Auto merge of #6424 - Suyash458:master, r=flip1995

Add MSRV to more lints specified in #6097

add MSRV to more lints specified in #6097
add instructions for adding msrv in other lints
update tests

 - [x] `redundant_field_names` requires Rust 1.17 due to suggest feature stablized in that version.
 - [x] `redundant_static_lifetimes` requires Rust 1.17 due to suggest feature stablized in that version.
 - [x] `filter_map_next` requires Rust 1.30 due to suggest `Iterator::find_map`.
 - [x] `checked_conversions` requires Rust 1.34 due to suggest `TryFrom`.
 - [x] `match_like_matches_macro` requires Rust 1.42 due to suggest `matches!`. Addressed in #6201
 - [x] `manual_strip` requires Rust 1.45 due to suggest `str::{strip_prefix, strip_suffix}`. Addressed in #6201
 - [x] `option_as_ref_deref` requires Rust 1.40 due to suggest `Option::{as_deref, as_deref_mut}`. Addressed in #6201
 - [x] `manual_non_exhaustive` requires Rust 1.40 due to suggest `#[non_exhaustive]`. Addressed in #6201
 - [x] `manual_range_contains` requires Rust 1.35 due to suggest `Range*::contains`.
 - [x] `use_self` requires Rust 1.37 due to suggest `Self::Variant on enum`.
 - [x] `mem_replace_with_default` requires Rust 1.40 due to suggest `mem::take`.
 - [x] `map_unwrap_or` requires Rust 1.41 due to suggest `Result::{map_or, map_or_else}`.
 - [x] `missing_const_for_fn` requires Rust 1.46 due to `match/if/loop in const fn` needs that version.

changelog: Add MSRV config to more lints. ^This is now the complete list, AFAWK

clippy_lints/src/checked_conversions.rs

@@ -6,9 +6,12 @@ use rustc_errors::Applicability;
 use rustc_hir::{BinOp, BinOpKind, Expr, ExprKind, QPath, TyKind};
 use rustc_lint::{LateContext, LateLintPass, LintContext};
 use rustc_middle::lint::in_external_macro;
-use rustc_session::{declare_lint_pass, declare_tool_lint};
+use rustc_semver::RustcVersion;
+use rustc_session::{declare_tool_lint, impl_lint_pass};
 
-use crate::utils::{snippet_with_applicability, span_lint_and_sugg, SpanlessEq};
+use crate::utils::{meets_msrv, snippet_with_applicability, span_lint_and_sugg, SpanlessEq};
+
+const CHECKED_CONVERSIONS_MSRV: RustcVersion = RustcVersion::new(1, 34, 0);
 
 declare_clippy_lint! {
     /// **What it does:** Checks for explicit bounds checking when casting.
@@ -39,10 +42,25 @@ declare_clippy_lint! {
     "`try_from` could replace manual bounds checking when casting"
 }
 
-declare_lint_pass!(CheckedConversions => [CHECKED_CONVERSIONS]);
+pub struct CheckedConversions {
+    msrv: Option<RustcVersion>,
+}
+
+impl CheckedConversions {
+    #[must_use]
+    pub fn new(msrv: Option<RustcVersion>) -> Self {
+        Self { msrv }
+    }
+}
+
+impl_lint_pass!(CheckedConversions => [CHECKED_CONVERSIONS]);
 
 impl<'tcx> LateLintPass<'tcx> for CheckedConversions {
     fn check_expr(&mut self, cx: &LateContext<'_>, item: &Expr<'_>) {
+        if !meets_msrv(self.msrv.as_ref(), &CHECKED_CONVERSIONS_MSRV) {
+            return;
+        }
+
         let result = if_chain! {
             if !in_external_macro(cx.sess(), item.span);
             if let ExprKind::Binary(op, ref left, ref right) = &item.kind;
@@ -74,6 +92,8 @@ impl<'tcx> LateLintPass<'tcx> for CheckedConversions {
             }
         }
     }
+
+    extract_msrv_attr!(LateContext);
 }
 
 /// Searches for a single check from unsigned to _ is done

clippy_lints/src/lib.rs

@@ -1005,6 +1005,14 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
     store.register_late_pass(move || box matches::Matches::new(msrv));
     store.register_early_pass(move || box manual_non_exhaustive::ManualNonExhaustive::new(msrv));
     store.register_late_pass(move || box manual_strip::ManualStrip::new(msrv));
+    store.register_early_pass(move || box redundant_static_lifetimes::RedundantStaticLifetimes::new(msrv));
+    store.register_early_pass(move || box redundant_field_names::RedundantFieldNames::new(msrv));
+    store.register_late_pass(move || box checked_conversions::CheckedConversions::new(msrv));
+    store.register_late_pass(move || box mem_replace::MemReplace::new(msrv));
+    store.register_late_pass(move || box ranges::Ranges::new(msrv));
+    store.register_late_pass(move || box use_self::UseSelf::new(msrv));
+    store.register_late_pass(move || box missing_const_for_fn::MissingConstForFn::new(msrv));
+
     store.register_late_pass(|| box size_of_in_element_count::SizeOfInElementCount);
     store.register_late_pass(|| box map_clone::MapClone);
     store.register_late_pass(|| box map_err_ignore::MapErrIgnore);
@@ -1015,7 +1023,6 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
     store.register_late_pass(|| box main_recursion::MainRecursion::default());
     store.register_late_pass(|| box lifetimes::Lifetimes);
     store.register_late_pass(|| box entry::HashMapPass);
-    store.register_late_pass(|| box ranges::Ranges);
     store.register_late_pass(|| box types::Casts);
     let type_complexity_threshold = conf.type_complexity_threshold;
     store.register_late_pass(move || box types::TypeComplexity::new(type_complexity_threshold));
@@ -1060,7 +1067,6 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
     store.register_late_pass(|| box neg_multiply::NegMultiply);
     store.register_late_pass(|| box mem_discriminant::MemDiscriminant);
     store.register_late_pass(|| box mem_forget::MemForget);
-    store.register_late_pass(|| box mem_replace::MemReplace);
     store.register_late_pass(|| box arithmetic::Arithmetic::default());
     store.register_late_pass(|| box assign_ops::AssignOps);
     store.register_late_pass(|| box let_if_seq::LetIfSeq);
@@ -1082,7 +1088,6 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
     store.register_late_pass(move || box pass_by_ref_or_value);
     store.register_late_pass(|| box ref_option_ref::RefOptionRef);
     store.register_late_pass(|| box try_err::TryErr);
-    store.register_late_pass(|| box use_self::UseSelf);
     store.register_late_pass(|| box bytecount::ByteCount);
     store.register_late_pass(|| box infinite_iter::InfiniteIter);
     store.register_late_pass(|| box inline_fn_without_body::InlineFnWithoutBody);
@@ -1108,10 +1113,8 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
     store.register_late_pass(|| box unnecessary_wraps::UnnecessaryWraps);
     store.register_late_pass(|| box types::RefToMut);
     store.register_late_pass(|| box assertions_on_constants::AssertionsOnConstants);
-    store.register_late_pass(|| box missing_const_for_fn::MissingConstForFn);
     store.register_late_pass(|| box transmuting_null::TransmutingNull);
     store.register_late_pass(|| box path_buf_push_overwrite::PathBufPushOverwrite);
-    store.register_late_pass(|| box checked_conversions::CheckedConversions);
     store.register_late_pass(|| box integer_division::IntegerDivision);
     store.register_late_pass(|| box inherent_to_string::InherentToString);
     let max_trait_bounds = conf.max_trait_bounds;
@@ -1140,7 +1143,6 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
     store.register_early_pass(|| box redundant_else::RedundantElse);
     store.register_late_pass(|| box create_dir::CreateDir);
     store.register_early_pass(|| box needless_arbitrary_self_type::NeedlessArbitrarySelfType);
-    store.register_early_pass(|| box redundant_static_lifetimes::RedundantStaticLifetimes);
     store.register_late_pass(|| box cargo_common_metadata::CargoCommonMetadata);
     store.register_late_pass(|| box multiple_crate_versions::MultipleCrateVersions);
     store.register_late_pass(|| box wildcard_dependencies::WildcardDependencies);
@@ -1180,7 +1182,6 @@ pub fn register_plugins(store: &mut rustc_lint::LintStore, sess: &Session, conf:
     store.register_late_pass(|| box mut_mutex_lock::MutMutexLock);
     store.register_late_pass(|| box match_on_vec_items::MatchOnVecItems);
     store.register_late_pass(|| box manual_async_fn::ManualAsyncFn);
-    store.register_early_pass(|| box redundant_field_names::RedundantFieldNames);
     store.register_late_pass(|| box vec_resize_to_zero::VecResizeToZero);
     store.register_late_pass(|| box panic_in_result_fn::PanicInResultFn);
     let single_char_binding_names_threshold = conf.single_char_binding_names_threshold;

clippy_lints/src/mem_replace.rs

@@ -1,13 +1,14 @@
 use crate::utils::{
-    in_macro, match_def_path, match_qpath, paths, snippet, snippet_with_applicability, span_lint_and_help,
+    in_macro, match_def_path, match_qpath, meets_msrv, paths, snippet, snippet_with_applicability, span_lint_and_help,
     span_lint_and_sugg, span_lint_and_then,
 };
 use if_chain::if_chain;
 use rustc_errors::Applicability;
 use rustc_hir::{BorrowKind, Expr, ExprKind, Mutability, QPath};
-use rustc_lint::{LateContext, LateLintPass};
+use rustc_lint::{LateContext, LateLintPass, LintContext};
 use rustc_middle::lint::in_external_macro;
-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::source_map::Span;
 use rustc_span::symbol::sym;
 
@@ -94,7 +95,7 @@ declare_clippy_lint! {
     "replacing a value of type `T` with `T::default()` instead of using `std::mem::take`"
 }
 
-declare_lint_pass!(MemReplace =>
+impl_lint_pass!(MemReplace =>
     [MEM_REPLACE_OPTION_WITH_NONE, MEM_REPLACE_WITH_UNINIT, MEM_REPLACE_WITH_DEFAULT]);
 
 fn check_replace_option_with_none(cx: &LateContext<'_>, src: &Expr<'_>, dest: &Expr<'_>, expr_span: Span) {
@@ -224,6 +225,19 @@ fn check_replace_with_default(cx: &LateContext<'_>, src: &Expr<'_>, dest: &Expr<
     }
 }
 
+const MEM_REPLACE_WITH_DEFAULT_MSRV: RustcVersion = RustcVersion::new(1, 40, 0);
+
+pub struct MemReplace {
+    msrv: Option<RustcVersion>,
+}
+
+impl MemReplace {
+    #[must_use]
+    pub fn new(msrv: Option<RustcVersion>) -> Self {
+        Self { msrv }
+    }
+}
+
 impl<'tcx> LateLintPass<'tcx> for MemReplace {
     fn check_expr(&mut self, cx: &LateContext<'tcx>, expr: &'tcx Expr<'_>) {
         if_chain! {
@@ -236,8 +250,11 @@ impl<'tcx> LateLintPass<'tcx> for MemReplace {
             then {
                 check_replace_option_with_none(cx, src, dest, expr.span);
                 check_replace_with_uninit(cx, src, dest, expr.span);
-                check_replace_with_default(cx, src, dest, expr.span);
+                if meets_msrv(self.msrv.as_ref(), &MEM_REPLACE_WITH_DEFAULT_MSRV) {
+                    check_replace_with_default(cx, src, dest, expr.span);
+                }
             }
         }
     }
+    extract_msrv_attr!(LateContext);
 }

clippy_lints/src/methods/mod.rs

@@ -1487,7 +1487,7 @@ impl<'tcx> LateLintPass<'tcx> for Methods {
             ["expect", ..] => lint_expect(cx, expr, arg_lists[0]),
             ["unwrap_or", "map"] => option_map_unwrap_or::lint(cx, expr, arg_lists[1], arg_lists[0], method_spans[1]),
             ["unwrap_or_else", "map"] => {
-                if !lint_map_unwrap_or_else(cx, expr, arg_lists[1], arg_lists[0]) {
+                if !lint_map_unwrap_or_else(cx, expr, arg_lists[1], arg_lists[0], self.msrv.as_ref()) {
                     unnecessary_lazy_eval::lint(cx, expr, arg_lists[0], "unwrap_or");
                 }
             },
@@ -1509,7 +1509,7 @@ impl<'tcx> LateLintPass<'tcx> for Methods {
             ["next", "iter"] => lint_iter_next(cx, expr, arg_lists[1]),
             ["map", "filter"] => lint_filter_map(cx, expr, arg_lists[1], arg_lists[0]),
             ["map", "filter_map"] => lint_filter_map_map(cx, expr, arg_lists[1], arg_lists[0]),
-            ["next", "filter_map"] => lint_filter_map_next(cx, expr, arg_lists[1]),
+            ["next", "filter_map"] => lint_filter_map_next(cx, expr, arg_lists[1], self.msrv.as_ref()),
             ["map", "find"] => lint_find_map(cx, expr, arg_lists[1], arg_lists[0]),
             ["flat_map", "filter"] => lint_filter_flat_map(cx, expr, arg_lists[1], arg_lists[0]),
             ["flat_map", "filter_map"] => lint_filter_map_flat_map(cx, expr, arg_lists[1], arg_lists[0]),
@@ -2733,14 +2733,20 @@ fn lint_map_flatten<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx hir::Expr<'_>, map
     }
 }
 
+const MAP_UNWRAP_OR_MSRV: RustcVersion = RustcVersion::new(1, 41, 0);
+
 /// lint use of `map().unwrap_or_else()` for `Option`s and `Result`s
 /// Return true if lint triggered
 fn lint_map_unwrap_or_else<'tcx>(
     cx: &LateContext<'tcx>,
     expr: &'tcx hir::Expr<'_>,
     map_args: &'tcx [hir::Expr<'_>],
     unwrap_args: &'tcx [hir::Expr<'_>],
+    msrv: Option<&RustcVersion>,
 ) -> bool {
+    if !meets_msrv(msrv, &MAP_UNWRAP_OR_MSRV) {
+        return false;
+    }
     // lint if the caller of `map()` is an `Option`
     let is_option = is_type_diagnostic_item(cx, cx.typeck_results().expr_ty(&map_args[0]), sym::option_type);
     let is_result = is_type_diagnostic_item(cx, cx.typeck_results().expr_ty(&map_args[0]), sym::result_type);
@@ -2923,9 +2929,20 @@ fn lint_filter_map<'tcx>(
     }
 }
 
+const FILTER_MAP_NEXT_MSRV: RustcVersion = RustcVersion::new(1, 30, 0);
+
 /// lint use of `filter_map().next()` for `Iterators`
-fn lint_filter_map_next<'tcx>(cx: &LateContext<'tcx>, expr: &'tcx hir::Expr<'_>, filter_args: &'tcx [hir::Expr<'_>]) {
+fn lint_filter_map_next<'tcx>(
+    cx: &LateContext<'tcx>,
+    expr: &'tcx hir::Expr<'_>,
+    filter_args: &'tcx [hir::Expr<'_>],
+    msrv: Option<&RustcVersion>,
+) {
     if match_trait_method(cx, expr, &paths::ITERATOR) {
+        if !meets_msrv(msrv, &FILTER_MAP_NEXT_MSRV) {
+            return;
+        }
+
         let msg = "called `filter_map(..).next()` on an `Iterator`. This is more succinctly expressed by calling \
                    `.find_map(..)` instead.";
         let filter_snippet = snippet(cx, filter_args[1].span, "..");

clippy_lints/src/missing_const_for_fn.rs

@@ -1,14 +1,19 @@
 use crate::utils::qualify_min_const_fn::is_min_const_fn;
-use crate::utils::{fn_has_unsatisfiable_preds, has_drop, is_entrypoint_fn, span_lint, trait_ref_of_method};
+use crate::utils::{
+    fn_has_unsatisfiable_preds, has_drop, is_entrypoint_fn, meets_msrv, span_lint, trait_ref_of_method,
+};
 use rustc_hir as hir;
 use rustc_hir::intravisit::FnKind;
 use rustc_hir::{Body, Constness, FnDecl, GenericParamKind, HirId};
-use rustc_lint::{LateContext, LateLintPass};
+use rustc_lint::{LateContext, LateLintPass, LintContext};
 use rustc_middle::lint::in_external_macro;
-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::Span;
 use rustc_typeck::hir_ty_to_ty;
 
+const MISSING_CONST_FOR_FN_MSRV: RustcVersion = RustcVersion::new(1, 37, 0);
+
 declare_clippy_lint! {
     /// **What it does:**
     ///
@@ -69,7 +74,18 @@ declare_clippy_lint! {
     "Lint functions definitions that could be made `const fn`"
 }
 
-declare_lint_pass!(MissingConstForFn => [MISSING_CONST_FOR_FN]);
+impl_lint_pass!(MissingConstForFn => [MISSING_CONST_FOR_FN]);
+
+pub struct MissingConstForFn {
+    msrv: Option<RustcVersion>,
+}
+
+impl MissingConstForFn {
+    #[must_use]
+    pub fn new(msrv: Option<RustcVersion>) -> Self {
+        Self { msrv }
+    }
+}
 
 impl<'tcx> LateLintPass<'tcx> for MissingConstForFn {
     fn check_fn(
@@ -81,6 +97,10 @@ impl<'tcx> LateLintPass<'tcx> for MissingConstForFn {
         span: Span,
         hir_id: HirId,
     ) {
+        if !meets_msrv(self.msrv.as_ref(), &MISSING_CONST_FOR_FN_MSRV) {
+            return;
+        }
+
         let def_id = cx.tcx.hir().local_def_id(hir_id);
 
         if in_external_macro(cx.tcx.sess, span) || is_entrypoint_fn(cx, def_id.to_def_id()) {
@@ -126,6 +146,7 @@ impl<'tcx> LateLintPass<'tcx> for MissingConstForFn {
             span_lint(cx, MISSING_CONST_FOR_FN, span, "this could be a `const fn`");
         }
     }
+    extract_msrv_attr!(LateContext);
 }
 
 /// Returns true if any of the method parameters is a type that implements `Drop`. The method

clippy_lints/src/ranges.rs

@@ -3,18 +3,19 @@ use if_chain::if_chain;
 use rustc_ast::ast::RangeLimits;
 use rustc_errors::Applicability;
 use rustc_hir::{BinOpKind, Expr, ExprKind, PathSegment, QPath};
-use rustc_lint::{LateContext, LateLintPass};
+use rustc_lint::{LateContext, LateLintPass, LintContext};
 use rustc_middle::ty;
-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::source_map::{Span, Spanned};
 use rustc_span::sym;
 use rustc_span::symbol::Ident;
 use std::cmp::Ordering;
 
 use crate::utils::sugg::Sugg;
 use crate::utils::{
-    get_parent_expr, is_integer_const, single_segment_path, snippet, snippet_opt, snippet_with_applicability,
-    span_lint, span_lint_and_sugg, span_lint_and_then,
+    get_parent_expr, is_integer_const, meets_msrv, single_segment_path, snippet, snippet_opt,
+    snippet_with_applicability, span_lint, span_lint_and_sugg, span_lint_and_then,
 };
 use crate::utils::{higher, SpanlessEq};
 
@@ -160,7 +161,20 @@ declare_clippy_lint! {
     "manually reimplementing {`Range`, `RangeInclusive`}`::contains`"
 }
 
-declare_lint_pass!(Ranges => [
+const MANUAL_RANGE_CONTAINS_MSRV: RustcVersion = RustcVersion::new(1, 35, 0);
+
+pub struct Ranges {
+    msrv: Option<RustcVersion>,
+}
+
+impl Ranges {
+    #[must_use]
+    pub fn new(msrv: Option<RustcVersion>) -> Self {
+        Self { msrv }
+    }
+}
+
+impl_lint_pass!(Ranges => [
     RANGE_ZIP_WITH_LEN,
     RANGE_PLUS_ONE,
     RANGE_MINUS_ONE,
@@ -175,7 +189,9 @@ impl<'tcx> LateLintPass<'tcx> for Ranges {
                 check_range_zip_with_len(cx, path, args, expr.span);
             },
             ExprKind::Binary(ref op, ref l, ref r) => {
-                check_possible_range_contains(cx, op.node, l, r, expr.span);
+                if meets_msrv(self.msrv.as_ref(), &MANUAL_RANGE_CONTAINS_MSRV) {
+                    check_possible_range_contains(cx, op.node, l, r, expr.span);
+                }
             },
             _ => {},
         }
@@ -184,6 +200,7 @@ impl<'tcx> LateLintPass<'tcx> for Ranges {
         check_inclusive_range_minus_one(cx, expr);
         check_reversed_empty_range(cx, expr);
     }
+    extract_msrv_attr!(LateContext);
 }
 
 fn check_possible_range_contains(cx: &LateContext<'_>, op: BinOpKind, l: &Expr<'_>, r: &Expr<'_>, span: Span) {