src/tools/clippy/clippy_lints/src/types/rc_mutex.rs

   1 use clippy_utils::diagnostics::span_lint_and_help;
   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) ;
  14         then {
  15             span_lint_and_help(
  16                 cx,
  17                 RC_MUTEX,
  18                 hir_ty.span,
  19                 "usage of `Rc<Mutex<_>>`",
  20                 None,
  21                 "consider using `Rc<RefCell<_>>` or `Arc<Mutex<_>>` instead",
  22             );
  23             return true;
  24         }
  25     }
  26
  27     false
  28 }