Method check

test/requirements.py:1650–1658

(config)

    def _has_pg_extension(self, name):
        def check(config):
            if not against(config, "postgresql"):
                return False
            with config.db.connect() as conn:
                count = conn.exec_driver_sql(
                    "SELECT count(*) FROM pg_extension "
                    "WHERE extname='%s'" % name
                ).scalar()
            return bool(count)

        return only_if(check, "needs %s extension" % name)