post_type_supports() returns true when $_wp_post_type_features['post_type']['feature'] is set but false

[linguasite]

Wouldn't it be safer to ask for a true value before returning true?

I had to change a capability manually and did this by directly changing the relevant value to false (without using remove_post_type_support for some reason).
post_type_supports() still returned true then.

wp-includes/post.php line 1031

[nacin]

You should use remove_post_type_support(). Modifying the internal array is not supported. Via add_post_type_support(), it will always equal either true, or an array. We could check for === false there, but I don't think we should need to. It's set, that's what matters. The "true" is just to have a value there (as with pluggable arg checking, it could be more than just "true").

[linguasite]

Thanks nacin, you are absolutely right.
I did some experiments and stumbled upon this phenomenon.

[nacin]

Cheers.