Merge branch 'macro-use' into HEAD

[rust.git] / clippy_lints / src / mutex_atomic.rs

diff --git a/clippy_lints/src/mutex_atomic.rs b/clippy_lints/src/mutex_atomic.rs
index db2c003b61d73a569f3c76f6630b401c6d331be7..2448cd84d7c7008b35f510015c192f60424e9463 100644 (file)
--- a/clippy_lints/src/mutex_atomic.rs
+++ b/clippy_lints/src/mutex_atomic.rs
@@ -2,11 +2,12 @@
 //!
 //! This lint is **warn** by default
 
-use rustc::lint::{LintPass, LintArray, LateLintPass, LateContext};
-use rustc::ty;
+use rustc::lint::{LateContext, LateLintPass, LintArray, LintPass};
+use rustc::{declare_lint, lint_array};
+use rustc::ty::{self, Ty};
 use rustc::hir::Expr;
 use syntax::ast;
-use utils::{match_type, paths, span_lint};
+use crate::utils::{match_type, paths, span_lint};
 
 /// **What it does:** Checks for usages of `Mutex<X>` where an atomic will do.
 ///
@@ -22,15 +23,17 @@
 /// ```rust
 /// let x = Mutex::new(&y);
 /// ```
-declare_lint! {
+declare_clippy_lint! {
     pub MUTEX_ATOMIC,
-    Warn,
+    perf,
     "using a mutex where an atomic value could be used instead"
 }
 
-/// **What it does:** Checks for usages of `Mutex<X>` where `X` is an integral type.
+/// **What it does:** Checks for usages of `Mutex<X>` where `X` is an integral
+/// type.
 ///
-/// **Why is this bad?** Using a mutex just to make access to a plain integer sequential is
+/// **Why is this bad?** Using a mutex just to make access to a plain integer
+/// sequential is
 /// shooting flies with cannons. `std::atomic::usize` is leaner and faster.
 ///
 /// **Known problems:** This lint cannot detect if the mutex is actually used
@@ -40,9 +43,9 @@
 /// ```rust
 /// let x = Mutex::new(0usize);
 /// ```
-declare_lint! {
+declare_clippy_lint! {
     pub MUTEX_INTEGER,
-    Allow,
+    nursery,
     "using a mutex for an integer type"
 }
 
@@ -54,19 +57,21 @@ fn get_lints(&self) -> LintArray {
 
 pub struct MutexAtomic;
 
-impl LateLintPass for MutexAtomic {
-    fn check_expr(&mut self, cx: &LateContext, expr: &Expr) {
-        let ty = cx.tcx.expr_ty(expr);
-        if let ty::TyStruct(_, subst) = ty.sty {
+impl<'a, 'tcx> LateLintPass<'a, 'tcx> for MutexAtomic {
+    fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr) {
+        let ty = cx.tables.expr_ty(expr);
+        if let ty::TyAdt(_, subst) = ty.sty {
             if match_type(cx, ty, &paths::MUTEX) {
-                let mutex_param = &subst.type_at(0).sty;
+                let mutex_param = subst.type_at(0);
                 if let Some(atomic_name) = get_atomic_name(mutex_param) {
-                    let msg = format!("Consider using an {} instead of a Mutex here. If you just want the locking \
-                                       behaviour and not the internal type, consider using Mutex<()>.",
-                                      atomic_name);
-                    match *mutex_param {
-                        ty::TyUint(t) if t != ast::UintTy::Us => span_lint(cx, MUTEX_INTEGER, expr.span, &msg),
-                        ty::TyInt(t) if t != ast::IntTy::Is => span_lint(cx, MUTEX_INTEGER, expr.span, &msg),
+                    let msg = format!(
+                        "Consider using an {} instead of a Mutex here. If you just want the locking \
+                         behaviour and not the internal type, consider using Mutex<()>.",
+                        atomic_name
+                    );
+                    match mutex_param.sty {
+                        ty::TyUint(t) if t != ast::UintTy::Usize => span_lint(cx, MUTEX_INTEGER, expr.span, &msg),
+                        ty::TyInt(t) if t != ast::IntTy::Isize => span_lint(cx, MUTEX_INTEGER, expr.span, &msg),
                         _ => span_lint(cx, MUTEX_ATOMIC, expr.span, &msg),
                     };
                 }
@@ -75,8 +80,8 @@ fn check_expr(&mut self, cx: &LateContext, expr: &Expr) {
     }
 }
 
-fn get_atomic_name(ty: &ty::TypeVariants) -> Option<(&'static str)> {
-    match *ty {
+fn get_atomic_name(ty: Ty) -> Option<(&'static str)> {
+    match ty.sty {
         ty::TyBool => Some("AtomicBool"),
         ty::TyUint(_) => Some("AtomicUsize"),
         ty::TyInt(_) => Some("AtomicIsize"),