Rollup merge of rust-lang#110955 - fee1-dead-contrib:sus-operation, r=compiler-errors

uplift `clippy::clone_double_ref` as `suspicious_double_ref_op`

Split from rust-lang#109842.

r? ``@compiler-errors``

Author: Dylan-DPC

clippy_lints/src/declared_lints.rs

@@ -313,7 +313,6 @@ pub(crate) static LINTS: &[&crate::LintInfo] = &[
     crate::methods::CHARS_NEXT_CMP_INFO,
     crate::methods::CLEAR_WITH_DRAIN_INFO,
     crate::methods::CLONED_INSTEAD_OF_COPIED_INFO,
-    crate::methods::CLONE_DOUBLE_REF_INFO,
     crate::methods::CLONE_ON_COPY_INFO,
     crate::methods::CLONE_ON_REF_PTR_INFO,
     crate::methods::COLLAPSIBLE_STR_REPLACE_INFO,

clippy_lints/src/methods/clone_on_copy.rs

@@ -1,15 +1,13 @@
-use clippy_utils::diagnostics::{span_lint_and_sugg, span_lint_and_then};
+use clippy_utils::diagnostics::span_lint_and_sugg;
 use clippy_utils::get_parent_node;
 use clippy_utils::source::snippet_with_context;
-use clippy_utils::sugg;
 use clippy_utils::ty::is_copy;
 use rustc_errors::Applicability;
 use rustc_hir::{BindingAnnotation, ByRef, Expr, ExprKind, MatchSource, Node, PatKind, QPath};
 use rustc_lint::LateContext;
 use rustc_middle::ty::{self, adjustment::Adjust, print::with_forced_trimmed_paths};
 use rustc_span::symbol::{sym, Symbol};
 
-use super::CLONE_DOUBLE_REF;
 use super::CLONE_ON_COPY;
 
 /// Checks for the `CLONE_ON_COPY` lint.
@@ -42,41 +40,7 @@ pub(super) fn check(
 
     let ty = cx.typeck_results().expr_ty(expr);
     if let ty::Ref(_, inner, _) = arg_ty.kind() {
-        if let ty::Ref(_, innermost, _) = inner.kind() {
-            span_lint_and_then(
-                cx,
-                CLONE_DOUBLE_REF,
-                expr.span,
-                &with_forced_trimmed_paths!(format!(
-                    "using `clone` on a double-reference; \
-                    this will copy the reference of type `{ty}` instead of cloning the inner type"
-                )),
-                |diag| {
-                    if let Some(snip) = sugg::Sugg::hir_opt(cx, arg) {
-                        let mut ty = innermost;
-                        let mut n = 0;
-                        while let ty::Ref(_, inner, _) = ty.kind() {
-                            ty = inner;
-                            n += 1;
-                        }
-                        let refs = "&".repeat(n + 1);
-                        let derefs = "*".repeat(n);
-                        let explicit = with_forced_trimmed_paths!(format!("<{refs}{ty}>::clone({snip})"));
-                        diag.span_suggestion(
-                            expr.span,
-                            "try dereferencing it",
-                            with_forced_trimmed_paths!(format!("{refs}({derefs}{}).clone()", snip.deref())),
-                            Applicability::MaybeIncorrect,
-                        );
-                        diag.span_suggestion(
-                            expr.span,
-                            "or try being explicit if you are sure, that you want to clone a reference",
-                            explicit,
-                            Applicability::MaybeIncorrect,
-                        );
-                    }
-                },
-            );
+        if let ty::Ref(..) = inner.kind() {
             return; // don't report clone_on_copy
         }
     }

clippy_lints/src/methods/mod.rs

@@ -984,29 +984,6 @@ declare_clippy_lint! {
     "using 'clone' on a ref-counted pointer"
 }
 
-declare_clippy_lint! {
-    /// ### What it does
-    /// Checks for usage of `.clone()` on an `&&T`.
-    ///
-    /// ### Why is this bad?
-    /// Cloning an `&&T` copies the inner `&T`, instead of
-    /// cloning the underlying `T`.
-    ///
-    /// ### Example
-    /// ```rust
-    /// fn main() {
-    ///     let x = vec![1];
-    ///     let y = &&x;
-    ///     let z = y.clone();
-    ///     println!("{:p} {:p}", *y, z); // prints out the same pointer
-    /// }
-    /// ```
-    #[clippy::version = "pre 1.29.0"]
-    pub CLONE_DOUBLE_REF,
-    correctness,
-    "using `clone` on `&&T`"
-}
-
 declare_clippy_lint! {
     /// ### What it does
     /// Checks for usage of `.to_string()` on an `&&T` where
@@ -3258,7 +3235,6 @@ impl_lint_pass!(Methods => [
     CHARS_LAST_CMP,
     CLONE_ON_COPY,
     CLONE_ON_REF_PTR,
-    CLONE_DOUBLE_REF,
     COLLAPSIBLE_STR_REPLACE,
     ITER_OVEREAGER_CLONED,
     CLONED_INSTEAD_OF_COPIED,

clippy_lints/src/renamed_lints.rs

@@ -30,6 +30,7 @@ pub static RENAMED_LINTS: &[(&str, &str)] = &[
     ("clippy::stutter", "clippy::module_name_repetitions"),
     ("clippy::to_string_in_display", "clippy::recursive_format_impl"),
     ("clippy::zero_width_space", "clippy::invisible_characters"),
+    ("clippy::clone_double_ref", "suspicious_double_ref_op"),
     ("clippy::drop_bounds", "drop_bounds"),
     ("clippy::for_loop_over_option", "for_loops_over_fallibles"),
     ("clippy::for_loop_over_result", "for_loops_over_fallibles"),

tests/ui/explicit_deref_methods.fixed

@@ -3,7 +3,7 @@
 #![allow(unused_variables)]
 #![allow(
     clippy::borrow_deref_ref,
-    clippy::clone_double_ref,
+    suspicious_double_ref_op,
     clippy::explicit_auto_deref,
     clippy::needless_borrow,
     clippy::uninlined_format_args

tests/ui/explicit_deref_methods.rs

@@ -3,7 +3,7 @@
 #![allow(unused_variables)]
 #![allow(
     clippy::borrow_deref_ref,
-    clippy::clone_double_ref,
+    suspicious_double_ref_op,
     clippy::explicit_auto_deref,
     clippy::needless_borrow,
     clippy::uninlined_format_args

tests/ui/rename.fixed

@@ -36,6 +36,7 @@
 #![allow(enum_intrinsics_non_enums)]
 #![allow(non_fmt_panics)]
 #![allow(named_arguments_used_positionally)]
+#![allow(suspicious_double_ref_op)]
 #![allow(temporary_cstring_as_ptr)]
 #![allow(unknown_lints)]
 #![allow(unused_labels)]
@@ -67,6 +68,7 @@
 #![warn(clippy::module_name_repetitions)]
 #![warn(clippy::recursive_format_impl)]
 #![warn(clippy::invisible_characters)]
+#![warn(suspicious_double_ref_op)]
 #![warn(drop_bounds)]
 #![warn(for_loops_over_fallibles)]
 #![warn(for_loops_over_fallibles)]

tests/ui/rename.rs

@@ -36,6 +36,7 @@
 #![allow(enum_intrinsics_non_enums)]
 #![allow(non_fmt_panics)]
 #![allow(named_arguments_used_positionally)]
+#![allow(suspicious_double_ref_op)]
 #![allow(temporary_cstring_as_ptr)]
 #![allow(unknown_lints)]
 #![allow(unused_labels)]
@@ -67,6 +68,7 @@
 #![warn(clippy::stutter)]
 #![warn(clippy::to_string_in_display)]
 #![warn(clippy::zero_width_space)]
+#![warn(clippy::clone_double_ref)]
 #![warn(clippy::drop_bounds)]
 #![warn(clippy::for_loop_over_option)]
 #![warn(clippy::for_loop_over_result)]