clippy_lints/src/types/rc_mutex.rs

   1 use clippy_utils::diagnostics::span_lint;
   2 use clippy_utils::is_ty_param_diagnostic_item;
   3 use if_chain::if_chain;
   4 use rustc_hir::{self as hir, def_id::DefId, QPath};
   5 use rustc_lint::LateContext;
   6 use rustc_span::symbol::sym;
   7
   8 use super::RC_MUTEX;
   9
  10 pub(super) fn check(cx: &LateContext<'_>, hir_ty: &hir::Ty<'_>, qpath: &QPath<'_>, def_id: DefId) -> bool {
  11     if_chain! {
  12         if cx.tcx.is_diagnostic_item(sym::Rc, def_id) ;
  13         if let Some(_) = is_ty_param_diagnostic_item(cx, qpath, sym!(mutex_type)) ;
  14
  15         then{
  16             span_lint(
  17                 cx,
  18                 RC_MUTEX,
  19                 hir_ty.span,
  20                 "found `Rc<Mutex<_>>`. Consider using `Rc<RefCell<_>>` or `Arc<Mutex<_>>` instead",
  21             );
  22             return true;
  23         }
  24     }
  25
  26     false
  27 }