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// This file is part of ICU4X. For terms of use, please see the file
// called LICENSE at the top level of the ICU4X source tree
// (online at: https://github.com/unicode-org/icu4x/blob/main/LICENSE ).
use crate::compactdecimal::{
format::FormattedCompactDecimal,
options::CompactDecimalFormatterOptions,
provider::{
CompactDecimalPatternDataV1, Count, LongCompactDecimalFormatDataV1Marker, PatternULE,
ShortCompactDecimalFormatDataV1Marker,
},
ExponentError,
};
use alloc::borrow::Cow;
use core::convert::TryFrom;
use fixed_decimal::{CompactDecimal, FixedDecimal};
use icu_decimal::{FixedDecimalFormatter, FixedDecimalFormatterPreferences};
use icu_locale_core::preferences::{
define_preferences, extensions::unicode::keywords::NumberingSystem, prefs_convert,
};
use icu_plurals::{PluralRules, PluralRulesPreferences};
use icu_provider::DataError;
use icu_provider::{marker::ErasedMarker, prelude::*};
use zerovec::maps::ZeroMap2dCursor;
define_preferences!(
/// The preferences for compact decimal formatting.
[Copy]
CompactDecimalFormatterPreferences,
{
numbering_system: NumberingSystem
}
);
prefs_convert!(
CompactDecimalFormatterPreferences,
FixedDecimalFormatterPreferences,
{ numbering_system }
);
prefs_convert!(CompactDecimalFormatterPreferences, PluralRulesPreferences);
/// A formatter that renders locale-sensitive compact numbers.
///
/// # Examples
///
/// ```
/// use icu::experimental::compactdecimal::CompactDecimalFormatter;
/// use icu::locale::locale;
/// use writeable::assert_writeable_eq;
///
/// let short_french = CompactDecimalFormatter::try_new_short(
/// locale!("fr").into(),
/// Default::default(),
/// ).unwrap();
///
/// let [long_french, long_japanese, long_bangla] = [locale!("fr"), locale!("ja"), locale!("bn")]
/// .map(|locale| {
/// CompactDecimalFormatter::try_new_long(
/// locale.into(),
/// Default::default(),
/// )
/// .unwrap()
/// });
///
/// /// Supports short and long notations:
/// # // The following line contains U+00A0 NO-BREAK SPACE.
/// assert_writeable_eq!(short_french.format_i64(35_357_670), "35 M");
/// assert_writeable_eq!(long_french.format_i64(35_357_670), "35 millions");
/// /// The powers of ten used are locale-dependent:
/// assert_writeable_eq!(long_japanese.format_i64(3535_7670), "3536万");
/// /// So are the digits:
/// assert_writeable_eq!(long_bangla.format_i64(3_53_57_670), "৩.৫ কোটি");
///
/// /// The output does not always contain digits:
/// assert_writeable_eq!(long_french.format_i64(1000), "mille");
/// ```
#[derive(Debug)]
pub struct CompactDecimalFormatter {
pub(crate) plural_rules: PluralRules,
pub(crate) fixed_decimal_formatter: FixedDecimalFormatter,
pub(crate) compact_data: DataPayload<ErasedMarker<CompactDecimalPatternDataV1<'static>>>,
}
impl CompactDecimalFormatter {
/// Constructor that takes a selected locale and a list of preferences,
/// then collects all compiled data necessary to format numbers in short compact
/// decimal notation for the given locale.
///
/// ✨ *Enabled with the `compiled_data` Cargo feature.*
///
/// [📚 Help choosing a constructor](icu_provider::constructors)
///
/// # Examples
///
/// ```
/// use icu::experimental::compactdecimal::CompactDecimalFormatter;
/// use icu::locale::locale;
///
/// CompactDecimalFormatter::try_new_short(
/// locale!("sv").into(),
/// Default::default(),
/// );
/// ```
#[cfg(feature = "compiled_data")]
pub fn try_new_short(
prefs: CompactDecimalFormatterPreferences,
options: CompactDecimalFormatterOptions,
) -> Result<Self, DataError> {
let locale = DataLocale::from_preferences_locale::<ShortCompactDecimalFormatDataV1Marker>(
prefs.locale_prefs,
);
Ok(Self {
fixed_decimal_formatter: FixedDecimalFormatter::try_new(
(&prefs).into(),
options.fixed_decimal_formatter_options,
)?,
plural_rules: PluralRules::try_new_cardinal((&prefs).into())?,
compact_data: DataProvider::<ShortCompactDecimalFormatDataV1Marker>::load(
&crate::provider::Baked,
DataRequest {
id: DataIdentifierBorrowed::for_locale(&locale),
..Default::default()
},
)?
.payload
.cast(),
})
}
icu_provider::gen_any_buffer_data_constructors!(
(prefs: CompactDecimalFormatterPreferences, options: CompactDecimalFormatterOptions) -> error: DataError,
functions: [
try_new_short: skip,
try_new_short_with_any_provider,
try_new_short_with_buffer_provider,
try_new_short_unstable,
Self,
]
);
#[doc = icu_provider::gen_any_buffer_unstable_docs!(UNSTABLE, Self::try_new_short)]
pub fn try_new_short_unstable<D>(
provider: &D,
prefs: CompactDecimalFormatterPreferences,
options: CompactDecimalFormatterOptions,
) -> Result<Self, DataError>
where
D: DataProvider<ShortCompactDecimalFormatDataV1Marker>
+ DataProvider<icu_decimal::provider::DecimalSymbolsV2Marker>
+ DataProvider<icu_decimal::provider::DecimalDigitsV1Marker>
+ DataProvider<icu_plurals::provider::CardinalV1Marker>
+ ?Sized,
{
let locale = DataLocale::from_preferences_locale::<ShortCompactDecimalFormatDataV1Marker>(
prefs.locale_prefs,
);
Ok(Self {
fixed_decimal_formatter: FixedDecimalFormatter::try_new_unstable(
provider,
(&prefs).into(),
options.fixed_decimal_formatter_options,
)?,
plural_rules: PluralRules::try_new_cardinal_unstable(provider, (&prefs).into())?,
compact_data: DataProvider::<ShortCompactDecimalFormatDataV1Marker>::load(
provider,
DataRequest {
id: DataIdentifierBorrowed::for_locale(&locale),
..Default::default()
},
)?
.payload
.cast(),
})
}
/// Constructor that takes a selected locale and a list of preferences,
/// then collects all compiled data necessary to format numbers in short compact
/// decimal notation for the given locale.
///
/// ✨ *Enabled with the `compiled_data` Cargo feature.*
///
/// [📚 Help choosing a constructor](icu_provider::constructors)
///
/// # Examples
///
/// ```
/// use icu::experimental::compactdecimal::CompactDecimalFormatter;
/// use icu::locale::locale;
///
/// CompactDecimalFormatter::try_new_long(
/// locale!("sv").into(),
/// Default::default(),
/// );
/// ```
#[cfg(feature = "compiled_data")]
pub fn try_new_long(
prefs: CompactDecimalFormatterPreferences,
options: CompactDecimalFormatterOptions,
) -> Result<Self, DataError> {
let locale = DataLocale::from_preferences_locale::<LongCompactDecimalFormatDataV1Marker>(
prefs.locale_prefs,
);
Ok(Self {
fixed_decimal_formatter: FixedDecimalFormatter::try_new(
(&prefs).into(),
options.fixed_decimal_formatter_options,
)?,
plural_rules: PluralRules::try_new_cardinal((&prefs).into())?,
compact_data: DataProvider::<LongCompactDecimalFormatDataV1Marker>::load(
&crate::provider::Baked,
DataRequest {
id: DataIdentifierBorrowed::for_locale(&locale),
..Default::default()
},
)?
.payload
.cast(),
})
}
icu_provider::gen_any_buffer_data_constructors!(
(prefs: CompactDecimalFormatterPreferences, options: CompactDecimalFormatterOptions) -> error: DataError,
functions: [
try_new_long: skip,
try_new_long_with_any_provider,
try_new_long_with_buffer_provider,
try_new_long_unstable,
Self,
]
);
#[doc = icu_provider::gen_any_buffer_unstable_docs!(UNSTABLE, Self::try_new_long)]
pub fn try_new_long_unstable<D>(
provider: &D,
prefs: CompactDecimalFormatterPreferences,
options: CompactDecimalFormatterOptions,
) -> Result<Self, DataError>
where
D: DataProvider<LongCompactDecimalFormatDataV1Marker>
+ DataProvider<icu_decimal::provider::DecimalSymbolsV2Marker>
+ DataProvider<icu_decimal::provider::DecimalDigitsV1Marker>
+ DataProvider<icu_plurals::provider::CardinalV1Marker>
+ ?Sized,
{
let locale = DataLocale::from_preferences_locale::<LongCompactDecimalFormatDataV1Marker>(
prefs.locale_prefs,
);
Ok(Self {
fixed_decimal_formatter: FixedDecimalFormatter::try_new_unstable(
provider,
(&prefs).into(),
options.fixed_decimal_formatter_options,
)?,
plural_rules: PluralRules::try_new_cardinal_unstable(provider, (&prefs).into())?,
compact_data: DataProvider::<LongCompactDecimalFormatDataV1Marker>::load(
provider,
DataRequest {
id: DataIdentifierBorrowed::for_locale(&locale),
..Default::default()
},
)?
.payload
.cast(),
})
}
/// Formats an integer in compact decimal notation using the default
/// precision settings.
///
/// The result may have a fractional digit only if it is compact and its
/// significand is less than 10. Trailing fractional 0s are omitted, and
/// a sign is shown only for negative values.
///
/// # Examples
///
/// ```
/// use icu::experimental::compactdecimal::CompactDecimalFormatter;
/// use icu::locale::locale;
/// use writeable::assert_writeable_eq;
///
/// let short_english = CompactDecimalFormatter::try_new_short(
/// locale!("en").into(),
/// Default::default(),
/// )
/// .unwrap();
///
/// assert_writeable_eq!(short_english.format_i64(0), "0");
/// assert_writeable_eq!(short_english.format_i64(2), "2");
/// assert_writeable_eq!(short_english.format_i64(843), "843");
/// assert_writeable_eq!(short_english.format_i64(2207), "2.2K");
/// assert_writeable_eq!(short_english.format_i64(15_127), "15K");
/// assert_writeable_eq!(short_english.format_i64(3_010_349), "3M");
/// assert_writeable_eq!(short_english.format_i64(-13_132), "-13K");
/// ```
///
/// The result is the nearest such compact number, with halfway cases-
/// rounded towards the number with an even least significant digit.
///
/// ```
/// # use icu::experimental::compactdecimal::CompactDecimalFormatter;
/// # use icu::locale::locale;
/// # use writeable::assert_writeable_eq;
/// #
/// # let short_english = CompactDecimalFormatter::try_new_short(
/// # locale!("en").into(),
/// # Default::default(),
/// # ).unwrap();
/// assert_writeable_eq!(short_english.format_i64(999_499), "999K");
/// assert_writeable_eq!(short_english.format_i64(999_500), "1M");
/// assert_writeable_eq!(short_english.format_i64(1650), "1.6K");
/// assert_writeable_eq!(short_english.format_i64(1750), "1.8K");
/// assert_writeable_eq!(short_english.format_i64(1950), "2K");
/// assert_writeable_eq!(short_english.format_i64(-1_172_700), "-1.2M");
/// ```
pub fn format_i64(&self, value: i64) -> FormattedCompactDecimal<'_> {
let unrounded = FixedDecimal::from(value);
self.format_fixed_decimal(unrounded)
}
/// Formats a floating-point number in compact decimal notation using the default
/// precision settings.
///
/// The result may have a fractional digit only if it is compact and its
/// significand is less than 10. Trailing fractional 0s are omitted, and
/// a sign is shown only for negative values.
///
/// ✨ *Enabled with the `ryu` Cargo feature.*
///
/// # Examples
///
/// ```
/// use icu::experimental::compactdecimal::CompactDecimalFormatter;
/// use icu::locale::locale;
/// use writeable::assert_writeable_eq;
///
/// let short_english = CompactDecimalFormatter::try_new_short(
/// locale!("en").into(),
/// Default::default(),
/// )
/// .unwrap();
///
/// assert_writeable_eq!(short_english.format_f64(0.0).unwrap(), "0");
/// assert_writeable_eq!(short_english.format_f64(2.0).unwrap(), "2");
/// assert_writeable_eq!(short_english.format_f64(843.0).unwrap(), "843");
/// assert_writeable_eq!(short_english.format_f64(2207.0).unwrap(), "2.2K");
/// assert_writeable_eq!(short_english.format_f64(15_127.0).unwrap(), "15K");
/// assert_writeable_eq!(short_english.format_f64(3_010_349.0).unwrap(), "3M");
/// assert_writeable_eq!(short_english.format_f64(-13_132.0).unwrap(), "-13K");
/// ```
///
/// The result is the nearest such compact number, with halfway cases-
/// rounded towards the number with an even least significant digit.
///
/// ```
/// # use icu::experimental::compactdecimal::CompactDecimalFormatter;
/// # use icu::locale::locale;
/// # use writeable::assert_writeable_eq;
/// #
/// # let short_english = CompactDecimalFormatter::try_new_short(
/// # locale!("en").into(),
/// # Default::default(),
/// # ).unwrap();
/// assert_writeable_eq!(short_english.format_f64(999_499.99).unwrap(), "999K");
/// assert_writeable_eq!(short_english.format_f64(999_500.00).unwrap(), "1M");
/// assert_writeable_eq!(short_english.format_f64(1650.0).unwrap(), "1.6K");
/// assert_writeable_eq!(short_english.format_f64(1750.0).unwrap(), "1.8K");
/// assert_writeable_eq!(short_english.format_f64(1950.0).unwrap(), "2K");
/// assert_writeable_eq!(
/// short_english.format_f64(-1_172_700.0).unwrap(),
/// "-1.2M"
/// );
/// ```
#[cfg(feature = "ryu")]
pub fn format_f64(
&self,
value: f64,
) -> Result<FormattedCompactDecimal<'_>, fixed_decimal::LimitError> {
use fixed_decimal::FloatPrecision::RoundTrip;
// NOTE: This first gets the shortest representation of the f64, which
// manifests as double rounding.
let partly_rounded = FixedDecimal::try_from_f64(value, RoundTrip)?;
Ok(self.format_fixed_decimal(partly_rounded))
}
/// Formats a [`FixedDecimal`] by automatically scaling and rounding it.
///
/// The result may have a fractional digit only if it is compact and its
/// significand is less than 10. Trailing fractional 0s are omitted.
///
/// Because the FixedDecimal is mutated before formatting, this function
/// takes ownership of it.
///
/// # Examples
///
/// ```
/// use fixed_decimal::FixedDecimal;
/// use icu::experimental::compactdecimal::CompactDecimalFormatter;
/// use icu::locale::locale;
/// use writeable::assert_writeable_eq;
///
/// let short_english = CompactDecimalFormatter::try_new_short(
/// locale!("en").into(),
/// Default::default(),
/// )
/// .unwrap();
///
/// assert_writeable_eq!(
/// short_english.format_fixed_decimal(FixedDecimal::from(0)),
/// "0"
/// );
/// assert_writeable_eq!(
/// short_english.format_fixed_decimal(FixedDecimal::from(2)),
/// "2"
/// );
/// assert_writeable_eq!(
/// short_english.format_fixed_decimal(FixedDecimal::from(843)),
/// "843"
/// );
/// assert_writeable_eq!(
/// short_english.format_fixed_decimal(FixedDecimal::from(2207)),
/// "2.2K"
/// );
/// assert_writeable_eq!(
/// short_english.format_fixed_decimal(FixedDecimal::from(15127)),
/// "15K"
/// );
/// assert_writeable_eq!(
/// short_english.format_fixed_decimal(FixedDecimal::from(3010349)),
/// "3M"
/// );
/// assert_writeable_eq!(
/// short_english.format_fixed_decimal(FixedDecimal::from(-13132)),
/// "-13K"
/// );
///
/// // The sign display on the FixedDecimal is respected:
/// assert_writeable_eq!(
/// short_english.format_fixed_decimal(
/// FixedDecimal::from(2500)
/// .with_sign_display(fixed_decimal::SignDisplay::ExceptZero)
/// ),
/// "+2.5K"
/// );
/// ```
///
/// The result is the nearest such compact number, with halfway cases-
/// rounded towards the number with an even least significant digit.
///
/// ```
/// # use icu::experimental::compactdecimal::CompactDecimalFormatter;
/// # use icu::locale::locale;
/// # use writeable::assert_writeable_eq;
/// #
/// # let short_english = CompactDecimalFormatter::try_new_short(
/// # locale!("en").into(),
/// # Default::default(),
/// # ).unwrap();
/// assert_writeable_eq!(
/// short_english.format_fixed_decimal("999499.99".parse().unwrap()),
/// "999K"
/// );
/// assert_writeable_eq!(
/// short_english.format_fixed_decimal("999500.00".parse().unwrap()),
/// "1M"
/// );
/// assert_writeable_eq!(
/// short_english.format_fixed_decimal("1650".parse().unwrap()),
/// "1.6K"
/// );
/// assert_writeable_eq!(
/// short_english.format_fixed_decimal("1750".parse().unwrap()),
/// "1.8K"
/// );
/// assert_writeable_eq!(
/// short_english.format_fixed_decimal("1950".parse().unwrap()),
/// "2K"
/// );
/// assert_writeable_eq!(
/// short_english.format_fixed_decimal("-1172700".parse().unwrap()),
/// "-1.2M"
/// );
/// ```
pub fn format_fixed_decimal(&self, value: FixedDecimal) -> FormattedCompactDecimal<'_> {
let log10_type = value.nonzero_magnitude_start();
let (mut plural_map, mut exponent) = self.plural_map_and_exponent_for_magnitude(log10_type);
let mut significand = value.multiplied_pow10(-i16::from(exponent));
// If we have just one digit before the decimal point…
if significand.nonzero_magnitude_start() == 0 {
// …round to one fractional digit…
significand.round(-1);
} else {
// …otherwise, we have at least 2 digits before the decimal point,
// so round to eliminate the fractional part.
significand.round(0);
}
let rounded_magnitude = significand.nonzero_magnitude_start() + i16::from(exponent);
if rounded_magnitude > log10_type {
// We got bumped up a magnitude by rounding.
// This means that `significand` is a power of 10.
let old_exponent = exponent;
// NOTE(egg): We could inline `plural_map_and_exponent_for_magnitude`
// to avoid iterating twice (we only need to look at the next key),
// but this obscures the logic and the map is tiny.
(plural_map, exponent) = self.plural_map_and_exponent_for_magnitude(rounded_magnitude);
significand =
significand.multiplied_pow10(i16::from(old_exponent) - i16::from(exponent));
// There is no need to perform any rounding: `significand`, being
// a power of 10, is as round as it gets, and since `exponent` can
// only have become larger, it is already the correct rounding of
// `unrounded` to the precision we want to show.
}
significand.trim_end();
FormattedCompactDecimal {
formatter: self,
plural_map,
value: Cow::Owned(CompactDecimal::from_significand_and_exponent(
significand,
exponent,
)),
}
}
/// Formats a [`CompactDecimal`] object according to locale data.
///
/// This is an advanced API; prefer using [`Self::format_i64()`] in simple
/// cases.
///
/// Since the caller specifies the exact digits that are displayed, this
/// allows for arbitrarily complex rounding rules.
/// However, contrary to [`FixedDecimalFormatter::format()`], this operation
/// can fail, because the given [`CompactDecimal`] can be inconsistent with
/// the locale data; for instance, if the locale uses lakhs and crores and
/// millions are requested, or vice versa, this function returns an error.
///
/// The given [`CompactDecimal`] should be constructed using
/// [`Self::compact_exponent_for_magnitude()`] on the same
/// [`CompactDecimalFormatter`] object.
/// Specifically, `formatter.format_compact_decimal(n)` requires that `n.exponent()`
/// be equal to `formatter.compact_exponent_for_magnitude(n.significand().nonzero_magnitude_start() + n.exponent())`.
///
/// # Examples
///
/// ```
/// # use icu::experimental::compactdecimal::CompactDecimalFormatter;
/// # use icu::locale::locale;
/// # use writeable::assert_writeable_eq;
/// # use std::str::FromStr;
/// use fixed_decimal::CompactDecimal;
///
/// # let short_french = CompactDecimalFormatter::try_new_short(
/// # locale!("fr").into(),
/// # Default::default(),
/// # ).unwrap();
/// # let long_french = CompactDecimalFormatter::try_new_long(
/// # locale!("fr").into(),
/// # Default::default()
/// # ).unwrap();
/// # let long_bangla = CompactDecimalFormatter::try_new_long(
/// # locale!("bn").into(),
/// # Default::default()
/// # ).unwrap();
/// #
/// let about_a_million = CompactDecimal::from_str("1.20c6").unwrap();
/// let three_million = CompactDecimal::from_str("+3c6").unwrap();
/// let ten_lakhs = CompactDecimal::from_str("10c5").unwrap();
/// # // The following line contains U+00A0 NO-BREAK SPACE.
/// assert_writeable_eq!(
/// short_french
/// .format_compact_decimal(&about_a_million)
/// .unwrap(),
/// "1,20 M"
/// );
/// assert_writeable_eq!(
/// long_french
/// .format_compact_decimal(&about_a_million)
/// .unwrap(),
/// "1,20 million"
/// );
///
/// # // The following line contains U+00A0 NO-BREAK SPACE.
/// assert_writeable_eq!(
/// short_french.format_compact_decimal(&three_million).unwrap(),
/// "+3 M"
/// );
/// assert_writeable_eq!(
/// long_french.format_compact_decimal(&three_million).unwrap(),
/// "+3 millions"
/// );
///
/// assert_writeable_eq!(
/// long_bangla.format_compact_decimal(&ten_lakhs).unwrap(),
/// "১০ লাখ"
/// );
///
/// assert_eq!(
/// long_bangla
/// .format_compact_decimal(&about_a_million)
/// .err()
/// .unwrap()
/// .to_string(),
/// "Expected compact exponent 5 for 10^6, got 6",
/// );
/// assert_eq!(
/// long_french
/// .format_compact_decimal(&ten_lakhs)
/// .err()
/// .unwrap()
/// .to_string(),
/// "Expected compact exponent 6 for 10^6, got 5",
/// );
///
/// /// Some patterns omit the digits; in those cases, the output does not
/// /// contain the sequence of digits specified by the CompactDecimal.
/// let a_thousand = CompactDecimal::from_str("1c3").unwrap();
/// assert_writeable_eq!(
/// long_french.format_compact_decimal(&a_thousand).unwrap(),
/// "mille"
/// );
/// ```
pub fn format_compact_decimal<'l>(
&'l self,
value: &'l CompactDecimal,
) -> Result<FormattedCompactDecimal<'l>, ExponentError> {
let log10_type =
value.significand().nonzero_magnitude_start() + i16::from(value.exponent());
let (plural_map, expected_exponent) =
self.plural_map_and_exponent_for_magnitude(log10_type);
if value.exponent() != expected_exponent {
return Err(ExponentError {
actual: value.exponent(),
expected: expected_exponent,
log10_type,
});
}
Ok(FormattedCompactDecimal {
formatter: self,
plural_map,
value: Cow::Borrowed(value),
})
}
/// Returns the compact decimal exponent that should be used for a number of
/// the given magnitude when using this formatter.
///
/// # Examples
/// ```
/// use icu::experimental::compactdecimal::CompactDecimalFormatter;
/// use icu::locale::locale;
///
/// let [long_french, long_japanese, long_bangla] = [
/// locale!("fr").into(),
/// locale!("ja").into(),
/// locale!("bn").into(),
/// ]
/// .map(|locale| {
/// CompactDecimalFormatter::try_new_long(locale, Default::default())
/// .unwrap()
/// });
/// /// French uses millions.
/// assert_eq!(long_french.compact_exponent_for_magnitude(6), 6);
/// /// Bangla uses lakhs.
/// assert_eq!(long_bangla.compact_exponent_for_magnitude(6), 5);
/// /// Japanese uses myriads.
/// assert_eq!(long_japanese.compact_exponent_for_magnitude(6), 4);
/// ```
pub fn compact_exponent_for_magnitude(&self, magnitude: i16) -> u8 {
let (_, exponent) = self.plural_map_and_exponent_for_magnitude(magnitude);
exponent
}
fn plural_map_and_exponent_for_magnitude(
&self,
magnitude: i16,
) -> (Option<ZeroMap2dCursor<i8, Count, PatternULE>>, u8) {
let plural_map = self
.compact_data
.get()
.patterns
.iter0()
.filter(|cursor| i16::from(*cursor.key0()) <= magnitude)
.last();
let exponent = plural_map
.as_ref()
.and_then(|map| {
map.get1(&Count::Other)
.and_then(|pattern| u8::try_from(pattern.exponent).ok())
})
.unwrap_or(0);
(plural_map, exponent)
}
}
#[cfg(feature = "serde")]
#[cfg(test)]
mod tests {
use super::*;
use icu_decimal::options::GroupingStrategy;
use icu_locale_core::locale;
use writeable::assert_writeable_eq;
#[allow(non_snake_case)]
#[test]
fn test_grouping() {
// https://unicode-org.atlassian.net/browse/ICU-22254
#[derive(Debug)]
struct TestCase<'a> {
short: bool,
options: CompactDecimalFormatterOptions,
expected1T: &'a str,
expected10T: &'a str,
}
let cases = [
TestCase {
short: true,
options: Default::default(),
expected1T: "1000T",
expected10T: "10,000T",
},
TestCase {
short: true,
options: GroupingStrategy::Always.into(),
expected1T: "1,000T",
expected10T: "10,000T",
},
TestCase {
short: true,
options: GroupingStrategy::Never.into(),
expected1T: "1000T",
expected10T: "10000T",
},
TestCase {
short: false,
options: Default::default(),
expected1T: "1000 trillion",
expected10T: "10,000 trillion",
},
TestCase {
short: false,
options: GroupingStrategy::Always.into(),
expected1T: "1,000 trillion",
expected10T: "10,000 trillion",
},
TestCase {
short: false,
options: GroupingStrategy::Never.into(),
expected1T: "1000 trillion",
expected10T: "10000 trillion",
},
];
for case in cases {
let formatter = if case.short {
CompactDecimalFormatter::try_new_short(locale!("en").into(), case.options.clone())
} else {
CompactDecimalFormatter::try_new_long(locale!("en").into(), case.options.clone())
}
.unwrap();
let result1T = formatter.format_i64(1_000_000_000_000_000);
assert_writeable_eq!(result1T, case.expected1T, "{:?}", case);
let result10T = formatter.format_i64(10_000_000_000_000_000);
assert_writeable_eq!(result10T, case.expected10T, "{:?}", case);
}
}
}