ecency-mobile/src/utils/flattenMessages.js

export const flattenMessages = (nestedMessages, prefix = '') => Object.keys(nestedMessages).reduce((messages, key) => {
  const value = nestedMessages[key];
  const prefixedKey = prefix ? `${prefix}.${key}` : key;

  if (typeof value === 'string') {
    messages[prefixedKey] = value;
  } else {
    Object.assign(messages, flattenMessages(value, prefixedKey));
  }

  return messages;
}, {});