Fix breakage due to rust-lang/rust#60225

6 files changed, 78 insertions, 74 deletions

diff --git a/clippy_lints/src/loops.rs b/clippy_lints/src/loops.rs
index 5fb1a988d14..1f6501f74e7 100644
--- a/clippy_lints/src/loops.rs
+++ b/clippy_lints/src/loops.rs
@@ -676,7 +676,8 @@ fn never_loop_expr(expr: &Expr, main_loop_id: HirId) -> NeverLoopResult {
         | ExprKind::Field(ref e, _)
         | ExprKind::AddrOf(_, ref e)
         | ExprKind::Struct(_, _, Some(ref e))
-        | ExprKind::Repeat(ref e, _) => never_loop_expr(e, main_loop_id),
+        | ExprKind::Repeat(ref e, _)
+        | ExprKind::Use(ref e) => never_loop_expr(e, main_loop_id),
         ExprKind::Array(ref es) | ExprKind::MethodCall(_, _, ref es) | ExprKind::Tup(ref es) => {
             never_loop_expr_all(&mut es.iter(), main_loop_id)
         },
@@ -1458,54 +1459,46 @@ fn check_for_loop_explicit_counter<'a, 'tcx>(
 
     // For each candidate, check the parent block to see if
     // it's initialized to zero at the start of the loop.
-    let map = &cx.tcx.hir();
-    let expr_node_id = expr.hir_id;
-    let parent_scope = map
-        .get_enclosing_scope(expr_node_id)
-        .and_then(|id| map.get_enclosing_scope(id));
-    if let Some(parent_id) = parent_scope {
-        if let Node::Block(block) = map.get_by_hir_id(parent_id) {
-            for (id, _) in visitor.states.iter().filter(|&(_, v)| *v == VarState::IncrOnce) {
-                let mut visitor2 = InitializeVisitor {
-                    cx,
-                    end_expr: expr,
-                    var_id: *id,
-                    state: VarState::IncrOnce,
-                    name: None,
-                    depth: 0,
-                    past_loop: false,
-                };
-                walk_block(&mut visitor2, block);
-
-                if visitor2.state == VarState::Warn {
-                    if let Some(name) = visitor2.name {
-                        let mut applicability = Applicability::MachineApplicable;
-                        span_lint_and_sugg(
-                            cx,
-                            EXPLICIT_COUNTER_LOOP,
-                            expr.span,
-                            &format!("the variable `{}` is used as a loop counter.", name),
-                            "consider using",
-                            format!(
-                                "for ({}, {}) in {}.enumerate()",
-                                name,
-                                snippet_with_applicability(cx, pat.span, "item", &mut applicability),
-                                if higher::range(cx, arg).is_some() {
-                                    format!(
-                                        "({})",
-                                        snippet_with_applicability(cx, arg.span, "_", &mut applicability)
-                                    )
-                                } else {
-                                    format!(
-                                        "{}",
-                                        sugg::Sugg::hir_with_applicability(cx, arg, "_", &mut applicability)
-                                            .maybe_par()
-                                    )
-                                }
-                            ),
-                            applicability,
-                        );
-                    }
+    if let Some(block) = get_enclosing_block(&cx, expr.hir_id) {
+        for (id, _) in visitor.states.iter().filter(|&(_, v)| *v == VarState::IncrOnce) {
+            let mut visitor2 = InitializeVisitor {
+                cx,
+                end_expr: expr,
+                var_id: *id,
+                state: VarState::IncrOnce,
+                name: None,
+                depth: 0,
+                past_loop: false,
+            };
+            walk_block(&mut visitor2, block);
+
+            if visitor2.state == VarState::Warn {
+                if let Some(name) = visitor2.name {
+                    let mut applicability = Applicability::MachineApplicable;
+                    span_lint_and_sugg(
+                        cx,
+                        EXPLICIT_COUNTER_LOOP,
+                        expr.span,
+                        &format!("the variable `{}` is used as a loop counter.", name),
+                        "consider using",
+                        format!(
+                            "for ({}, {}) in {}.enumerate()",
+                            name,
+                            snippet_with_applicability(cx, pat.span, "item", &mut applicability),
+                            if higher::range(cx, arg).is_some() {
+                                format!(
+                                    "({})",
+                                    snippet_with_applicability(cx, arg.span, "_", &mut applicability)
+                                )
+                            } else {
+                                format!(
+                                    "{}",
+                                    sugg::Sugg::hir_with_applicability(cx, arg, "_", &mut applicability).maybe_par()
+                                )
+                            }
+                        ),
+                        applicability,
+                    );
                 }
             }
         }
@@ -2042,7 +2035,7 @@ fn is_simple_break_expr(expr: &Expr) -> bool {
 // To trigger the EXPLICIT_COUNTER_LOOP lint, a variable must be
 // incremented exactly once in the loop body, and initialized to zero
 // at the start of the loop.
-#[derive(PartialEq)]
+#[derive(Debug, PartialEq)]
 enum VarState {
     Initial,  // Not examined yet
     IncrOnce, // Incremented exactly once, may be a loop counter
diff --git a/clippy_lints/src/utils/author.rs b/clippy_lints/src/utils/author.rs
index 4ddae1d01c1..3936473f725 100644
--- a/clippy_lints/src/utils/author.rs
+++ b/clippy_lints/src/utils/author.rs
@@ -495,6 +495,12 @@ impl<'tcx> Visitor<'tcx> for PrintVisitor {
             ExprKind::Err => {
                 println!("Err = {}", current);
             },
+            ExprKind::Use(ref expr) => {
+                let expr_pat = self.next("expr");
+                println!("Use(ref {}) = {};", expr_pat, current);
+                self.current = expr_pat;
+                self.visit_expr(expr);
+            },
         }
     }
 
diff --git a/clippy_lints/src/utils/hir_utils.rs b/clippy_lints/src/utils/hir_utils.rs
index e084ed8224c..71f84d6910f 100644
--- a/clippy_lints/src/utils/hir_utils.rs
+++ b/clippy_lints/src/utils/hir_utils.rs
@@ -156,6 +156,7 @@ impl<'a, 'tcx: 'a> SpanlessEq<'a, 'tcx> {
                     && self.eq_block(lb, rb)
                     && both(ll, rl, |l, r| l.ident.as_str() == r.ident.as_str())
             },
+            (&ExprKind::Use(ref le), &ExprKind::Use(ref re)) => self.eq_expr(le, re),
             _ => false,
         }
     }
@@ -606,6 +607,11 @@ impl<'a, 'tcx: 'a> SpanlessHash<'a, 'tcx> {
                 }
             },
             ExprKind::Err => {},
+            ExprKind::Use(ref e) => {
+                let c: fn(_) -> _ = ExprKind::Use;
+                c.hash(&mut self.s);
+                self.hash_expr(e);
+            },
         }
     }
 
diff --git a/clippy_lints/src/utils/inspector.rs b/clippy_lints/src/utils/inspector.rs
index 72c0b5ce365..02725e51060 100644
--- a/clippy_lints/src/utils/inspector.rs
+++ b/clippy_lints/src/utils/inspector.rs
@@ -330,6 +330,10 @@ fn print_expr(cx: &LateContext<'_, '_>, expr: &hir::Expr, indent: usize) {
         hir::ExprKind::Err => {
             println!("{}Err", ind);
         },
+        hir::ExprKind::Use(ref e) => {
+            println!("{}Use", ind);
+            print_expr(cx, e, indent + 1);
+        },
     }
 }
 
diff --git a/clippy_lints/src/utils/sugg.rs b/clippy_lints/src/utils/sugg.rs
index 72740cee500..acb996a3c9b 100644
--- a/clippy_lints/src/utils/sugg.rs
+++ b/clippy_lints/src/utils/sugg.rs
@@ -115,6 +115,7 @@ impl<'a> Sugg<'a> {
             | hir::ExprKind::Struct(..)
             | hir::ExprKind::Tup(..)
             | hir::ExprKind::While(..)
+            | hir::ExprKind::Use(_)
             | hir::ExprKind::Err => Sugg::NonParen(snippet),
             hir::ExprKind::Assign(..) => Sugg::BinOp(AssocOp::Assign, snippet),
             hir::ExprKind::AssignOp(op, ..) => Sugg::BinOp(hirbinop2assignop(op), snippet),
diff --git a/tests/ui/author/for_loop.stdout b/tests/ui/author/for_loop.stdout
index e223ba1a830..9402705355c 100644
--- a/tests/ui/author/for_loop.stdout
+++ b/tests/ui/author/for_loop.stdout
@@ -1,9 +1,7 @@
 if_chain! {
-    if let ExprKind::Block(ref block) = expr.node;
-    if let StmtKind::Local(ref local) = block.node;
-    if let Some(ref init) = local.init;
-    if let ExprKind::Match(ref expr, ref arms, MatchSource::ForLoopDesugar) = init.node;
-    if let ExprKind::Call(ref func, ref args) = expr.node;
+    if let ExprKind::Use(ref expr) = expr.node;
+    if let ExprKind::Match(ref expr1, ref arms, MatchSource::ForLoopDesugar) = expr.node;
+    if let ExprKind::Call(ref func, ref args) = expr1.node;
     if let ExprKind::Path(ref path) = func.node;
     if match_qpath(path, &["{{root}}", "std", "iter", "IntoIterator", "into_iter"]);
     if args.len() == 1;
@@ -13,12 +11,12 @@ if_chain! {
     // unimplemented: field checks
     if arms.len() == 1;
     if let ExprKind::Loop(ref body, ref label, LoopSource::ForLoop) = arms[0].body.node;
-    if let StmtKind::Local(ref local1) = body.node;
-    if let PatKind::Binding(BindingAnnotation::Mutable, _, name, None) = local1.pat.node;
+    if let StmtKind::Local(ref local) = body.node;
+    if let PatKind::Binding(BindingAnnotation::Mutable, _, name, None) = local.pat.node;
     if name.node.as_str() == "__next";
-    if let StmtKind::Expr(ref e, _) = local1.pat.node
-    if let ExprKind::Match(ref expr1, ref arms1, MatchSource::ForLoopDesugar) = e.node;
-    if let ExprKind::Call(ref func1, ref args1) = expr1.node;
+    if let StmtKind::Expr(ref e, _) = local.pat.node
+    if let ExprKind::Match(ref expr2, ref arms1, MatchSource::ForLoopDesugar) = e.node;
+    if let ExprKind::Call(ref func1, ref args1) = expr2.node;
     if let ExprKind::Path(ref path2) = func1.node;
     if match_qpath(path2, &["{{root}}", "std", "iter", "Iterator", "next"]);
     if args1.len() == 1;
@@ -40,27 +38,23 @@ if_chain! {
     if arms1[1].pats.len() == 1;
     if let PatKind::Path(ref path7) = arms1[1].pats[0].node;
     if match_qpath(path7, &["{{root}}", "std", "option", "Option", "None"]);
-    if let StmtKind::Local(ref local2) = path7.node;
-    if let Some(ref init1) = local2.init;
-    if let ExprKind::Path(ref path8) = init1.node;
+    if let StmtKind::Local(ref local1) = path7.node;
+    if let Some(ref init) = local1.init;
+    if let ExprKind::Path(ref path8) = init.node;
     if match_qpath(path8, &["__next"]);
-    if let PatKind::Binding(BindingAnnotation::Unannotated, _, name1, None) = local2.pat.node;
+    if let PatKind::Binding(BindingAnnotation::Unannotated, _, name1, None) = local1.pat.node;
     if name1.node.as_str() == "y";
-    if let StmtKind::Expr(ref e1, _) = local2.pat.node
-    if let ExprKind::Block(ref block1) = e1.node;
-    if let StmtKind::Local(ref local3) = block1.node;
-    if let Some(ref init2) = local3.init;
-    if let ExprKind::Path(ref path9) = init2.node;
+    if let StmtKind::Expr(ref e1, _) = local1.pat.node
+    if let ExprKind::Block(ref block) = e1.node;
+    if let StmtKind::Local(ref local2) = block.node;
+    if let Some(ref init1) = local2.init;
+    if let ExprKind::Path(ref path9) = init1.node;
     if match_qpath(path9, &["y"]);
-    if let PatKind::Binding(BindingAnnotation::Unannotated, _, name2, None) = local3.pat.node;
+    if let PatKind::Binding(BindingAnnotation::Unannotated, _, name2, None) = local2.pat.node;
     if name2.node.as_str() == "z";
     if arms[0].pats.len() == 1;
     if let PatKind::Binding(BindingAnnotation::Mutable, _, name3, None) = arms[0].pats[0].node;
     if name3.node.as_str() == "iter";
-    if let PatKind::Binding(BindingAnnotation::Unannotated, _, name4, None) = local.pat.node;
-    if name4.node.as_str() == "_result";
-    if let ExprKind::Path(ref path10) = local.pat.node;
-    if match_qpath(path10, &["_result"]);
     then {
         // report your lint here
     }