toBe('kevinmcfadden@btinternet.com'); expect(normalize_email_identity('k.e.v.i.n.m.c.f.a.d.d.e.n+two@btinternet.com'))->toBe('kevinmcfadden@btinternet.com'); }); it('returns null for blank or malformed email identities', function (?string $email) { expect(normalize_email_identity($email))->toBeNull(); })->with([ null, '', 'not-an-email', '@example.com', 'local@', ]);