diff options
Diffstat (limited to 'src/tools/clippy/clippy_lints/src/methods/mut_mutex_lock.rs')
-rw-r--r-- | src/tools/clippy/clippy_lints/src/methods/mut_mutex_lock.rs | 31 |
1 files changed, 31 insertions, 0 deletions
diff --git a/src/tools/clippy/clippy_lints/src/methods/mut_mutex_lock.rs b/src/tools/clippy/clippy_lints/src/methods/mut_mutex_lock.rs new file mode 100644 index 000000000..b9593b368 --- /dev/null +++ b/src/tools/clippy/clippy_lints/src/methods/mut_mutex_lock.rs @@ -0,0 +1,31 @@ +use clippy_utils::diagnostics::span_lint_and_sugg; +use clippy_utils::{expr_custom_deref_adjustment, ty::is_type_diagnostic_item}; +use if_chain::if_chain; +use rustc_errors::Applicability; +use rustc_hir::{Expr, Mutability}; +use rustc_lint::LateContext; +use rustc_middle::ty; +use rustc_span::{sym, Span}; + +use super::MUT_MUTEX_LOCK; + +pub(super) fn check<'tcx>(cx: &LateContext<'tcx>, ex: &'tcx Expr<'tcx>, recv: &'tcx Expr<'tcx>, name_span: Span) { + if_chain! { + if matches!(expr_custom_deref_adjustment(cx, recv), None | Some(Mutability::Mut)); + if let ty::Ref(_, _, Mutability::Mut) = cx.typeck_results().expr_ty(recv).kind(); + if let Some(method_id) = cx.typeck_results().type_dependent_def_id(ex.hir_id); + if let Some(impl_id) = cx.tcx.impl_of_method(method_id); + if is_type_diagnostic_item(cx, cx.tcx.type_of(impl_id), sym::Mutex); + then { + span_lint_and_sugg( + cx, + MUT_MUTEX_LOCK, + name_span, + "calling `&mut Mutex::lock` unnecessarily locks an exclusive (mutable) reference", + "change this to", + "get_mut".to_owned(), + Applicability::MaybeIncorrect, + ); + } + } +} |