masto-fe/app/javascript/mastodon/utils/numbers.js
Sasha Sorokin cb2adaaf9d
Replace shortNumberFormat with <ShortNumber> (#14061)
This commit introduces new utility component - ShortNumber. It should
work almost the same way as original shortNumberFormat function,
though it also localizes units and accepts one more prop - renderer.

Renderer is a function that takes rendered short formatted number
and also ready-to-pluralize number to format display result accordingly.
Ready-to-pluralize number allows to correctly select plural for
compactly notated numbers, respecting thousands and other units.

Issue #12451 accurately describes the issue with using raw numbers
when replacing counter with short version. In short, it doesn't work
with languages such as Russian, that require different plurals,
according to the unit number was compacted to.

All previous usages of shortNumberFormat were replaced with new
function, and as it became unused, it was removed to avoid misleading.
2020-07-06 14:27:32 +02:00

71 lines
1.9 KiB
JavaScript

// @ts-check
export const DECIMAL_UNITS = Object.freeze({
ONE: 1,
TEN: 10,
HUNDRED: Math.pow(10, 2),
THOUSAND: Math.pow(10, 3),
MILLION: Math.pow(10, 6),
BILLION: Math.pow(10, 9),
TRILLION: Math.pow(10, 12),
});
const TEN_THOUSAND = DECIMAL_UNITS.THOUSAND * 10;
const TEN_MILLIONS = DECIMAL_UNITS.MILLION * 10;
/**
* @typedef {[number, number, number]} ShortNumber
* Array of: shorten number, unit of shorten number and maximum fraction digits
*/
/**
* @param {number} sourceNumber Number to convert to short number
* @returns {ShortNumber} Calculated short number
* @example
* shortNumber(5936);
* // => [5.936, 1000, 1]
*/
export function toShortNumber(sourceNumber) {
if (sourceNumber < DECIMAL_UNITS.THOUSAND) {
return [sourceNumber, DECIMAL_UNITS.ONE, 0];
} else if (sourceNumber < DECIMAL_UNITS.MILLION) {
return [
sourceNumber / DECIMAL_UNITS.THOUSAND,
DECIMAL_UNITS.THOUSAND,
sourceNumber < TEN_THOUSAND ? 1 : 0,
];
} else if (sourceNumber < DECIMAL_UNITS.BILLION) {
return [
sourceNumber / DECIMAL_UNITS.MILLION,
DECIMAL_UNITS.MILLION,
sourceNumber < TEN_MILLIONS ? 1 : 0,
];
} else if (sourceNumber < DECIMAL_UNITS.TRILLION) {
return [
sourceNumber / DECIMAL_UNITS.BILLION,
DECIMAL_UNITS.BILLION,
0,
];
}
return [sourceNumber, DECIMAL_UNITS.ONE, 0];
}
/**
* @param {number} sourceNumber Original number that is shortened
* @param {number} division The scale in which short number is displayed
* @returns {number} Number that can be used for plurals when short form used
* @example
* pluralReady(1793, DECIMAL_UNITS.THOUSAND)
* // => 1790
*/
export function pluralReady(sourceNumber, division) {
// eslint-disable-next-line eqeqeq
if (division == null || division < DECIMAL_UNITS.HUNDRED) {
return sourceNumber;
}
let closestScale = division / DECIMAL_UNITS.TEN;
return Math.trunc(sourceNumber / closestScale) * closestScale;
}