If you are implementing an authentication system that could contain user created passwords, ensure to test with a complex password so that all systems correctly handle symbols:
O'Brien1(*&^%$#@!),._- ?
For the above password, there is a space between the - and the ? - please copy and paste to ensure you capture all symbols.
If the username or passwords could contain diacritics / accent marks, ensure to test with those and provide examples to your project manager.