separate the receiver from arguments in HIR under /clippy

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

diff --git a/clippy_lints/src/ptr_offset_with_cast.rs b/clippy_lints/src/ptr_offset_with_cast.rs
index 93bd3b57ad7ec036c6893f04441fe664d91a1cb9..4dc65da3ea1fd9fd8227823a0ce416c6c573a466 100644 (file)
--- a/clippy_lints/src/ptr_offset_with_cast.rs
+++ b/clippy_lints/src/ptr_offset_with_cast.rs
@@ -1,20 +1,22 @@
-use crate::utils;
+use clippy_utils::diagnostics::{span_lint, span_lint_and_sugg};
+use clippy_utils::source::snippet_opt;
 use rustc_errors::Applicability;
 use rustc_hir::{Expr, ExprKind};
 use rustc_lint::{LateContext, LateLintPass};
 use rustc_session::{declare_lint_pass, declare_tool_lint};
+use rustc_span::sym;
 use std::fmt;
 
 declare_clippy_lint! {
-    /// **What it does:** Checks for usage of the `offset` pointer method with a `usize` casted to an
+    /// ### What it does
+    /// Checks for usage of the `offset` pointer method with a `usize` casted to an
     /// `isize`.
     ///
-    /// **Why is this bad?** If we’re always increasing the pointer address, we can avoid the numeric
+    /// ### Why is this bad?
+    /// If we’re always increasing the pointer address, we can avoid the numeric
     /// cast by using the `add` method instead.
     ///
-    /// **Known problems:** None
-    ///
-    /// **Example:**
+    /// ### Example
     /// ```rust
     /// let vec = vec![b'a', b'b', b'c'];
     /// let ptr = vec.as_ptr();
@@ -36,6 +38,7 @@
     ///     ptr.add(offset);
     /// }
     /// ```
+    #[clippy::version = "1.30.0"]
     pub PTR_OFFSET_WITH_CAST,
     complexity,
     "unneeded pointer offset cast"
@@ -43,8 +46,8 @@
 
 declare_lint_pass!(PtrOffsetWithCast => [PTR_OFFSET_WITH_CAST]);
 
-impl<'a, 'tcx> LateLintPass<'a, 'tcx> for PtrOffsetWithCast {
-    fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr<'_>) {
+impl<'tcx> LateLintPass<'tcx> for PtrOffsetWithCast {
+    fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
         // Check if the expressions is a ptr.offset or ptr.wrapping_offset method call
         let (receiver_expr, arg_expr, method) = match expr_as_ptr_offset_call(cx, expr) {
             Some(call_arg) => call_arg,
@@ -59,7 +62,7 @@ fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr<'_>) {
 
         let msg = format!("use of `{}` with a `usize` casted to an `isize`", method);
         if let Some(sugg) = build_suggestion(cx, method, receiver_expr, cast_lhs_expr) {
-            utils::span_lint_and_sugg(
+            span_lint_and_sugg(
                 cx,
                 PTR_OFFSET_WITH_CAST,
                 expr.span,
@@ -69,15 +72,15 @@ fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr<'_>) {
                 Applicability::MachineApplicable,
             );
         } else {
-            utils::span_lint(cx, PTR_OFFSET_WITH_CAST, expr.span, &msg);
+            span_lint(cx, PTR_OFFSET_WITH_CAST, expr.span, &msg);
         }
     }
 }
 
 // If the given expression is a cast from a usize, return the lhs of the cast
-fn expr_as_cast_from_usize<'a, 'tcx>(cx: &LateContext<'a, 'tcx>, expr: &'tcx Expr<'tcx>) -> Option<&'tcx Expr<'tcx>> {
-    if let ExprKind::Cast(ref cast_lhs_expr, _) = expr.kind {
-        if is_expr_ty_usize(cx, &cast_lhs_expr) {
+fn expr_as_cast_from_usize<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx Expr<'tcx>) -> Option<&'tcx Expr<'tcx>> {
+    if let ExprKind::Cast(cast_lhs_expr, _) = expr.kind {
+        if is_expr_ty_usize(cx, cast_lhs_expr) {
             return Some(cast_lhs_expr);
         }
     }
@@ -86,17 +89,17 @@ fn expr_as_cast_from_usize<'a, 'tcx>(cx: &LateContext<'a, 'tcx>, expr: &'tcx Exp
 
 // If the given expression is a ptr::offset  or ptr::wrapping_offset method call, return the
 // receiver, the arg of the method call, and the method.
-fn expr_as_ptr_offset_call<'a, 'tcx>(
-    cx: &LateContext<'a, 'tcx>,
+fn expr_as_ptr_offset_call<'tcx>(
+    cx: &LateContext<'tcx>,
     expr: &'tcx Expr<'_>,
 ) -> Option<(&'tcx Expr<'tcx>, &'tcx Expr<'tcx>, Method)> {
-    if let ExprKind::MethodCall(ref path_segment, _, ref args) = expr.kind {
-        if is_expr_ty_raw_ptr(cx, &args[0]) {
-            if path_segment.ident.name == sym!(offset) {
-                return Some((&args[0], &args[1], Method::Offset));
+    if let ExprKind::MethodCall(path_segment, arg_0, [arg_1, ..], _) = &expr.kind {
+        if is_expr_ty_raw_ptr(cx, arg_0) {
+            if path_segment.ident.name == sym::offset {
+                return Some((arg_0, arg_1, Method::Offset));
             }
             if path_segment.ident.name == sym!(wrapping_offset) {
-                return Some((&args[0], &args[1], Method::WrappingOffset));
+                return Some((arg_0, arg_1, Method::WrappingOffset));
             }
         }
     }
@@ -104,23 +107,23 @@ fn expr_as_ptr_offset_call<'a, 'tcx>(
 }
 
 // Is the type of the expression a usize?
-fn is_expr_ty_usize<'a, 'tcx>(cx: &LateContext<'a, 'tcx>, expr: &Expr<'_>) -> bool {
-    cx.tables.expr_ty(expr) == cx.tcx.types.usize
+fn is_expr_ty_usize<'tcx>(cx: &LateContext<'tcx>, expr: &Expr<'_>) -> bool {
+    cx.typeck_results().expr_ty(expr) == cx.tcx.types.usize
 }
 
 // Is the type of the expression a raw pointer?
-fn is_expr_ty_raw_ptr<'a, 'tcx>(cx: &LateContext<'a, 'tcx>, expr: &Expr<'_>) -> bool {
-    cx.tables.expr_ty(expr).is_unsafe_ptr()
+fn is_expr_ty_raw_ptr<'tcx>(cx: &LateContext<'tcx>, expr: &Expr<'_>) -> bool {
+    cx.typeck_results().expr_ty(expr).is_unsafe_ptr()
 }
 
-fn build_suggestion<'a, 'tcx>(
-    cx: &LateContext<'a, 'tcx>,
+fn build_suggestion<'tcx>(
+    cx: &LateContext<'tcx>,
     method: Method,
     receiver_expr: &Expr<'_>,
     cast_lhs_expr: &Expr<'_>,
 ) -> Option<String> {
-    let receiver = utils::snippet_opt(cx, receiver_expr.span)?;
-    let cast_lhs = utils::snippet_opt(cx, cast_lhs_expr.span)?;
+    let receiver = snippet_opt(cx, receiver_expr.span)?;
+    let cast_lhs = snippet_opt(cx, cast_lhs_expr.span)?;
     Some(format!("{}.{}({})", receiver, method.suggestion(), cast_lhs))
 }