wp-includes/PHPMailer/SMTP.php:925Send an SMTP HELO or EHLO command.
$hellostring$hoststringbool protected function sendHello($hello, $host) { $noerror = $this->sendCommand($hello, $hello . ' ' . $host, 250); $this->helo_rply = $this->last_reply; if ($noerror) { $this->parseHelloFields($hello); } else { $this->server_caps = null; } return $noerror; }Unchanged from 6.7.7 through 7.1.0.
Signature, return type and hooks compared across 5 parsed releases.
src/wp-includes/PHPMailer/SMTP.php, and regenerated for each WordPress release so it tracks the code rather than a snapshot of it.