]> git.lizzy.rs Git - rust.git/blobdiff - clippy_lints/src/overflow_check_conditional.rs
ast/hir: Rename field-related structures
[rust.git] / clippy_lints / src / overflow_check_conditional.rs
index 8783055b31eef1ebaa2eeb9c46a5eed8fd05a62e..3c041bac234a589f8034f1dd5ede89db0b6c1c8b 100644 (file)
@@ -1,82 +1,79 @@
-use rustc::lint::*;
-use rustc::hir::*;
 use crate::utils::{span_lint, SpanlessEq};
+use if_chain::if_chain;
+use rustc_hir::{BinOpKind, Expr, ExprKind, QPath};
+use rustc_lint::{LateContext, LateLintPass};
+use rustc_session::{declare_lint_pass, declare_tool_lint};
 
-/// **What it does:** Detects classic underflow/overflow checks.
-///
-/// **Why is this bad?** Most classic C underflow/overflow checks will fail in
-/// Rust. Users can use functions like `overflowing_*` and `wrapping_*` instead.
-///
-/// **Known problems:** None.
-///
-/// **Example:**
-/// ```rust
-/// a + b < a
-/// ```
 declare_clippy_lint! {
+    /// **What it does:** Detects classic underflow/overflow checks.
+    ///
+    /// **Why is this bad?** Most classic C underflow/overflow checks will fail in
+    /// Rust. Users can use functions like `overflowing_*` and `wrapping_*` instead.
+    ///
+    /// **Known problems:** None.
+    ///
+    /// **Example:**
+    /// ```rust
+    /// # let a = 1;
+    /// # let b = 2;
+    /// a + b < a;
+    /// ```
     pub OVERFLOW_CHECK_CONDITIONAL,
     complexity,
     "overflow checks inspired by C which are likely to panic"
 }
 
-#[derive(Copy, Clone)]
-pub struct OverflowCheckConditional;
+declare_lint_pass!(OverflowCheckConditional => [OVERFLOW_CHECK_CONDITIONAL]);
 
-impl LintPass for OverflowCheckConditional {
-    fn get_lints(&self) -> LintArray {
-        lint_array!(OVERFLOW_CHECK_CONDITIONAL)
-    }
-}
-
-impl<'a, 'tcx> LateLintPass<'a, 'tcx> for OverflowCheckConditional {
+impl<'tcx> LateLintPass<'tcx> for OverflowCheckConditional {
     // a + b < a, a > a + b, a < a - b, a - b > a
-    fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr) {
+    fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
         let eq = |l, r| SpanlessEq::new(cx).eq_path_segment(l, r);
         if_chain! {
-            if let ExprKind::Binary(ref op, ref first, ref second) = expr.node;
-            if let ExprKind::Binary(ref op2, ref ident1, ref ident2) = first.node;
-            if let ExprKind::Path(QPath::Resolved(_, ref path1)) = ident1.node;
-            if let ExprKind::Path(QPath::Resolved(_, ref path2)) = ident2.node;
-            if let ExprKind::Path(QPath::Resolved(_, ref path3)) = second.node;
+            if let ExprKind::Binary(ref op, ref first, ref second) = expr.kind;
+            if let ExprKind::Binary(ref op2, ref ident1, ref ident2) = first.kind;
+            if let ExprKind::Path(QPath::Resolved(_, ref path1)) = ident1.kind;
+            if let ExprKind::Path(QPath::Resolved(_, ref path2)) = ident2.kind;
+            if let ExprKind::Path(QPath::Resolved(_, ref path3)) = second.kind;
             if eq(&path1.segments[0], &path3.segments[0]) || eq(&path2.segments[0], &path3.segments[0]);
-            if cx.tables.expr_ty(ident1).is_integral();
-            if cx.tables.expr_ty(ident2).is_integral();
+            if cx.typeck_results().expr_ty(ident1).is_integral();
+            if cx.typeck_results().expr_ty(ident2).is_integral();
             then {
                 if let BinOpKind::Lt = op.node {
                     if let BinOpKind::Add = op2.node {
                         span_lint(cx, OVERFLOW_CHECK_CONDITIONAL, expr.span,
-                            "You are trying to use classic C overflow conditions that will fail in Rust.");
+                            "you are trying to use classic C overflow conditions that will fail in Rust");
                     }
                 }
                 if let BinOpKind::Gt = op.node {
                     if let BinOpKind::Sub = op2.node {
                         span_lint(cx, OVERFLOW_CHECK_CONDITIONAL, expr.span,
-                            "You are trying to use classic C underflow conditions that will fail in Rust.");
+                            "you are trying to use classic C underflow conditions that will fail in Rust");
                     }
                 }
             }
         }
 
         if_chain! {
-            if let ExprKind::Binary(ref op, ref first, ref second) = expr.node;
-            if let ExprKind::Binary(ref op2, ref ident1, ref ident2) = second.node;
-            if let ExprKind::Path(QPath::Resolved(_, ref path1)) = ident1.node;
-            if let ExprKind::Path(QPath::Resolved(_, ref path2)) = ident2.node;
-            if let ExprKind::Path(QPath::Resolved(_, ref path3)) = first.node;
+            if let ExprKind::Binary(ref op, ref first, ref second) = expr.kind;
+            if let ExprKind::Binary(ref op2, ref ident1, ref ident2) = second.kind;
+            if let ExprKind::Path(QPath::Resolved(_, ref path1)) = ident1.kind;
+            if let ExprKind::Path(QPath::Resolved(_, ref path2)) = ident2.kind;
+            if let ExprKind::Path(QPath::Resolved(_, ref path3)) = first.kind;
             if eq(&path1.segments[0], &path3.segments[0]) || eq(&path2.segments[0], &path3.segments[0]);
-            if cx.tables.expr_ty(ident1).is_integral();
-            if cx.tables.expr_ty(ident2).is_integral();
+            if cx.typeck_results().expr_ty(ident1).is_integral();
+            if cx.typeck_results().expr_ty(ident2).is_integral();
             then {
                 if let BinOpKind::Gt = op.node {
                     if let BinOpKind::Add = op2.node {
                         span_lint(cx, OVERFLOW_CHECK_CONDITIONAL, expr.span,
-                            "You are trying to use classic C overflow conditions that will fail in Rust.");
+                            "you are trying to use classic C overflow conditions that will fail in Rust");
                     }
                 }
                 if let BinOpKind::Lt = op.node {
                     if let BinOpKind::Sub = op2.node {
                         span_lint(cx, OVERFLOW_CHECK_CONDITIONAL, expr.span,
-                            "You are trying to use classic C underflow conditions that will fail in Rust.");
+                            "you are trying to use classic C underflow conditions that will fail in Rust");
                     }
                 }
             }