@mapwhit/style-expressions/lib/expression/definitions/collator.js

Process expressions in map style.

import { Collator } from '../types/collator.js';

import { BooleanType, CollatorType, StringType } from '../types.js';

export { Collator };

export class CollatorExpression {
  constructor(caseSensitive, diacriticSensitive, locale) {
    this.type = CollatorType;
    this.locale = locale;
    this.caseSensitive = caseSensitive;
    this.diacriticSensitive = diacriticSensitive;
  }

  static parse(args, context) {
    if (args.length !== 2) return context.error('Expected one argument.');

    const options = args[1];
    if (typeof options !== 'object' || Array.isArray(options))
      return context.error('Collator options argument must be an object.');

    const caseSensitive = context.parse(
      options['case-sensitive'] === undefined ? false : options['case-sensitive'],
      1,
      BooleanType
    );
    if (!caseSensitive) return null;

    const diacriticSensitive = context.parse(
      options['diacritic-sensitive'] === undefined ? false : options['diacritic-sensitive'],
      1,
      BooleanType
    );
    if (!diacriticSensitive) return null;

    let locale = null;
    if (options.locale) {
      locale = context.parse(options.locale, 1, StringType);
      if (!locale) return null;
    }

    return new CollatorExpression(caseSensitive, diacriticSensitive, locale);
  }

  evaluate(ctx) {
    return new Collator(
      this.caseSensitive.evaluate(ctx),
      this.diacriticSensitive.evaluate(ctx),
      this.locale ? this.locale.evaluate(ctx) : null
    );
  }

  eachChild(fn) {
    fn(this.caseSensitive);
    fn(this.diacriticSensitive);
    if (this.locale) {
      fn(this.locale);
    }
  }

  possibleOutputs() {
    // Technically the set of possible outputs is the combinatoric set of Collators produced
    // by all possibleOutputs of locale/caseSensitive/diacriticSensitive
    // But for the primary use of Collators in comparison operators, we ignore the Collator's
    // possibleOutputs anyway, so we can get away with leaving this undefined for now.
    return [undefined];
  }
}