angular-cn/scripts/cldr/gen_plural_rules.js

180 lines
4.3 KiB
JavaScript

/**
* @license
* Copyright Google Inc. All Rights Reserved.
*
* Use of this source code is governed by an MIT-style license that can be
* found in the LICENSE file at https://angular.io/license
*/
const cldr = require('cldr');
// locale list
const locales = cldr.localeIds;
const langToRule = {};
const ruleToLang = {};
const variants = [];
const localeToVariant = {};
const DEFAULT_RULE = `function anonymous(n\n/**/) {\nreturn"other"\n}`;
const EMPTY_RULE = `function anonymous(n\n/**/) {\n\n}`;
locales.forEach(locale => {
const rule = normalizeRule(cldr.extractPluralRuleFunction(locale).toString());
const lang = getVariantLang(locale, rule);
if (!lang || !rule) {
return;
}
if (!ruleToLang[rule]) {
ruleToLang[rule] = [];
} else if (ruleToLang[rule].indexOf(lang) > -1) {
return;
}
ruleToLang[rule].push(lang);
});
let nextVariantCode = 'a'.charCodeAt(0);
variants.forEach(locale => {
const rule = normalizeRule(cldr.extractPluralRuleFunction(locale).toString());
if (!rule) {
return;
}
let mapTo = null;
if (ruleToLang[rule]) {
mapTo = ruleToLang[rule][0];
localeToVariant[locale] = mapTo;
return;
}
if (!mapTo) {
mapTo = '_' + String.fromCharCode(nextVariantCode++);
langToRule[mapTo] = rule;
ruleToLang[rule] = [mapTo];
localeToVariant[locale] = mapTo;
}
});
console.log(generateCode());
function generateCode() {
checkMapping();
return `
// This is generated code DO NOT MODIFY
// see angular/script/cldr/gen_plural_rules.js
/** @experimental */
export enum Plural {
Zero,
One,
Two,
Few,
Many,
Other,
}
` + generateVars() +
generateRules() + `
}`;
}
function generateRules() {
const codeParts = [`
const lang = locale.split('-')[0].toLowerCase();
switch (lang) {`];
Object.keys(ruleToLang).forEach(rule => {
const langs = ruleToLang[rule];
codeParts.push(...langs.map(l => ` case '${l}': `));
codeParts.push(` ${rule}`);
});
codeParts.push(` // When there is no specification, the default is always other
// see http://cldr.unicode.org/index/cldr-spec/plural-rules
// "other (required—general plural form — also used if the language only has a single form)"
default:
return Plural.Other;
}`);
return codeParts.join('\n');
}
function generateVars(){
return `
/**
* Returns the plural case based on the locale
*
* @experimental
*/
export function getPluralCase(locale: string, nLike: number | string): Plural {
// TODO(vicb): lazy compute
if (typeof nLike === 'string') {
nLike = parseInt(<string>nLike, 10);
}
const n: number = nLike as number;
const nDecimal = n.toString().replace(/^[^.]*\\.?/, '');
const i = Math.floor(Math.abs(n));
const v = nDecimal.length;
const f = parseInt(nDecimal, 10);
const t = parseInt(n.toString().replace(/^[^.]*\\.?|0+$/g,''), 10) || 0;
`;
}
function checkMapping() {
if (localeToVariant.length) {
console.log(`Mapping required:`);
console.log(localeToVariant);
throw new Error('not implemented');
}
}
/**
* If the language rule do not match an existing language rule, flag it as variant and handle it at the end
*/
function getVariantLang(locale, rule) {
let lang = locale.split('_')[0];
if (!langToRule[lang]) {
langToRule[lang] = rule;
return lang;
}
if (langToRule[lang] === rule) {
return lang;
}
variants.push(locale);
return null;
}
function normalizeRule(fn) {
if (fn === DEFAULT_RULE || fn === EMPTY_RULE) return;
return fn
.replace(toRegExp('function anonymous(n\n/**/) {\n'), '')
.replace(toRegExp('var'), 'let')
.replace(toRegExp('"zero"'), ' Plural.Zero')
.replace(toRegExp('"one"'), ' Plural.One')
.replace(toRegExp('"two"'), ' Plural.Two')
.replace(toRegExp('"few"'), ' Plural.Few')
.replace(toRegExp('"many"'), ' Plural.Many')
.replace(toRegExp('"other"'), ' Plural.Other')
.replace(toRegExp('\n}'), '')
.replace(toRegExp('let'), '')
.replace(toRegExp('if(typeof n==="string")n=parseInt(n,10);'), '')
.replace(toRegExp('i=Math.floor(Math.abs(n))'), '')
.replace(/v=n.toString.*?.length/g, '')
.replace(/f=parseInt.*?\|\|0/g, '')
.replace(/t=parseInt.*?\|\|0/g, '')
.replace(/^[ ,;]*/, '')
+ ';';
}
function toRegExp(s) {
return new RegExp(s.replace(/([.*+?^=!:${}()|[\]\/\\])/g, '\\$1'), 'g');
}