Jest tests to check for missing translations, unused keys and incomplete translation files

i18n.test.js

/* eslint-disable */
import fr from 'config/locales/fr';
import en from 'config/locales/en';

import { exec } from 'child_process';

describe('i18n', () => {
  test('Translations keys are the same for every language', () => {
    const translationKeysEn = iterate(en, '', []);
    const translationKeysFr = iterate(fr, '', []);

    expect(translationKeysFr).toEqual(translationKeysEn);
  });

  test('There should not be unused keys', async () => {
    const translationKeysEn = iterate(en, '', []);

    let everyStringsAreUsed = true;
    for (let i = 0; i < translationKeysEn.length; i += 1) {
      await new Promise(resolve => {
        exec(`grep -rnw './src' -e '${translationKeysEn[i]}'`, (_, stdout) => {
          if (everyStringsAreUsed) everyStringsAreUsed = !(stdout == '');
          if (stdout == '')
            console.warn(`[I18n] Could not find '${translationKeysEn[i]}' in 'src' folder`);
          resolve();
        });
      });
    }
    expect(everyStringsAreUsed).toBeTruthy();
  });

  test('There are no missing keys', done => {
    exec(`grep "I18n.t(.*\'" -ohrw './src' | grep -o "'.*"`, (_, stdout) => {
      const allTranslationsDefined = iterate(en, '', []);
      const allTranslationsUsed = stdout.replace(new RegExp("'", 'g'), '').split('\n');
      allTranslationsUsed.splice(-1, 1);

      for (let i = 0; i < allTranslationsUsed.length; i += 1) {
        expect(allTranslationsDefined).toContainEqual(allTranslationsUsed[i]);
      }
      done();
    });
  });
});

function iterate(obj, stack, array) {
  for (const property in obj) {
    if (obj.hasOwnProperty(property)) {
      if (typeof obj[property] === 'object') {
        iterate(obj[property], `${stack}.${property}`, array);
      } else {
        array.push(`${stack.slice(1)}.${property}`);
      }
    }
  }

  return array;
}

chapeau 👏