make-plural-compiler/lib/parser.js

Translates Unicode CLDR pluralization rules to executable JavaScript

"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.Parser = void 0;

class Parser {
  parse(cond) {
    if (cond === 'i = 0 or n = 1') return 'n >= 0 && n <= 1';
    if (cond === 'i = 0,1') return 'n >= 0 && n < 2';

    if (cond === 'i = 1 and v = 0') {
      this.v0 = 1;
      return 'n == 1 && v0';
    }

    return cond.replace(/([^=\s])([!=%]+)([^=\s])/g, '$1 $2 $3').replace(/[ce] (!?)= ([0-9]+)(?:\.\.[0-9]+)?/g, // assume c & e always have the value 0
    (m, noteq, x0) => !noteq === (x0 === '0') ? 'true' : 'false').replace(/^true and |^false or | and true$| or false$/g, '').replace(/([tv]) (!?)= 0/g, (m, sym, noteq) => {
      const sn = sym + '0';
      this[sn] = 1;
      return noteq ? '!' + sn : sn;
    }).replace(/\b[fintv]\b/g, m => {
      this[m] = 1;
      return m;
    }).replace(/([fin]) % (10+)/g, (m, sym, num) => {
      const sn = sym + num;
      this[sn] = 1;
      return sn;
    }).replace(/n10+ = 0/g, 't0 && $&').replace(/(\w+ (!?)= )([0-9.]+,[0-9.,]+)/g, (m, se, noteq, x) => {
      if (m === 'n = 0,1') return '(n == 0 || n == 1)';
      if (noteq) return se + x.split(',').join(' && ' + se);
      return '(' + se + x.split(',').join(' || ' + se) + ')';
    }).replace(/(\w+) (!?)= ([0-9]+)\.\.([0-9]+)/g, (m, sym, noteq, x0, x1) => {
      if (Number(x0) + 1 === Number(x1)) {
        /* istanbul ignore if: noteq is not used in current CLDR */
        if (noteq) return `${sym} != ${x0} && ${sym} != ${x1}`;
        return `(${sym} == ${x0} || ${sym} == ${x1})`;
      }

      if (noteq) return `(${sym} < ${x0} || ${sym} > ${x1})`;

      if (sym === 'n') {
        this.t0 = 1;
        return `(t0 && n >= ${x0} && n <= ${x1})`;
      }

      return `(${sym} >= ${x0} && ${sym} <= ${x1})`;
    }).replace(/ and /g, ' && ').replace(/ or /g, ' || ').replace(/ = /g, ' == ');
  }

  vars() {
    let vars = [];
    if (this.i) vars.push('i = s[0]');
    if (this.f || this.v) vars.push("f = s[1] || ''");
    /* istanbul ignore if: t is not used in current CLDR */

    if (this.t) vars.push("t = (s[1] || '').replace(/0+$/, '')");
    if (this.v) vars.push('v = f.length');
    if (this.v0) vars.push('v0 = !s[1]');
    if (this.t0 || this.n10 || this.n100) vars.push('t0 = Number(s[0]) == n');

    for (let k in this) {
      if (/^.10+$/.test(k)) {
        const k0 = k[0] === 'n' ? 't0 && s[0]' : k[0];
        vars.push(`${k} = ${k0}.slice(-${k.substr(2).length})`);
      }
    }

    if (!vars.length) return '';
    return 'const ' + ["s = String(n).split('.')", ...vars].join(', ');
  }

}

exports.Parser = Parser;