diff --git a/clippy_lints/src/methods/mut_mutex_lock.rs b/clippy_lints/src/methods/mut_mutex_lock.rs index 83e8370f939b..320523aceb67 100644 --- a/clippy_lints/src/methods/mut_mutex_lock.rs +++ b/clippy_lints/src/methods/mut_mutex_lock.rs @@ -1,17 +1,17 @@ use clippy_utils::diagnostics::span_lint_and_sugg; use clippy_utils::expr_custom_deref_adjustment; -use clippy_utils::ty::is_type_diagnostic_item; +use clippy_utils::ty::{is_type_diagnostic_item, peel_mid_ty_refs_is_mutable}; use rustc_errors::Applicability; use rustc_hir::{Expr, Mutability}; use rustc_lint::LateContext; -use rustc_middle::ty; use rustc_span::{Span, sym}; 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 matches!(expr_custom_deref_adjustment(cx, recv), None | Some(Mutability::Mut)) - && let ty::Ref(_, _, Mutability::Mut) = cx.typeck_results().expr_ty(recv).kind() + && let (_, ref_depth, Mutability::Mut) = peel_mid_ty_refs_is_mutable(cx.typeck_results().expr_ty(recv)) + && ref_depth >= 1 && let Some(method_id) = cx.typeck_results().type_dependent_def_id(ex.hir_id) && let Some(impl_id) = cx.tcx.impl_of_method(method_id) && is_type_diagnostic_item(cx, cx.tcx.type_of(impl_id).instantiate_identity(), sym::Mutex) diff --git a/tests/ui/mut_mutex_lock.fixed b/tests/ui/mut_mutex_lock.fixed index bbedbb2bed23..29c5a27cb624 100644 --- a/tests/ui/mut_mutex_lock.fixed +++ b/tests/ui/mut_mutex_lock.fixed @@ -9,6 +9,11 @@ fn mut_mutex_lock() { let mut value = value_mutex.get_mut().unwrap(); *value += 1; + + let mut value_mutex = Mutex::new(42_u8); + let mut_ref_mut_ref_mutex = &mut &mut value_mutex; + let mut value = mut_ref_mut_ref_mutex.get_mut().unwrap(); + *value += 1; } fn no_owned_mutex_lock() { @@ -24,4 +29,11 @@ fn issue9415() { *guard += 1; } +fn mut_ref_ref_mutex_lock() { + let mutex = Mutex::new(42_u8); + let mut_ref_ref_mutex = &mut &mutex; + let mut guard = mut_ref_ref_mutex.lock().unwrap(); + *guard += 1; +} + fn main() {} diff --git a/tests/ui/mut_mutex_lock.rs b/tests/ui/mut_mutex_lock.rs index 74116100e82a..fcdb3ff97dbc 100644 --- a/tests/ui/mut_mutex_lock.rs +++ b/tests/ui/mut_mutex_lock.rs @@ -9,6 +9,11 @@ fn mut_mutex_lock() { let mut value = value_mutex.lock().unwrap(); *value += 1; + + let mut value_mutex = Mutex::new(42_u8); + let mut_ref_mut_ref_mutex = &mut &mut value_mutex; + let mut value = mut_ref_mut_ref_mutex.lock().unwrap(); + *value += 1; } fn no_owned_mutex_lock() { @@ -24,4 +29,11 @@ fn issue9415() { *guard += 1; } +fn mut_ref_ref_mutex_lock() { + let mutex = Mutex::new(42_u8); + let mut_ref_ref_mutex = &mut &mutex; + let mut guard = mut_ref_ref_mutex.lock().unwrap(); + *guard += 1; +} + fn main() {} diff --git a/tests/ui/mut_mutex_lock.stderr b/tests/ui/mut_mutex_lock.stderr index a3d4905c04cb..92601c4c6121 100644 --- a/tests/ui/mut_mutex_lock.stderr +++ b/tests/ui/mut_mutex_lock.stderr @@ -7,5 +7,11 @@ LL | let mut value = value_mutex.lock().unwrap(); = note: `-D clippy::mut-mutex-lock` implied by `-D warnings` = help: to override `-D warnings` add `#[allow(clippy::mut_mutex_lock)]` -error: aborting due to 1 previous error +error: calling `&mut Mutex::lock` unnecessarily locks an exclusive (mutable) reference + --> tests/ui/mut_mutex_lock.rs:15:43 + | +LL | let mut value = mut_ref_mut_ref_mutex.lock().unwrap(); + | ^^^^ help: change this to: `get_mut` + +error: aborting due to 2 previous errors