export default function useLocalizer()

in packages/api/src/hooks/useLocalizer.ts [20:75]
43 lines of code
14 McCabe index (conditional complexity)

export default function useLocalizer({ plural }: { plural?: keyof Plural } = {}) {
  const [globalize] = useLocalizedGlobalize();
  const localizedStrings = useLocalizedStrings();

  return useCallback(
    (id: string | Plural, ...args: [(number | string)?, ...string[]]) => {
      let stringId = id as string;

      if (plural) {
        const pluralId = id as Plural;

        if (!isObject(pluralId)) {
          throw new Error('useLocalizer: Plural string must pass "id" as a map instead of string.');
        } else if (typeof pluralId.other !== 'string') {
          throw new Error('useLocalizer: Plural string must have "id.other" of string.');
        } else if (typeof args[0] !== 'number') {
          throw new Error('useLocalizer: Plural string must have first argument as a number.');
        }

        for (const pluralForm of ['zero', 'one', 'two', 'few', 'many']) {
          // Mitigation through allowlisting.
          // eslint-disable-next-line security/detect-object-injection
          const type = typeof id[pluralForm];

          if (type !== 'string' && type !== 'undefined') {
            throw new Error(`useLocalizer: Plural string must have "id.${pluralForm}" of string or undefined.`);
          }
        }

        const unsupportedPluralForms = Object.keys(id).filter(
          pluralForm => !['zero', 'one', 'two', 'few', 'many', 'other'].includes(pluralForm)
        );

        if (unsupportedPluralForms.length) {
          throw new Error(
            `useLocalizer: Plural string "id" must be either "zero", "one", "two", "few", "many", "other". But not ${unsupportedPluralForms
              .map(pluralForm => `"${pluralForm}"`)
              .join(', ')}.`
          );
        }

        stringId = pluralId[globalize.plural(args[0])] || pluralId.other;
      } else if (typeof id !== 'string') {
        throw new Error('useLocalizer: "id" must be a string.');
      }

      return Object.entries(args).reduce(
        (str, [index, arg]) => str.replace(`$${+index + 1}`, arg),
        // Mitigation through denylisting.
        // eslint-disable-next-line security/detect-object-injection
        isForbiddenPropertyName(stringId) ? '' : localizedStrings[stringId] || DEFAULT_STRINGS[stringId] || ''
      );
    },
    [globalize, localizedStrings, plural]
  );
}