Disclosure of Diagnose

Hi, I am currently waiting to get a referral for a diagnostic test. However I was wondering regarding having a diagnosed autism on my effectiveness of applying for a citizenship/PR. After some online reading I was met with an impression that some countries won't accept PR if you have some kind of disorder which includes autism. I was wondering if it is required to disclose it or can I choose not to, just like applying for jobs? I am curious as to what my result would be however I feel like if its going to affect my future I might as well just live with it as I have been doing.

Thanks