Function rustdoc::clean::utils::has_doc_flag

pub(crate) fn has_doc_flag(tcx: TyCtxt<'_>, did: DefId, flag: Symbol) -> bool

Checks for the existence of hidden in the attribute below if flag is sym::hidden:

#[doc(hidden)]
pub fn foo() {}

This function exists because it runs on hir::Attributes whereas the other is a clean::Attributes method.