title: Is it a good idea to add locale-specific tests in the PostgreSQL regression suite?
body: <p>I am working on a feature related to locales, For testing this, I need to run a few SQL queries by using different locale settings. For Example.</p>
  
  <pre><code>SET lc_messages to 'en_US.UTF-8';
  -- some sql queries;
  SET lc_messages to 'fr_FR.UTF-8';
  -- some sql queries;
  </code></pre>
  
  <p>On my Linux machine, it is working but we can't always expect this set or any(except C or POSIX)  locales will be available on other platforms. Is there a way around this problem?</p>