Auto merge of #4938 - flip1995:rustup, r=flip1995

[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 fb467d886b567963ac7ede2531ab0c0c98bf740d..89865bbaa99e29138d8604c3933853e22c9a2da6 100644 (file)
--- a/clippy_lints/src/mutex_atomic.rs
+++ b/clippy_lints/src/mutex_atomic.rs
@@ -1,75 +1,64 @@
-// Copyright 2014-2018 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
 //! Checks for uses of mutex where an atomic value could be used
 //!
 //! This lint is **warn** by default
 
-use crate::rustc::hir::Expr;
-use crate::rustc::lint::{LateContext, LateLintPass, LintArray, LintPass};
-use crate::rustc::ty::{self, Ty};
-use crate::rustc::{declare_tool_lint, lint_array};
-use crate::syntax::ast;
 use crate::utils::{match_type, paths, span_lint};
+use rustc::declare_lint_pass;
+use rustc::hir::Expr;
+use rustc::lint::{LateContext, LateLintPass, LintArray, LintPass};
+use rustc::ty::{self, Ty};
+use rustc_session::declare_tool_lint;
+use syntax::ast;
 
-/// **What it does:** Checks for usages of `Mutex<X>` where an atomic will do.
-///
-/// **Why is this bad?** Using a mutex just to make access to a plain bool or
-/// reference sequential is shooting flies with cannons.
-/// `std::sync::atomic::AtomicBool` and `std::sync::atomic::AtomicPtr` are leaner and
-/// faster.
-///
-/// **Known problems:** This lint cannot detect if the mutex is actually used
-/// for waiting before a critical section.
-///
-/// **Example:**
-/// ```rust
-/// let x = Mutex::new(&y);
-/// ```
 declare_clippy_lint! {
+    /// **What it does:** Checks for usages of `Mutex<X>` where an atomic will do.
+    ///
+    /// **Why is this bad?** Using a mutex just to make access to a plain bool or
+    /// reference sequential is shooting flies with cannons.
+    /// `std::sync::atomic::AtomicBool` and `std::sync::atomic::AtomicPtr` are leaner and
+    /// faster.
+    ///
+    /// **Known problems:** This lint cannot detect if the mutex is actually used
+    /// for waiting before a critical section.
+    ///
+    /// **Example:**
+    /// ```rust
+    /// # use std::sync::Mutex;
+    /// # let y = 1;
+    /// let x = Mutex::new(&y);
+    /// ```
     pub MUTEX_ATOMIC,
     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.
-///
-/// **Why is this bad?** Using a mutex just to make access to a plain integer
-/// sequential is
-/// shooting flies with cannons. `std::sync::atomic::AtomicUsize` is leaner and faster.
-///
-/// **Known problems:** This lint cannot detect if the mutex is actually used
-/// for waiting before a critical section.
-///
-/// **Example:**
-/// ```rust
-/// let x = Mutex::new(0usize);
-/// ```
 declare_clippy_lint! {
+    /// **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
+    /// shooting flies with cannons. `std::sync::atomic::AtomicUsize` is leaner and faster.
+    ///
+    /// **Known problems:** This lint cannot detect if the mutex is actually used
+    /// for waiting before a critical section.
+    ///
+    /// **Example:**
+    /// ```rust
+    /// # use std::sync::Mutex;
+    /// let x = Mutex::new(0usize);
+    /// ```
     pub MUTEX_INTEGER,
     nursery,
     "using a mutex for an integer type"
 }
 
-impl LintPass for MutexAtomic {
-    fn get_lints(&self) -> LintArray {
-        lint_array!(MUTEX_ATOMIC, MUTEX_INTEGER)
-    }
-}
-
-pub struct MutexAtomic;
+declare_lint_pass!(Mutex => [MUTEX_ATOMIC, MUTEX_INTEGER]);
 
-impl<'a, 'tcx> LateLintPass<'a, 'tcx> for MutexAtomic {
+impl<'a, 'tcx> LateLintPass<'a, 'tcx> for Mutex {
     fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr) {
         let ty = cx.tables.expr_ty(expr);
-        if let ty::Adt(_, subst) = ty.sty {
+        if let ty::Adt(_, subst) = ty.kind {
             if match_type(cx, ty, &paths::MUTEX) {
                 let mutex_param = subst.type_at(0);
                 if let Some(atomic_name) = get_atomic_name(mutex_param) {
@@ -78,7 +67,7 @@ fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr) {
                          behaviour and not the internal type, consider using Mutex<()>.",
                         atomic_name
                     );
-                    match mutex_param.sty {
+                    match mutex_param.kind {
                         ty::Uint(t) if t != ast::UintTy::Usize => span_lint(cx, MUTEX_INTEGER, expr.span, &msg),
                         ty::Int(t) if t != ast::IntTy::Isize => span_lint(cx, MUTEX_INTEGER, expr.span, &msg),
                         _ => span_lint(cx, MUTEX_ATOMIC, expr.span, &msg),
@@ -89,8 +78,8 @@ fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr) {
     }
 }
 
-fn get_atomic_name(ty: Ty<'_>) -> Option<(&'static str)> {
-    match ty.sty {
+fn get_atomic_name(ty: Ty<'_>) -> Option<&'static str> {
+    match ty.kind {
         ty::Bool => Some("AtomicBool"),
         ty::Uint(_) => Some("AtomicUsize"),
         ty::Int(_) => Some("AtomicIsize"),