X-Git-Url: https://git.lizzy.rs/?a=blobdiff_plain;f=clippy_lints%2Fsrc%2Fimplicit_saturating_sub.rs;h=4069a685ea0a44e9eff0d141fa0c67feba6b769c;hb=dce274024e62a0dc20c639eaa634bf5f01008e78;hp=5207c628987263776989fe329171f7d9072c1d23;hpb=9f6b5de7deaf4dc9e7917370ad09ab85dc23997c;p=rust.git

diff --git a/clippy_lints/src/implicit_saturating_sub.rs b/clippy_lints/src/implicit_saturating_sub.rs
index 5207c628987..4069a685ea0 100644
--- a/clippy_lints/src/implicit_saturating_sub.rs
+++ b/clippy_lints/src/implicit_saturating_sub.rs
@@ -1,9 +1,9 @@
 use clippy_utils::diagnostics::span_lint_and_sugg;
-use clippy_utils::{in_macro, match_qpath, SpanlessEq};
+use clippy_utils::{in_macro, SpanlessEq};
 use if_chain::if_chain;
 use rustc_ast::ast::LitKind;
 use rustc_errors::Applicability;
-use rustc_hir::{BinOpKind, Expr, ExprKind, QPath, StmtKind};
+use rustc_hir::{lang_items::LangItem, BinOpKind, Expr, ExprKind, QPath, StmtKind};
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_session::{declare_lint_pass, declare_tool_lint};
 
@@ -46,21 +46,21 @@ fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>) {
             if let ExprKind::If(cond, then, None) = &expr.kind;
 
             // Check if the conditional expression is a binary operation
-            if let ExprKind::Binary(ref cond_op, ref cond_left, ref cond_right) = cond.kind;
+            if let ExprKind::Binary(ref cond_op, cond_left, cond_right) = cond.kind;
 
             // Ensure that the binary operator is >, != and <
             if BinOpKind::Ne == cond_op.node || BinOpKind::Gt == cond_op.node || BinOpKind::Lt == cond_op.node;
 
             // Check if the true condition block has only one statement
-            if let ExprKind::Block(ref block, _) = then.kind;
+            if let ExprKind::Block(block, _) = then.kind;
             if block.stmts.len() == 1 && block.expr.is_none();
 
             // Check if assign operation is done
-            if let StmtKind::Semi(ref e) = block.stmts[0].kind;
+            if let StmtKind::Semi(e) = block.stmts[0].kind;
             if let Some(target) = subtracts_one(cx, e);
 
             // Extracting out the variable name
-            if let ExprKind::Path(QPath::Resolved(_, ref ares_path)) = target.kind;
+            if let ExprKind::Path(QPath::Resolved(_, ares_path)) = target.kind;
 
             then {
                 // Handle symmetric conditions in the if statement
@@ -87,7 +87,13 @@ fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>) {
 
                 // Get the variable name
                 let var_name = ares_path.segments[0].ident.name.as_str();
-                const INT_TYPES: [&str; 5] = ["i8", "i16", "i32", "i64", "i128"];
+                const INT_TYPES: [LangItem; 5] = [
+                    LangItem::I8,
+                    LangItem::I16,
+                    LangItem::I32,
+                    LangItem::I64,
+                    LangItem::Isize
+                ];
 
                 match cond_num_val.kind {
                     ExprKind::Lit(ref cond_lit) => {
@@ -99,17 +105,30 @@ fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>) {
                             };
                         }
                     },
-                    ExprKind::Path(ref cond_num_path) => {
-                        if INT_TYPES.iter().any(|int_type| match_qpath(cond_num_path, &[int_type, "MIN"])) {
-                            print_lint_and_sugg(cx, &var_name, expr);
-                        };
+                    ExprKind::Path(QPath::TypeRelative(_, name)) => {
+                        if_chain! {
+                            if name.ident.as_str() == "MIN";
+                            if let Some(const_id) = cx.typeck_results().type_dependent_def_id(cond_num_val.hir_id);
+                            if let Some(impl_id) = cx.tcx.impl_of_method(const_id);
+                            let mut int_ids = INT_TYPES.iter().filter_map(|&ty| cx.tcx.lang_items().require(ty).ok());
+                            if int_ids.any(|int_id| int_id == impl_id);
+                            then {
+                                print_lint_and_sugg(cx, &var_name, expr)
+                            }
+                        }
                     },
-                    ExprKind::Call(ref func, _) => {
-                        if let ExprKind::Path(ref cond_num_path) = func.kind {
-                            if INT_TYPES.iter().any(|int_type| match_qpath(cond_num_path, &[int_type, "min_value"])) {
-                                print_lint_and_sugg(cx, &var_name, expr);
+                    ExprKind::Call(func, []) => {
+                        if_chain! {
+                            if let ExprKind::Path(QPath::TypeRelative(_, name)) = func.kind;
+                            if name.ident.as_str() == "min_value";
+                            if let Some(func_id) = cx.typeck_results().type_dependent_def_id(func.hir_id);
+                            if let Some(impl_id) = cx.tcx.impl_of_method(func_id);
+                            let mut int_ids = INT_TYPES.iter().filter_map(|&ty| cx.tcx.lang_items().require(ty).ok());
+                            if int_ids.any(|int_id| int_id == impl_id);
+                            then {
+                                print_lint_and_sugg(cx, &var_name, expr)
                             }
-                        };
+                        }
                     },
                     _ => (),
                 }
@@ -120,7 +139,7 @@ fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>) {
 
 fn subtracts_one<'a>(cx: &LateContext<'_>, expr: &Expr<'a>) -> Option<&'a Expr<'a>> {
     match expr.kind {
-        ExprKind::AssignOp(ref op1, ref target, ref value) => {
+        ExprKind::AssignOp(ref op1, target, value) => {
             if_chain! {
                 if BinOpKind::Sub == op1.node;
                 // Check if literal being subtracted is one
@@ -133,9 +152,9 @@ fn subtracts_one<'a>(cx: &LateContext<'_>, expr: &Expr<'a>) -> Option<&'a Expr<'
                 }
             }
         },
-        ExprKind::Assign(ref target, ref value, _) => {
+        ExprKind::Assign(target, value, _) => {
             if_chain! {
-                if let ExprKind::Binary(ref op1, ref left1, ref right1) = value.kind;
+                if let ExprKind::Binary(ref op1, left1, right1) = value.kind;
                 if BinOpKind::Sub == op1.node;
 
                 if SpanlessEq::new(cx).eq_expr(left1, target);