add `tcx` to `fn walk`

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

diff --git a/clippy_lints/src/mut_mut.rs b/clippy_lints/src/mut_mut.rs
index f37f72135033737746c049de7c21436e68fb7d85..610152a217f1e3dac93028b9b41a945f37b92468 100644 (file)
--- a/clippy_lints/src/mut_mut.rs
+++ b/clippy_lints/src/mut_mut.rs
@@ -1,21 +1,25 @@
-use crate::utils::{higher, span_lint};
-use rustc::hir;
-use rustc::hir::intravisit;
-use rustc::lint::{in_external_macro, LateContext, LateLintPass, LintArray, LintContext, LintPass};
-use rustc::ty;
-use rustc::{declare_tool_lint, lint_array};
+use clippy_utils::diagnostics::span_lint;
+use clippy_utils::higher;
+use rustc_hir as hir;
+use rustc_hir::intravisit;
+use rustc_lint::{LateContext, LateLintPass, LintContext};
+use rustc_middle::hir::map::Map;
+use rustc_middle::lint::in_external_macro;
+use rustc_middle::ty;
+use rustc_session::{declare_lint_pass, declare_tool_lint};
 
 declare_clippy_lint! {
-    /// **What it does:** Checks for instances of `mut mut` references.
+    /// ### What it does
+    /// Checks for instances of `mut mut` references.
     ///
-    /// **Why is this bad?** Multiple `mut`s don't add anything meaningful to the
+    /// ### Why is this bad?
+    /// Multiple `mut`s don't add anything meaningful to the
     /// source. This is either a copy'n'paste error, or it shows a fundamental
     /// misunderstanding of references.
     ///
-    /// **Known problems:** None.
-    ///
-    /// **Example:**
+    /// ### Example
     /// ```rust
+    /// # let mut y = 1;
     /// let x = &mut &mut y;
     /// ```
     pub MUT_MUT,
@@ -23,42 +27,33 @@
     "usage of double-mut refs, e.g., `&mut &mut ...`"
 }
 
-#[derive(Copy, Clone)]
-pub struct MutMut;
-
-impl LintPass for MutMut {
-    fn get_lints(&self) -> LintArray {
-        lint_array!(MUT_MUT)
-    }
+declare_lint_pass!(MutMut => [MUT_MUT]);
 
-    fn name(&self) -> &'static str {
-        "MutMut"
-    }
-}
-
-impl<'a, 'tcx> LateLintPass<'a, 'tcx> for MutMut {
-    fn check_block(&mut self, cx: &LateContext<'a, 'tcx>, block: &'tcx hir::Block) {
+impl<'tcx> LateLintPass<'tcx> for MutMut {
+    fn check_block(&mut self, cx: &LateContext<'tcx>, block: &'tcx hir::Block<'_>) {
         intravisit::walk_block(&mut MutVisitor { cx }, block);
     }
 
-    fn check_ty(&mut self, cx: &LateContext<'a, 'tcx>, ty: &'tcx hir::Ty) {
-        use rustc::hir::intravisit::Visitor;
+    fn check_ty(&mut self, cx: &LateContext<'tcx>, ty: &'tcx hir::Ty<'_>) {
+        use rustc_hir::intravisit::Visitor;
 
         MutVisitor { cx }.visit_ty(ty);
     }
 }
 
-pub struct MutVisitor<'a, 'tcx: 'a> {
-    cx: &'a LateContext<'a, 'tcx>,
+pub struct MutVisitor<'a, 'tcx> {
+    cx: &'a LateContext<'tcx>,
 }
 
 impl<'a, 'tcx> intravisit::Visitor<'tcx> for MutVisitor<'a, 'tcx> {
-    fn visit_expr(&mut self, expr: &'tcx hir::Expr) {
+    type Map = Map<'tcx>;
+
+    fn visit_expr(&mut self, expr: &'tcx hir::Expr<'_>) {
         if in_external_macro(self.cx.sess(), expr.span) {
             return;
         }
 
-        if let Some((_, arg, body)) = higher::for_loop(expr) {
+        if let Some(higher::ForLoop { arg, body, .. }) = higher::ForLoop::hir(expr) {
             // A `for` loop lowers to:
             // ```rust
             // match ::std::iter::Iterator::next(&mut iter) {
@@ -67,15 +62,15 @@ fn visit_expr(&mut self, expr: &'tcx hir::Expr) {
             // Let's ignore the generated code.
             intravisit::walk_expr(self, arg);
             intravisit::walk_expr(self, body);
-        } else if let hir::ExprKind::AddrOf(hir::MutMutable, ref e) = expr.node {
-            if let hir::ExprKind::AddrOf(hir::MutMutable, _) = e.node {
+        } else if let hir::ExprKind::AddrOf(hir::BorrowKind::Ref, hir::Mutability::Mut, e) = expr.kind {
+            if let hir::ExprKind::AddrOf(hir::BorrowKind::Ref, hir::Mutability::Mut, _) = e.kind {
                 span_lint(
                     self.cx,
                     MUT_MUT,
                     expr.span,
                     "generally you want to avoid `&mut &mut _` if possible",
                 );
-            } else if let ty::Ref(_, _, hir::MutMutable) = self.cx.tables.expr_ty(e).sty {
+            } else if let ty::Ref(_, _, hir::Mutability::Mut) = self.cx.typeck_results().expr_ty(e).kind() {
                 span_lint(
                     self.cx,
                     MUT_MUT,
@@ -86,21 +81,22 @@ fn visit_expr(&mut self, expr: &'tcx hir::Expr) {
         }
     }
 
-    fn visit_ty(&mut self, ty: &'tcx hir::Ty) {
+    fn visit_ty(&mut self, ty: &'tcx hir::Ty<'_>) {
         if let hir::TyKind::Rptr(
             _,
             hir::MutTy {
-                ty: ref pty,
-                mutbl: hir::MutMutable,
+                ty: pty,
+                mutbl: hir::Mutability::Mut,
             },
-        ) = ty.node
+        ) = ty.kind
         {
             if let hir::TyKind::Rptr(
                 _,
                 hir::MutTy {
-                    mutbl: hir::MutMutable, ..
+                    mutbl: hir::Mutability::Mut,
+                    ..
                 },
-            ) = pty.node
+            ) = pty.kind
             {
                 span_lint(
                     self.cx,
@@ -113,7 +109,7 @@ fn visit_ty(&mut self, ty: &'tcx hir::Ty) {
 
         intravisit::walk_ty(self, ty);
     }
-    fn nested_visit_map<'this>(&'this mut self) -> intravisit::NestedVisitorMap<'this, 'tcx> {
+    fn nested_visit_map(&mut self) -> intravisit::NestedVisitorMap<Self::Map> {
         intravisit::NestedVisitorMap::None
     }
 }