modify code

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

diff --git a/clippy_lints/src/reference.rs b/clippy_lints/src/reference.rs
index 31e834ac17447eede2fbc85bab58424399370459..811a7bb9c153a273e4d9ff5fbee2252555591a10 100644 (file)
--- a/clippy_lints/src/reference.rs
+++ b/clippy_lints/src/reference.rs
@@ -1,5 +1,4 @@
-use crate::utils::sugg::Sugg;
-use crate::utils::{in_macro, span_lint_and_sugg};
+use clippy_utils::diagnostics::span_lint_and_sugg;
 use clippy_utils::source::{snippet_opt, snippet_with_applicability};
 use if_chain::if_chain;
 use rustc_ast::ast::{Expr, ExprKind, Mutability, UnOp};
@@ -9,15 +8,18 @@
 use rustc_span::BytePos;
 
 declare_clippy_lint! {
-    /// **What it does:** Checks for usage of `*&` and `*&mut` in expressions.
+    /// ### What it does
+    /// Checks for usage of `*&` and `*&mut` in expressions.
     ///
-    /// **Why is this bad?** Immediately dereferencing a reference is no-op and
+    /// ### Why is this bad?
+    /// Immediately dereferencing a reference is no-op and
     /// makes the code less clear.
     ///
-    /// **Known problems:** Multiple dereference/addrof pairs are not handled so
+    /// ### Known problems
+    /// Multiple dereference/addrof pairs are not handled so
     /// the suggested fix for `x = **&&y` is `x = *&y`, which is still incorrect.
     ///
-    /// **Example:**
+    /// ### Example
     /// ```rust,ignore
     /// // Bad
     /// let a = f(*&mut b);
@@ -27,6 +29,7 @@
     /// let a = f(b);
     /// let c = d;
     /// ```
+    #[clippy::version = "pre 1.29.0"]
     pub DEREF_ADDROF,
     complexity,
     "use of `*&` or `*&mut` in an expression"
@@ -46,11 +49,13 @@ fn check_expr(&mut self, cx: &EarlyContext<'_>, e: &Expr) {
         if_chain! {
             if let ExprKind::Unary(UnOp::Deref, ref deref_target) = e.kind;
             if let ExprKind::AddrOf(_, ref mutability, ref addrof_target) = without_parens(deref_target).kind;
-            if !in_macro(addrof_target.span);
+            if deref_target.span.ctxt() == e.span.ctxt();
+            if !addrof_target.span.from_expansion();
             then {
                 let mut applicability = Applicability::MachineApplicable;
                 let sugg = if e.span.from_expansion() {
-                    if let Ok(macro_source) = cx.sess.source_map().span_to_snippet(e.span) {
+                    #[allow(clippy::option_if_let_else)]
+                    if let Some(macro_source) = snippet_opt(cx, e.span) {
                         // Remove leading whitespace from the given span
                         // e.g: ` $visitor` turns into `$visitor`
                         let trim_leading_whitespaces = |span| {
@@ -98,56 +103,3 @@ fn check_expr(&mut self, cx: &EarlyContext<'_>, e: &Expr) {
         }
     }
 }
-
-declare_clippy_lint! {
-    /// **What it does:** Checks for references in expressions that use
-    /// auto dereference.
-    ///
-    /// **Why is this bad?** The reference is a no-op and is automatically
-    /// dereferenced by the compiler and makes the code less clear.
-    ///
-    /// **Example:**
-    /// ```rust
-    /// struct Point(u32, u32);
-    /// let point = Point(30, 20);
-    /// let x = (&point).0;
-    /// ```
-    /// Use instead:
-    /// ```rust
-    /// # struct Point(u32, u32);
-    /// # let point = Point(30, 20);
-    /// let x = point.0;
-    /// ```
-    pub REF_IN_DEREF,
-    complexity,
-    "Use of reference in auto dereference expression."
-}
-
-declare_lint_pass!(RefInDeref => [REF_IN_DEREF]);
-
-impl EarlyLintPass for RefInDeref {
-    fn check_expr(&mut self, cx: &EarlyContext<'_>, e: &Expr) {
-        if_chain! {
-            if let ExprKind::Field(ref object, _) = e.kind;
-            if let ExprKind::Paren(ref parened) = object.kind;
-            if let ExprKind::AddrOf(_, _, ref inner) = parened.kind;
-            then {
-                let applicability = if inner.span.from_expansion() {
-                    Applicability::MaybeIncorrect
-                } else {
-                    Applicability::MachineApplicable
-                };
-                let sugg = Sugg::ast(cx, inner, "_").maybe_par();
-                span_lint_and_sugg(
-                    cx,
-                    REF_IN_DEREF,
-                    object.span,
-                    "creating a reference that is immediately dereferenced",
-                    "try this",
-                    sugg.to_string(),
-                    applicability,
-                );
-            }
-        }
-    }
-}