator_unit="hour", locale="sv")
+    '150 kilometer per timme'
+
+    >>> format_compound_unit(150, "kilowatt", denominator_unit="year", locale="fi")
+    '150 kilowattia / vuosi'
+
+    >>> format_compound_unit(32.5, "ton", 15, denominator_unit="hour", locale="en")
+    '32.5 tons per 15 hours'
+
+    >>> format_compound_unit(1234.5, "ton", 15, denominator_unit="hour", locale="ar_EG", numbering_system="arab")
+    '1٬234٫5 طن لكل 15 ساعة'
+
+    >>> format_compound_unit(160, denominator_unit="square-meter", locale="fr")
+    '160 par m\\xe8tre carr\\xe9'
+
+    >>> format_compound_unit(4, "meter", "ratakisko", length="short", locale="fi")
+    '4 m/ratakisko'
+
+    >>> format_compound_unit(35, "minute", denominator_unit="nautical-mile", locale="sv")
+    '35 minuter per nautisk mil'
+
+    >>> from babel.numbers import format_currency
+    >>> format_compound_unit(format_currency(35, "JPY", locale="de"), denominator_unit="liter", locale="de")
+    '35\\xa0\\xa5 pro Liter'
+
+    See https://www.unicode.org/reports/tr35/tr35-general.html#perUnitPatterns
+
+    :param numerator_value: The numerator value. This may be a string,
+                            in which case it is considered preformatted and the unit is ignored.
+    :param numerator_unit: The numerator unit. See `format_unit`.
+    :param denominator_value: The denominator value. This may be a string,
+                              in which case it is considered preformatted and the unit is ignored.
+    :param denominator_unit: The denominator unit. See `format_unit`.
+    :param length: The formatting length. "short", "long" or "narrow"
+    :param format: An optional format, as accepted by `format_decimal`.
+    :param locale: the `Locale` object or locale identifier. Defaults to the system numeric locale.
+    :param numbering_system: The numbering system used for formatting number symbols. Defaults to "latn".
+                             The special value "default" will use the default numbering system of the locale.
+    :return: A formatted compound value.
+    :raise `UnsupportedNumberingSystemError`: If the numbering system is not supported by the locale.
+    """
+    locale = Locale.parse(locale or LC_NUMERIC)
+
+    # Look for a specific compound unit first...
+
+    if numerator_unit and denominator_unit and denominator_value == 1:
+        compound_unit = _find_compound_unit(numerator_unit, denominator_unit, locale=locale)
+        if compound_unit:
+            return format_unit(
+                numerator_value,
+                compound_unit,
+                length=length,
+                format=format,
+                locale=locale,
+                numbering_system=numbering_system,
+            )
+
+    # ... failing that, construct one "by hand".
+
+    if isinstance(numerator_value, str):  # Numerator is preformatted
+        formatted_numerator = numerator_value
+    elif numerator_unit:  # Numerator has unit
+        formatted_numerator = format_unit(
+            numerator_value,
+            numerator_unit,
+            length=length,
+            format=format,
+            locale=locale,
+            numbering_system=numbering_system,
+        )
+    else:  # Unitless numerator
+        formatted_numerator = format_decimal(
+            numerator_value,
+            format=format,
+            locale=locale,
+            numbering_system=numbering_system,
+        )
+
+    if isinstance(denominator_value, str):  # Denominator is preformatted
+        formatted_denominator = denominator_value
+    elif denominator_unit:  # Denominator has unit
+        if denominator_value == 1:  # support perUnitPatterns when the denominator is 1
+            denominator_unit = _find_unit_pattern(denominator_unit, locale=locale)
+            per_pattern = locale._data["unit_patterns"].get(denominator_unit, {}).get(length, {}).get("per")
+            if per_pattern:
+                return per_pattern.format(formatted_numerator)
+            # See TR-35's per-unit pattern algorithm, point 3.2.
+            # For denominator 1, we replace the value to be formatted with the empty string;
+            # this will make `format_unit` return " second" instead of "1 second".
+            denominator_value = ""
+
+        formatted_denominator = format_unit(
+            denominator_value,
+            measurement_unit=(denominator_unit or ""),
+            length=length,
+            format=format,
+            locale=locale,
+            numbering_system=numbering_system,
+        ).strip()
+    else:  # Bare denominator
+        formatted_denominator = format_decimal(
+            denominator_value,
+            format=format,
+            locale=locale,
+            numbering_system=numbering_system,
+        )
+
+    # TODO: this doesn't support "compound_variations" (or "prefix"), and will fall back to the "x/y" representation
+    per_pattern = locale._data["compound_unit_patterns"].get("per", {}).get(length, {}).get("compound", "{0}/{1}")
+
+    return per_pattern.format(formatted_numerator, formatted_denominator)