Auto merge of rust-lang#8280 - xFrednet:8276-map-clone-msrv, r=flip1995

Add `msrv` config for `map_clone`

Just a small PR to have some fun with Clippy and to clear my head a bit 😅

---

changelog: [`map_clone`]: The suggestion takes `msrv` into account
changelog: Track `msrv` attribute for `manual_bits` and `borrow_as_prt`

fixes: rust-lang#8276

Author: bors

clippy_lints/src/borrow_as_ptr.rs

@@ -5,7 +5,7 @@ use clippy_utils::{meets_msrv, msrvs};
 use if_chain::if_chain;
 use rustc_errors::Applicability;
 use rustc_hir::{BorrowKind, Expr, ExprKind, Mutability, TyKind};
-use rustc_lint::{LateContext, LateLintPass};
+use rustc_lint::{LateContext, LateLintPass, LintContext};
 use rustc_semver::RustcVersion;
 use rustc_session::{declare_tool_lint, impl_lint_pass};
 
@@ -94,4 +94,6 @@ impl<'tcx> LateLintPass<'tcx> for BorrowAsPtr {
             }
         }
     }
+
+    extract_msrv_attr!(LateContext);
 }

clippy_lints/src/lib.rs

@@ -581,6 +581,7 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
     store.register_late_pass(move || Box::new(needless_question_mark::NeedlessQuestionMark));
     store.register_late_pass(move || Box::new(casts::Casts::new(msrv)));
     store.register_early_pass(move || Box::new(unnested_or_patterns::UnnestedOrPatterns::new(msrv)));
+    store.register_late_pass(move || Box::new(map_clone::MapClone::new(msrv)));
 
     store.register_late_pass(|| Box::new(size_of_in_element_count::SizeOfInElementCount));
     store.register_late_pass(|| Box::new(same_name_method::SameNameMethod));
@@ -591,7 +592,6 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
             msrv,
         ))
     });
-    store.register_late_pass(|| Box::new(map_clone::MapClone));
     store.register_late_pass(|| Box::new(map_err_ignore::MapErrIgnore));
     store.register_late_pass(|| Box::new(shadow::Shadow::default()));
     store.register_late_pass(|| Box::new(unit_types::UnitTypes));

clippy_lints/src/manual_bits.rs

@@ -4,7 +4,7 @@ use clippy_utils::{match_def_path, meets_msrv, msrvs, paths};
 use rustc_ast::ast::LitKind;
 use rustc_errors::Applicability;
 use rustc_hir::{BinOpKind, Expr, ExprKind, GenericArg, QPath};
-use rustc_lint::{LateContext, LateLintPass};
+use rustc_lint::{LateContext, LateLintPass, LintContext};
 use rustc_middle::ty::{self, Ty};
 use rustc_semver::RustcVersion;
 use rustc_session::{declare_tool_lint, impl_lint_pass};
@@ -72,6 +72,8 @@ impl<'tcx> LateLintPass<'tcx> for ManualBits {
             }
         }
     }
+
+    extract_msrv_attr!(LateContext);
 }
 
 fn get_one_size_of_ty<'tcx>(

clippy_lints/src/map_clone.rs

@@ -1,15 +1,16 @@
 use clippy_utils::diagnostics::span_lint_and_sugg;
 use clippy_utils::source::snippet_with_applicability;
 use clippy_utils::ty::{is_copy, is_type_diagnostic_item};
-use clippy_utils::{is_trait_method, peel_blocks};
+use clippy_utils::{is_trait_method, meets_msrv, msrvs, peel_blocks};
 use if_chain::if_chain;
 use rustc_errors::Applicability;
 use rustc_hir as hir;
-use rustc_lint::{LateContext, LateLintPass};
+use rustc_lint::{LateContext, LateLintPass, LintContext};
 use rustc_middle::mir::Mutability;
 use rustc_middle::ty;
 use rustc_middle::ty::adjustment::Adjust;
-use rustc_session::{declare_lint_pass, declare_tool_lint};
+use rustc_semver::RustcVersion;
+use rustc_session::{declare_tool_lint, impl_lint_pass};
 use rustc_span::symbol::Ident;
 use rustc_span::{sym, Span};
 
@@ -42,7 +43,17 @@ declare_clippy_lint! {
     "using `iterator.map(|x| x.clone())`, or dereferencing closures for `Copy` types"
 }
 
-declare_lint_pass!(MapClone => [MAP_CLONE]);
+pub struct MapClone {
+    msrv: Option<RustcVersion>,
+}
+
+impl_lint_pass!(MapClone => [MAP_CLONE]);
+
+impl MapClone {
+    pub fn new(msrv: Option<RustcVersion>) -> Self {
+        Self { msrv }
+    }
+}
 
 impl<'tcx> LateLintPass<'tcx> for MapClone {
     fn check_expr(&mut self, cx: &LateContext<'_>, e: &hir::Expr<'_>) {
@@ -65,15 +76,15 @@ impl<'tcx> LateLintPass<'tcx> for MapClone {
                         hir::BindingAnnotation::Unannotated, .., name, None
                     ) = inner.kind {
                         if ident_eq(name, closure_expr) {
-                            lint(cx, e.span, args[0].span, true);
+                            self.lint_explicit_closure(cx, e.span, args[0].span, true);
                         }
                     },
                     hir::PatKind::Binding(hir::BindingAnnotation::Unannotated, .., name, None) => {
                         match closure_expr.kind {
                             hir::ExprKind::Unary(hir::UnOp::Deref, inner) => {
                                 if ident_eq(name, inner) {
                                     if let ty::Ref(.., Mutability::Not) = cx.typeck_results().expr_ty(inner).kind() {
-                                        lint(cx, e.span, args[0].span, true);
+                                        self.lint_explicit_closure(cx, e.span, args[0].span, true);
                                     }
                                 }
                             },
@@ -90,7 +101,7 @@ impl<'tcx> LateLintPass<'tcx> for MapClone {
                                     if let ty::Ref(_, ty, mutability) = obj_ty.kind() {
                                         if matches!(mutability, Mutability::Not) {
                                             let copy = is_copy(cx, ty);
-                                            lint(cx, e.span, args[0].span, copy);
+                                            self.lint_explicit_closure(cx, e.span, args[0].span, copy);
                                         }
                                     } else {
                                         lint_needless_cloning(cx, e.span, args[0].span);
@@ -105,6 +116,8 @@ impl<'tcx> LateLintPass<'tcx> for MapClone {
             }
         }
     }
+
+    extract_msrv_attr!(LateContext);
 }
 
 fn ident_eq(name: Ident, path: &hir::Expr<'_>) -> bool {
@@ -127,31 +140,30 @@ fn lint_needless_cloning(cx: &LateContext<'_>, root: Span, receiver: Span) {
     );
 }
 
-fn lint(cx: &LateContext<'_>, replace: Span, root: Span, copied: bool) {
-    let mut applicability = Applicability::MachineApplicable;
-    if copied {
-        span_lint_and_sugg(
-            cx,
-            MAP_CLONE,
-            replace,
-            "you are using an explicit closure for copying elements",
-            "consider calling the dedicated `copied` method",
-            format!(
-                "{}.copied()",
-                snippet_with_applicability(cx, root, "..", &mut applicability)
-            ),
-            applicability,
-        );
-    } else {
+impl MapClone {
+    fn lint_explicit_closure(&self, cx: &LateContext<'_>, replace: Span, root: Span, is_copy: bool) {
+        let mut applicability = Applicability::MachineApplicable;
+        let message = if is_copy {
+            "you are using an explicit closure for copying elements"
+        } else {
+            "you are using an explicit closure for cloning elements"
+        };
+        let sugg_method = if is_copy && meets_msrv(self.msrv.as_ref(), &msrvs::ITERATOR_COPIED) {
+            "copied"
+        } else {
+            "cloned"
+        };
+
         span_lint_and_sugg(
             cx,
             MAP_CLONE,
             replace,
-            "you are using an explicit closure for cloning elements",
-            "consider calling the dedicated `cloned` method",
+            message,
+            &format!("consider calling the dedicated `{}` method", sugg_method),
             format!(
-                "{}.cloned()",
-                snippet_with_applicability(cx, root, "..", &mut applicability)
+                "{}.{}()",
+                snippet_with_applicability(cx, root, "..", &mut applicability),
+                sugg_method,
             ),
             applicability,
         );

clippy_lints/src/utils/conf.rs

@@ -156,7 +156,7 @@ define_Conf! {
     ///
     /// Suppress lints whenever the suggested change would cause breakage for other crates.
     (avoid_breaking_exported_api: bool = true),
-    /// Lint: MANUAL_SPLIT_ONCE, MANUAL_STR_REPEAT, CLONED_INSTEAD_OF_COPIED, REDUNDANT_FIELD_NAMES, REDUNDANT_STATIC_LIFETIMES, FILTER_MAP_NEXT, CHECKED_CONVERSIONS, MANUAL_RANGE_CONTAINS, USE_SELF, MEM_REPLACE_WITH_DEFAULT, MANUAL_NON_EXHAUSTIVE, OPTION_AS_REF_DEREF, MAP_UNWRAP_OR, MATCH_LIKE_MATCHES_MACRO, MANUAL_STRIP, MISSING_CONST_FOR_FN, UNNESTED_OR_PATTERNS, FROM_OVER_INTO, PTR_AS_PTR, IF_THEN_SOME_ELSE_NONE, APPROX_CONSTANT, DEPRECATED_CFG_ATTR, INDEX_REFUTABLE_SLICE.
+    /// Lint: MANUAL_SPLIT_ONCE, MANUAL_STR_REPEAT, CLONED_INSTEAD_OF_COPIED, REDUNDANT_FIELD_NAMES, REDUNDANT_STATIC_LIFETIMES, FILTER_MAP_NEXT, CHECKED_CONVERSIONS, MANUAL_RANGE_CONTAINS, USE_SELF, MEM_REPLACE_WITH_DEFAULT, MANUAL_NON_EXHAUSTIVE, OPTION_AS_REF_DEREF, MAP_UNWRAP_OR, MATCH_LIKE_MATCHES_MACRO, MANUAL_STRIP, MISSING_CONST_FOR_FN, UNNESTED_OR_PATTERNS, FROM_OVER_INTO, PTR_AS_PTR, IF_THEN_SOME_ELSE_NONE, APPROX_CONSTANT, DEPRECATED_CFG_ATTR, INDEX_REFUTABLE_SLICE, MAP_CLONE, BORROW_AS_PTR, MANUAL_BITS.
     ///
     /// The minimum rust version that the project supports
     (msrv: Option<String> = None),

tests/ui-toml/min_rust_version/min_rust_version.rs

@@ -1,6 +1,7 @@
-#![allow(clippy::redundant_clone)]
-#![warn(clippy::manual_non_exhaustive)]
+#![allow(clippy::redundant_clone, clippy::unnecessary_operation)]
+#![warn(clippy::manual_non_exhaustive, clippy::borrow_as_ptr, clippy::manual_bits)]
 
+use std::mem::{size_of, size_of_val};
 use std::ops::Deref;
 
 mod enums {
@@ -68,11 +69,30 @@ fn check_index_refutable_slice() {
     }
 }
 
+fn map_clone_suggest_copied() {
+    // This should still trigger the lint but suggest `cloned()` instead of `copied()`
+    let _: Option<u64> = Some(&16).map(|b| *b);
+}
+
+fn borrow_as_ptr() {
+    let val = 1;
+    let _p = &val as *const i32;
+
+    let mut val_mut = 1;
+    let _p_mut = &mut val_mut as *mut i32;
+}
+
+fn manual_bits() {
+    size_of::<i8>() * 8;
+    size_of_val(&0u32) * 8;
+}
+
 fn main() {
     option_as_ref_deref();
     match_like_matches();
     match_same_arms();
     match_same_arms2();
     manual_strip_msrv();
     check_index_refutable_slice();
+    borrow_as_ptr();
 }

tests/ui-toml/min_rust_version/min_rust_version.stderr

@@ -0,0 +1,10 @@
+error: you are using an explicit closure for copying elements
+  --> $DIR/min_rust_version.rs:74:26
+   |
+LL |     let _: Option<u64> = Some(&16).map(|b| *b);
+   |                          ^^^^^^^^^^^^^^^^^^^^^ help: consider calling the dedicated `cloned` method: `Some(&16).cloned()`
+   |
+   = note: `-D clippy::map-clone` implied by `-D warnings`
+
+error: aborting due to previous error
+