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Auto merge of #9743 - smoelius:improve-needless-lifetimes, r=Alexendoo 

Improve `needless_lifetimes`

This PR makes the following improvements to `needless_lifetimes`.

* It fixes the following false negative, where `foo` is flagged but `bar` is not:
  ```rust
    fn foo<'a>(x: &'a u8, y: &'_ u8) {}

    fn bar<'a>(x: &'a u8, y: &'_ u8, z: &'_ u8) {}
  ```
* It flags more cases, generally. Previously, `needless_borrow` required *all* lifetimes to be used only once. With the changes, individual lifetimes are flagged for being used only once, even if not all lifetimes are.
* Finally, it tries to produce more clear error messages.

changelog: fix `needless_lifetimes` false negative involving functions with multiple unnamed lifetimes
changelog: in `needless_lifetimes`, flag individual lifetimes used only once, rather than require all lifetimes to be used only once
changelog: in `needless_lifetimes`, emit "replace with `'_`" warnings only when applicable, and point to a generic argument
This commit is contained in:
bors 2022-11-01 00:25:30 +00:00
parent 37d338c1ef c0d928561c
commit 7600535511
50 changed files with 458 additions and 214 deletions
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2
clippy_lints/src/booleans.rs
View File

@ -481,7 +481,7 @@ impl<'a, 'tcx> Visitor<'tcx> for NonminimalBoolVisitor<'a, 'tcx> {
}
}
fn implements_ord<'tcx>(cx: &LateContext<'tcx>, expr: &Expr<'_>) -> bool {
fn implements_ord(cx: &LateContext<'_>, expr: &Expr<'_>) -> bool {
let ty = cx.typeck_results().expr_ty(expr);
cx.tcx
.get_diagnostic_item(sym::Ord)

4
clippy_lints/src/dereference.rs
View File

@ -1232,8 +1232,8 @@ fn is_mixed_projection_predicate<'tcx>(
}
}
fn referent_used_exactly_once<'a, 'tcx>(
cx: &'a LateContext<'tcx>,
fn referent_used_exactly_once<'tcx>(
cx: &LateContext<'tcx>,
possible_borrowers: &mut Vec<(LocalDefId, PossibleBorrowerMap<'tcx, 'tcx>)>,
reference: &Expr<'tcx>,
) -> bool {

6
clippy_lints/src/doc.rs
View File

@ -336,8 +336,8 @@ impl<'tcx> LateLintPass<'tcx> for DocMarkdown {
}
}
fn lint_for_missing_headers<'tcx>(
cx: &LateContext<'tcx>,
fn lint_for_missing_headers(
cx: &LateContext<'_>,
def_id: LocalDefId,
span: impl Into<MultiSpan> + Copy,
sig: &hir::FnSig<'_>,
@ -467,7 +467,7 @@ struct DocHeaders {
panics: bool,
}
fn check_attrs<'a>(cx: &LateContext<'_>, valid_idents: &FxHashSet<String>, attrs: &'a [Attribute]) -> DocHeaders {
fn check_attrs(cx: &LateContext<'_>, valid_idents: &FxHashSet<String>, attrs: &[Attribute]) -> DocHeaders {
use pulldown_cmark::{BrokenLink, CowStr, Options};
/// We don't want the parser to choke on intra doc links. Since we don't
/// actually care about rendering them, just pretend that all broken links are

2
clippy_lints/src/fallible_impl_from.rs
View File

@ -64,7 +64,7 @@ impl<'tcx> LateLintPass<'tcx> for FallibleImplFrom {
}
}
fn lint_impl_body<'tcx>(cx: &LateContext<'tcx>, impl_span: Span, impl_items: &[hir::ImplItemRef]) {
fn lint_impl_body(cx: &LateContext<'_>, impl_span: Span, impl_items: &[hir::ImplItemRef]) {
use rustc_hir::intravisit::{self, Visitor};
use rustc_hir::{Expr, ImplItemKind};

4
clippy_lints/src/implicit_hasher.rs
View File

@ -66,8 +66,8 @@ impl<'tcx> LateLintPass<'tcx> for ImplicitHasher {
fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx Item<'_>) {
use rustc_span::BytePos;
fn suggestion<'tcx>(
cx: &LateContext<'tcx>,
fn suggestion(
cx: &LateContext<'_>,
diag: &mut Diagnostic,
generics_span: Span,
generics_suggestion_span: Span,

4
clippy_lints/src/index_refutable_slice.rs
View File

@ -207,8 +207,8 @@ impl SliceLintInformation {
}
}
fn filter_lintable_slices<'a, 'tcx>(
cx: &'a LateContext<'tcx>,
fn filter_lintable_slices<'tcx>(
cx: &LateContext<'tcx>,
slice_lint_info: FxIndexMap<hir::HirId, SliceLintInformation>,
max_suggested_slice: u64,
scope: &'tcx hir::Expr<'tcx>,

6
clippy_lints/src/indexing_slicing.rs
View File

@ -171,11 +171,7 @@ impl<'tcx> LateLintPass<'tcx> for IndexingSlicing {
/// Returns a tuple of options with the start and end (exclusive) values of
/// the range. If the start or end is not constant, None is returned.
fn to_const_range<'tcx>(
cx: &LateContext<'tcx>,
range: higher::Range<'_>,
array_size: u128,
) -> (Option<u128>, Option<u128>) {
fn to_const_range(cx: &LateContext<'_>, range: higher::Range<'_>, array_size: u128) -> (Option<u128>, Option<u128>) {
let s = range
.start
.map(|expr| constant(cx, cx.typeck_results(), expr).map(|(c, _)| c));

2
clippy_lints/src/invalid_upcast_comparisons.rs
View File

@ -38,7 +38,7 @@ declare_clippy_lint! {
declare_lint_pass!(InvalidUpcastComparisons => [INVALID_UPCAST_COMPARISONS]);
fn numeric_cast_precast_bounds<'a>(cx: &LateContext<'_>, expr: &'a Expr<'_>) -> Option<(FullInt, FullInt)> {
fn numeric_cast_precast_bounds(cx: &LateContext<'_>, expr: &Expr<'_>) -> Option<(FullInt, FullInt)> {
if let ExprKind::Cast(cast_exp, _) = expr.kind {
let pre_cast_ty = cx.typeck_results().expr_ty(cast_exp);
let cast_ty = cx.typeck_results().expr_ty(expr);

133
clippy_lints/src/lifetimes.rs
View File

@ -1,4 +1,4 @@
use clippy_utils::diagnostics::span_lint;
use clippy_utils::diagnostics::{span_lint, span_lint_and_then};
use clippy_utils::trait_ref_of_method;
use rustc_data_structures::fx::{FxHashMap, FxHashSet};
use rustc_hir::intravisit::nested_filter::{self as hir_nested_filter, NestedFilter};
@ -151,6 +151,7 @@ fn check_fn_inner<'tcx>(
.params
.iter()
.filter(|param| matches!(param.kind, GenericParamKind::Type { .. }));
for typ in types {
for pred in generics.bounds_for_param(cx.tcx.hir().local_def_id(typ.hir_id)) {
if pred.origin == PredicateOrigin::WhereClause {
@ -187,15 +188,30 @@ fn check_fn_inner<'tcx>(
}
}
}
if could_use_elision(cx, decl, body, trait_sig, generics.params) {
span_lint(
if let Some(elidable_lts) = could_use_elision(cx, decl, body, trait_sig, generics.params) {
let lts = elidable_lts
.iter()
// In principle, the result of the call to `Node::ident` could be `unwrap`ped, as `DefId` should refer to a
// `Node::GenericParam`.
.filter_map(|&(def_id, _)| cx.tcx.hir().get_by_def_id(def_id).ident())
.map(|ident| ident.to_string())
.collect::<Vec<_>>()
.join(", ");
span_lint_and_then(
cx,
NEEDLESS_LIFETIMES,
span.with_hi(decl.output.span().hi()),
"explicit lifetimes given in parameter types where they could be elided \
(or replaced with `'_` if needed by type declaration)",
&format!("the following explicit lifetimes could be elided: {lts}"),
|diag| {
if let Some(span) = elidable_lts.iter().find_map(|&(_, span)| span) {
diag.span_help(span, "replace with `'_` in generic arguments such as here");
}
},
);
}
if report_extra_lifetimes {
self::report_extra_lifetimes(cx, decl, generics);
}
@ -226,7 +242,7 @@ fn could_use_elision<'tcx>(
body: Option<BodyId>,
trait_sig: Option<&[Ident]>,
named_generics: &'tcx [GenericParam<'_>],
) -> bool {
) -> Option<Vec<(LocalDefId, Option<Span>)>> {
// There are two scenarios where elision works:
// * no output references, all input references have different LT
// * output references, exactly one input reference with same LT
@ -253,7 +269,7 @@ fn could_use_elision<'tcx>(
}
if input_visitor.abort() || output_visitor.abort() {
return false;
return None;
}
let input_lts = input_visitor.lts;
@ -261,7 +277,7 @@ fn could_use_elision<'tcx>(
if let Some(trait_sig) = trait_sig {
if explicit_self_type(cx, func, trait_sig.first().copied()) {
return false;
return None;
}
}
@ -270,7 +286,7 @@ fn could_use_elision<'tcx>(
let first_ident = body.params.first().and_then(|param| param.pat.simple_ident());
if explicit_self_type(cx, func, first_ident) {
return false;
return None;
}
let mut checker = BodyLifetimeChecker {
@ -278,14 +294,14 @@ fn could_use_elision<'tcx>(
};
checker.visit_expr(body.value);
if checker.lifetimes_used_in_body {
return false;
return None;
}
}
// check for lifetimes from higher scopes
for lt in input_lts.iter().chain(output_lts.iter()) {
if !allowed_lts.contains(lt) {
return false;
return None;
}
}
@ -301,48 +317,45 @@ fn could_use_elision<'tcx>(
for lt in input_visitor.nested_elision_site_lts {
if let RefLt::Named(def_id) = lt {
if allowed_lts.contains(&cx.tcx.item_name(def_id.to_def_id())) {
return false;
return None;
}
}
}
for lt in output_visitor.nested_elision_site_lts {
if let RefLt::Named(def_id) = lt {
if allowed_lts.contains(&cx.tcx.item_name(def_id.to_def_id())) {
return false;
return None;
}
}
}
}
// no input lifetimes? easy case!
if input_lts.is_empty() {
false
} else if output_lts.is_empty() {
// no output lifetimes, check distinctness of input lifetimes
// only unnamed and static, ok
let unnamed_and_static = input_lts.iter().all(|lt| *lt == RefLt::Unnamed || *lt == RefLt::Static);
if unnamed_and_static {
return false;
}
// we have no output reference, so we only need all distinct lifetimes
input_lts.len() == unique_lifetimes(&input_lts)
} else {
// we have output references, so we need one input reference,
// and all output lifetimes must be the same
if unique_lifetimes(&output_lts) > 1 {
return false;
}
if input_lts.len() == 1 {
match (&input_lts[0], &output_lts[0]) {
(&RefLt::Named(n1), &RefLt::Named(n2)) if n1 == n2 => true,
(&RefLt::Named(_), &RefLt::Unnamed) => true,
_ => false, /* already elided, different named lifetimes
* or something static going on */
// A lifetime can be newly elided if:
// - It occurs only once among the inputs.
// - If there are multiple input lifetimes, then the newly elided lifetime does not occur among the
// outputs (because eliding such an lifetime would create an ambiguity).
let elidable_lts = named_lifetime_occurrences(&input_lts)
.into_iter()
.filter_map(|(def_id, occurrences)| {
if occurrences == 1 && (input_lts.len() == 1 || !output_lts.contains(&RefLt::Named(def_id))) {
Some((
def_id,
input_visitor
.lifetime_generic_arg_spans
.get(&def_id)
.or_else(|| output_visitor.lifetime_generic_arg_spans.get(&def_id))
.copied(),
))
} else {
None
}
} else {
false
}
})
.collect::<Vec<_>>();
if elidable_lts.is_empty() {
None
} else {
Some(elidable_lts)
}
}
@ -358,10 +371,24 @@ fn allowed_lts_from(tcx: TyCtxt<'_>, named_generics: &[GenericParam<'_>]) -> FxH
allowed_lts
}
/// Number of unique lifetimes in the given vector.
/// Number of times each named lifetime occurs in the given slice. Returns a vector to preserve
/// relative order.
#[must_use]
fn unique_lifetimes(lts: &[RefLt]) -> usize {
lts.iter().collect::<FxHashSet<_>>().len()
fn named_lifetime_occurrences(lts: &[RefLt]) -> Vec<(LocalDefId, usize)> {
let mut occurrences = Vec::new();
for lt in lts {
if let &RefLt::Named(curr_def_id) = lt {
if let Some(pair) = occurrences
.iter_mut()
.find(|(prev_def_id, _)| *prev_def_id == curr_def_id)
{
pair.1 += 1;
} else {
occurrences.push((curr_def_id, 1));
}
}
}
occurrences
}
const CLOSURE_TRAIT_BOUNDS: [LangItem; 3] = [LangItem::Fn, LangItem::FnMut, LangItem::FnOnce];
@ -370,6 +397,7 @@ const CLOSURE_TRAIT_BOUNDS: [LangItem; 3] = [LangItem::Fn, LangItem::FnMut, Lang
struct RefVisitor<'a, 'tcx> {
cx: &'a LateContext<'tcx>,
lts: Vec<RefLt>,
lifetime_generic_arg_spans: FxHashMap<LocalDefId, Span>,
nested_elision_site_lts: Vec<RefLt>,
unelided_trait_object_lifetime: bool,
}
@ -379,6 +407,7 @@ impl<'a, 'tcx> RefVisitor<'a, 'tcx> {
Self {
cx,
lts: Vec::new(),
lifetime_generic_arg_spans: FxHashMap::default(),
nested_elision_site_lts: Vec::new(),
unelided_trait_object_lifetime: false,
}
@ -472,6 +501,22 @@ impl<'a, 'tcx> Visitor<'tcx> for RefVisitor<'a, 'tcx> {
_ => walk_ty(self, ty),
}
}
fn visit_generic_arg(&mut self, generic_arg: &'tcx GenericArg<'tcx>) {
if let GenericArg::Lifetime(l) = generic_arg
&& let LifetimeName::Param(def_id, _) = l.name
{
self.lifetime_generic_arg_spans.entry(def_id).or_insert(l.span);
}
// Replace with `walk_generic_arg` if/when https://github.com/rust-lang/rust/pull/103692 lands.
// walk_generic_arg(self, generic_arg);
match generic_arg {
GenericArg::Lifetime(lt) => self.visit_lifetime(lt),
GenericArg::Type(ty) => self.visit_ty(ty),
GenericArg::Const(ct) => self.visit_anon_const(&ct.value),
GenericArg::Infer(inf) => self.visit_infer(inf),
}
}
}
/// Are any lifetimes mentioned in the `where` clause? If so, we don't try to

4
clippy_lints/src/loops/mut_range_bound.rs
View File

@ -52,8 +52,8 @@ fn check_for_mutability(cx: &LateContext<'_>, bound: &Expr<'_>) -> Option<HirId>
None
}
fn check_for_mutation<'tcx>(
cx: &LateContext<'tcx>,
fn check_for_mutation(
cx: &LateContext<'_>,
body: &Expr<'_>,
bound_id_start: Option<HirId>,
bound_id_end: Option<HirId>,

2
clippy_lints/src/map_unit_fn.rs
View File

@ -119,7 +119,7 @@ fn is_unit_expression(cx: &LateContext<'_>, expr: &hir::Expr<'_>) -> bool {
/// semicolons, which causes problems when generating a suggestion. Given an
/// expression that evaluates to '()' or '!', recursively remove useless braces
/// and semi-colons until is suitable for including in the suggestion template
fn reduce_unit_expression<'a>(cx: &LateContext<'_>, expr: &'a hir::Expr<'_>) -> Option<Span> {
fn reduce_unit_expression(cx: &LateContext<'_>, expr: &hir::Expr<'_>) -> Option<Span> {
if !is_unit_expression(cx, expr) {
return None;
}

2
clippy_lints/src/matches/manual_filter.rs
View File

@ -62,7 +62,7 @@ fn peels_blocks_incl_unsafe<'a>(expr: &'a Expr<'a>) -> &'a Expr<'a> {
// <expr>
// }
// Returns true if <expr> resolves to `Some(x)`, `false` otherwise
fn is_some_expr<'tcx>(cx: &LateContext<'_>, target: HirId, ctxt: SyntaxContext, expr: &'tcx Expr<'_>) -> bool {
fn is_some_expr(cx: &LateContext<'_>, target: HirId, ctxt: SyntaxContext, expr: &Expr<'_>) -> bool {
if let Some(inner_expr) = peels_blocks_incl_unsafe_opt(expr) {
// there can be not statements in the block as they would be removed when switching to `.filter`
if let ExprKind::Call(callee, [arg]) = inner_expr.kind {

6
clippy_lints/src/matches/significant_drop_in_scrutinee.rs
View File

@ -83,8 +83,8 @@ fn set_diagnostic<'tcx>(diag: &mut Diagnostic, cx: &LateContext<'tcx>, expr: &'t
/// If the expression is an `ExprKind::Match`, check if the scrutinee has a significant drop that
/// may have a surprising lifetime.
fn has_significant_drop_in_scrutinee<'tcx, 'a>(
cx: &'a LateContext<'tcx>,
fn has_significant_drop_in_scrutinee<'tcx>(
cx: &LateContext<'tcx>,
scrutinee: &'tcx Expr<'tcx>,
source: MatchSource,
) -> Option<(Vec<FoundSigDrop>, &'static str)> {
@ -377,7 +377,7 @@ impl<'a, 'tcx> ArmSigDropHelper<'a, 'tcx> {
}
}
fn has_significant_drop_in_arms<'tcx, 'a>(cx: &'a LateContext<'tcx>, arms: &'tcx [Arm<'_>]) -> FxHashSet<Span> {
fn has_significant_drop_in_arms<'tcx>(cx: &LateContext<'tcx>, arms: &'tcx [Arm<'_>]) -> FxHashSet<Span> {
let mut helper = ArmSigDropHelper::new(cx);
for arm in arms {
helper.visit_expr(arm.body);

2
clippy_lints/src/matches/single_match.rs
View File

@ -153,7 +153,7 @@ fn pat_in_candidate_enum<'a>(cx: &LateContext<'a>, ty: Ty<'a>, pat: &Pat<'_>) ->
}
/// Returns `true` if the given type is an enum we know won't be expanded in the future
fn in_candidate_enum<'a>(cx: &LateContext<'a>, ty: Ty<'_>) -> bool {
fn in_candidate_enum(cx: &LateContext<'_>, ty: Ty<'_>) -> bool {
// list of candidate `Enum`s we know will never get any more members
let candidates = [sym::Cow, sym::Option, sym::Result];

4
clippy_lints/src/methods/chars_cmp_with_unwrap.rs
View File

@ -9,8 +9,8 @@ use rustc_lint::LateContext;
use rustc_lint::Lint;
/// Wrapper fn for `CHARS_NEXT_CMP` and `CHARS_LAST_CMP` lints with `unwrap()`.
pub(super) fn check<'tcx>(
cx: &LateContext<'tcx>,
pub(super) fn check(
cx: &LateContext<'_>,
info: &crate::methods::BinaryExprInfo<'_>,
chain_methods: &[&str],
lint: &'static Lint,

2
clippy_lints/src/methods/chars_last_cmp.rs
View File

@ -4,7 +4,7 @@ use rustc_lint::LateContext;
use super::CHARS_LAST_CMP;
/// Checks for the `CHARS_LAST_CMP` lint.
pub(super) fn check<'tcx>(cx: &LateContext<'tcx>, info: &crate::methods::BinaryExprInfo<'_>) -> bool {
pub(super) fn check(cx: &LateContext<'_>, info: &crate::methods::BinaryExprInfo<'_>) -> bool {
if chars_cmp::check(cx, info, &["chars", "last"], CHARS_LAST_CMP, "ends_with") {
true
} else {

2
clippy_lints/src/methods/chars_last_cmp_with_unwrap.rs
View File

@ -4,7 +4,7 @@ use rustc_lint::LateContext;
use super::CHARS_LAST_CMP;
/// Checks for the `CHARS_LAST_CMP` lint with `unwrap()`.
pub(super) fn check<'tcx>(cx: &LateContext<'tcx>, info: &crate::methods::BinaryExprInfo<'_>) -> bool {
pub(super) fn check(cx: &LateContext<'_>, info: &crate::methods::BinaryExprInfo<'_>) -> bool {
if chars_cmp_with_unwrap::check(cx, info, &["chars", "last", "unwrap"], CHARS_LAST_CMP, "ends_with") {
true
} else {

2
clippy_lints/src/methods/chars_next_cmp.rs
View File

@ -3,6 +3,6 @@ use rustc_lint::LateContext;
use super::CHARS_NEXT_CMP;
/// Checks for the `CHARS_NEXT_CMP` lint.
pub(super) fn check<'tcx>(cx: &LateContext<'tcx>, info: &crate::methods::BinaryExprInfo<'_>) -> bool {
pub(super) fn check(cx: &LateContext<'_>, info: &crate::methods::BinaryExprInfo<'_>) -> bool {
crate::methods::chars_cmp::check(cx, info, &["chars", "next"], CHARS_NEXT_CMP, "starts_with")
}

2
clippy_lints/src/methods/chars_next_cmp_with_unwrap.rs
View File

@ -3,6 +3,6 @@ use rustc_lint::LateContext;
use super::CHARS_NEXT_CMP;
/// Checks for the `CHARS_NEXT_CMP` lint with `unwrap()`.
pub(super) fn check<'tcx>(cx: &LateContext<'tcx>, info: &crate::methods::BinaryExprInfo<'_>) -> bool {
pub(super) fn check(cx: &LateContext<'_>, info: &crate::methods::BinaryExprInfo<'_>) -> bool {
crate::methods::chars_cmp_with_unwrap::check(cx, info, &["chars", "next", "unwrap"], CHARS_NEXT_CMP, "starts_with")
}

8
clippy_lints/src/methods/filter_map.rs
View File

@ -17,7 +17,7 @@ use super::MANUAL_FILTER_MAP;
use super::MANUAL_FIND_MAP;
use super::OPTION_FILTER_MAP;
fn is_method<'tcx>(cx: &LateContext<'tcx>, expr: &hir::Expr<'_>, method_name: Symbol) -> bool {
fn is_method(cx: &LateContext<'_>, expr: &hir::Expr<'_>, method_name: Symbol) -> bool {
match &expr.kind {
hir::ExprKind::Path(QPath::TypeRelative(_, mname)) => mname.ident.name == method_name,
hir::ExprKind::Path(QPath::Resolved(_, segments)) => {
@ -46,7 +46,7 @@ fn is_method<'tcx>(cx: &LateContext<'tcx>, expr: &hir::Expr<'_>, method_name: Sy
}
}
fn is_option_filter_map<'tcx>(cx: &LateContext<'tcx>, filter_arg: &hir::Expr<'_>, map_arg: &hir::Expr<'_>) -> bool {
fn is_option_filter_map(cx: &LateContext<'_>, filter_arg: &hir::Expr<'_>, map_arg: &hir::Expr<'_>) -> bool {
is_method(cx, map_arg, sym::unwrap) && is_method(cx, filter_arg, sym!(is_some))
}
@ -66,8 +66,8 @@ fn is_filter_some_map_unwrap(
/// lint use of `filter().map()` or `find().map()` for `Iterators`
#[allow(clippy::too_many_arguments)]
pub(super) fn check<'tcx>(
cx: &LateContext<'tcx>,
pub(super) fn check(
cx: &LateContext<'_>,
expr: &hir::Expr<'_>,
filter_recv: &hir::Expr<'_>,
filter_arg: &hir::Expr<'_>,

4
clippy_lints/src/methods/inefficient_to_string.rs
View File

@ -12,8 +12,8 @@ use rustc_span::symbol::{sym, Symbol};
use super::INEFFICIENT_TO_STRING;
/// Checks for the `INEFFICIENT_TO_STRING` lint
pub fn check<'tcx>(
cx: &LateContext<'tcx>,
pub fn check(
cx: &LateContext<'_>,
expr: &hir::Expr<'_>,
method_name: Symbol,
receiver: &hir::Expr<'_>,

2
clippy_lints/src/methods/iter_nth_zero.rs
View File

@ -10,7 +10,7 @@ use rustc_span::sym;
use super::ITER_NTH_ZERO;
pub(super) fn check<'tcx>(cx: &LateContext<'tcx>, expr: &hir::Expr<'_>, recv: &hir::Expr<'_>, arg: &hir::Expr<'_>) {
pub(super) fn check(cx: &LateContext<'_>, expr: &hir::Expr<'_>, recv: &hir::Expr<'_>, arg: &hir::Expr<'_>) {
if_chain! {
if is_trait_method(cx, expr, sym::Iterator);
if let Some((Constant::Int(0), _)) = constant(cx, cx.typeck_results(), arg);

2
clippy_lints/src/methods/iter_on_single_or_empty_collections.rs
View File

@ -25,7 +25,7 @@ impl IterType {
}
}
pub(super) fn check<'tcx>(cx: &LateContext<'tcx>, expr: &Expr<'_>, method_name: &str, recv: &Expr<'_>) {
pub(super) fn check(cx: &LateContext<'_>, expr: &Expr<'_>, method_name: &str, recv: &Expr<'_>) {
let item = match recv.kind {
ExprKind::Array([]) => None,
ExprKind::Array([e]) => Some(e),

2
clippy_lints/src/methods/manual_saturating_arithmetic.rs
View File

@ -67,7 +67,7 @@ enum MinMax {
Max,
}
fn is_min_or_max<'tcx>(cx: &LateContext<'tcx>, expr: &hir::Expr<'_>) -> Option<MinMax> {
fn is_min_or_max(cx: &LateContext<'_>, expr: &hir::Expr<'_>) -> Option<MinMax> {
// `T::max_value()` `T::min_value()` inherent methods
if_chain! {
if let hir::ExprKind::Call(func, args) = &expr.kind;

4
clippy_lints/src/methods/map_clone.rs
View File

@ -15,11 +15,11 @@ use rustc_span::{sym, Span};
use super::MAP_CLONE;
pub(super) fn check<'tcx>(
pub(super) fn check(
cx: &LateContext<'_>,
e: &hir::Expr<'_>,
recv: &hir::Expr<'_>,
arg: &'tcx hir::Expr<'_>,
arg: &hir::Expr<'_>,
msrv: Option<RustcVersion>,
) {
if_chain! {

2
clippy_lints/src/methods/map_err_ignore.rs
View File

@ -6,7 +6,7 @@ use rustc_span::sym;
use super::MAP_ERR_IGNORE;
pub(super) fn check<'tcx>(cx: &LateContext<'_>, e: &Expr<'_>, arg: &'tcx Expr<'_>) {
pub(super) fn check(cx: &LateContext<'_>, e: &Expr<'_>, arg: &Expr<'_>) {
if let Some(method_id) = cx.typeck_results().type_dependent_def_id(e.hir_id)
&& let Some(impl_id) = cx.tcx.impl_of_method(method_id)
&& is_type_diagnostic_item(cx, cx.tcx.type_of(impl_id), sym::Result)

4
clippy_lints/src/methods/option_as_ref_deref.rs
View File

@ -13,8 +13,8 @@ use rustc_span::sym;
use super::OPTION_AS_REF_DEREF;
/// lint use of `_.as_ref().map(Deref::deref)` for `Option`s
pub(super) fn check<'tcx>(
cx: &LateContext<'tcx>,
pub(super) fn check(
cx: &LateContext<'_>,
expr: &hir::Expr<'_>,
as_ref_recv: &hir::Expr<'_>,
map_arg: &hir::Expr<'_>,

2
clippy_lints/src/methods/suspicious_map.rs
View File

@ -8,7 +8,7 @@ use rustc_span::sym;
use super::SUSPICIOUS_MAP;
pub fn check<'tcx>(cx: &LateContext<'tcx>, expr: &hir::Expr<'_>, count_recv: &hir::Expr<'_>, map_arg: &hir::Expr<'_>) {
pub fn check(cx: &LateContext<'_>, expr: &hir::Expr<'_>, count_recv: &hir::Expr<'_>, map_arg: &hir::Expr<'_>) {
if_chain! {
if is_trait_method(cx, count_recv, sym::Iterator);
let closure = expr_or_init(cx, map_arg);

4
clippy_lints/src/mixed_read_write_in_expression.rs
View File

@ -218,7 +218,7 @@ enum StopEarly {
Stop,
}
fn check_expr<'a, 'tcx>(vis: &mut ReadVisitor<'a, 'tcx>, expr: &'tcx Expr<'_>) -> StopEarly {
fn check_expr<'tcx>(vis: &mut ReadVisitor<'_, 'tcx>, expr: &'tcx Expr<'_>) -> StopEarly {
if expr.hir_id == vis.last_expr.hir_id {
return StopEarly::KeepGoing;
}
@ -265,7 +265,7 @@ fn check_expr<'a, 'tcx>(vis: &mut ReadVisitor<'a, 'tcx>, expr: &'tcx Expr<'_>) -
StopEarly::KeepGoing
}
fn check_stmt<'a, 'tcx>(vis: &mut ReadVisitor<'a, 'tcx>, stmt: &'tcx Stmt<'_>) -> StopEarly {
fn check_stmt<'tcx>(vis: &mut ReadVisitor<'_, 'tcx>, stmt: &'tcx Stmt<'_>) -> StopEarly {
match stmt.kind {
StmtKind::Expr(expr) | StmtKind::Semi(expr) => check_expr(vis, expr),
// If the declaration is of a local variable, check its initializer

2
clippy_lints/src/mut_key.rs
View File

@ -137,7 +137,7 @@ impl MutableKeyType {
}
}
fn check_sig<'tcx>(&self, cx: &LateContext<'tcx>, item_hir_id: hir::HirId, decl: &hir::FnDecl<'_>) {
fn check_sig(&self, cx: &LateContext<'_>, item_hir_id: hir::HirId, decl: &hir::FnDecl<'_>) {
let fn_def_id = cx.tcx.hir().local_def_id(item_hir_id);
let fn_sig = cx.tcx.fn_sig(fn_def_id);
for (hir_ty, ty) in iter::zip(decl.inputs, fn_sig.inputs().skip_binder()) {

8
clippy_lints/src/needless_continue.rs
View File

@ -287,7 +287,7 @@ const DROP_ELSE_BLOCK_MSG: &str = "consider dropping the `else` clause";
const DROP_CONTINUE_EXPRESSION_MSG: &str = "consider dropping the `continue` expression";
fn emit_warning<'a>(cx: &EarlyContext<'_>, data: &'a LintData<'_>, header: &str, typ: LintType) {
fn emit_warning(cx: &EarlyContext<'_>, data: &LintData<'_>, header: &str, typ: LintType) {
// snip is the whole *help* message that appears after the warning.
// message is the warning message.
// expr is the expression which the lint warning message refers to.
@ -313,7 +313,7 @@ fn emit_warning<'a>(cx: &EarlyContext<'_>, data: &'a LintData<'_>, header: &str,
);
}
fn suggestion_snippet_for_continue_inside_if<'a>(cx: &EarlyContext<'_>, data: &'a LintData<'_>) -> String {
fn suggestion_snippet_for_continue_inside_if(cx: &EarlyContext<'_>, data: &LintData<'_>) -> String {
let cond_code = snippet(cx, data.if_cond.span, "..");
let continue_code = snippet_block(cx, data.if_block.span, "..", Some(data.if_expr.span));
@ -327,7 +327,7 @@ fn suggestion_snippet_for_continue_inside_if<'a>(cx: &EarlyContext<'_>, data: &'
)
}
fn suggestion_snippet_for_continue_inside_else<'a>(cx: &EarlyContext<'_>, data: &'a LintData<'_>) -> String {
fn suggestion_snippet_for_continue_inside_else(cx: &EarlyContext<'_>, data: &LintData<'_>) -> String {
let cond_code = snippet(cx, data.if_cond.span, "..");
// Region B
@ -361,7 +361,7 @@ fn suggestion_snippet_for_continue_inside_else<'a>(cx: &EarlyContext<'_>, data:
)
}
fn check_and_warn<'a>(cx: &EarlyContext<'_>, expr: &'a ast::Expr) {
fn check_and_warn(cx: &EarlyContext<'_>, expr: &ast::Expr) {
if_chain! {
if let ast::ExprKind::Loop(loop_block, ..) = &expr.kind;
if let Some(last_stmt) = loop_block.stmts.last();

2
clippy_lints/src/operators/op_ref.rs
View File

@ -199,7 +199,7 @@ fn in_impl<'tcx>(
}
}
fn are_equal<'tcx>(cx: &LateContext<'tcx>, middle_ty: Ty<'_>, hir_ty: &rustc_hir::Ty<'_>) -> bool {
fn are_equal(cx: &LateContext<'_>, middle_ty: Ty<'_>, hir_ty: &rustc_hir::Ty<'_>) -> bool {
if_chain! {
if let ty::Adt(adt_def, _) = middle_ty.kind();
if let Some(local_did) = adt_def.did().as_local();

4
clippy_lints/src/pattern_type_mismatch.rs
View File

@ -130,7 +130,7 @@ enum DerefPossible {
Impossible,
}
fn apply_lint<'tcx>(cx: &LateContext<'tcx>, pat: &Pat<'_>, deref_possible: DerefPossible) -> bool {
fn apply_lint(cx: &LateContext<'_>, pat: &Pat<'_>, deref_possible: DerefPossible) -> bool {
let maybe_mismatch = find_first_mismatch(cx, pat);
if let Some((span, mutability, level)) = maybe_mismatch {
span_lint_and_help(
@ -163,7 +163,7 @@ enum Level {
Lower,
}
fn find_first_mismatch<'tcx>(cx: &LateContext<'tcx>, pat: &Pat<'_>) -> Option<(Span, Mutability, Level)> {
fn find_first_mismatch(cx: &LateContext<'_>, pat: &Pat<'_>) -> Option<(Span, Mutability, Level)> {
let mut result = None;
pat.walk(|p| {
if result.is_some() {

8
clippy_lints/src/ptr_offset_with_cast.rs
View File

@ -105,17 +105,17 @@ fn expr_as_ptr_offset_call<'tcx>(
}
// Is the type of the expression a usize?
fn is_expr_ty_usize<'tcx>(cx: &LateContext<'tcx>, expr: &Expr<'_>) -> bool {
fn is_expr_ty_usize(cx: &LateContext<'_>, 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<'tcx>(cx: &LateContext<'tcx>, expr: &Expr<'_>) -> bool {
fn is_expr_ty_raw_ptr(cx: &LateContext<'_>, expr: &Expr<'_>) -> bool {
cx.typeck_results().expr_ty(expr).is_unsafe_ptr()
}
fn build_suggestion<'tcx>(
cx: &LateContext<'tcx>,
fn build_suggestion(
cx: &LateContext<'_>,
method: Method,
receiver_expr: &Expr<'_>,
cast_lhs_expr: &Expr<'_>,

4
clippy_lints/src/redundant_closure_call.rs
View File

@ -105,8 +105,8 @@ impl EarlyLintPass for RedundantClosureCall {
impl<'tcx> LateLintPass<'tcx> for RedundantClosureCall {
fn check_block(&mut self, cx: &LateContext<'tcx>, block: &'tcx hir::Block<'_>) {
fn count_closure_usage<'a, 'tcx>(
cx: &'a LateContext<'tcx>,
fn count_closure_usage<'tcx>(
cx: &LateContext<'tcx>,
block: &'tcx hir::Block<'_>,
path: &'tcx hir::Path<'tcx>,
) -> usize {

2
clippy_lints/src/slow_vector_initialization.rs
View File

@ -168,7 +168,7 @@ impl SlowVectorInit {
};
}
fn emit_lint<'tcx>(cx: &LateContext<'tcx>, slow_fill: &Expr<'_>, vec_alloc: &VecAllocation<'_>, msg: &str) {
fn emit_lint(cx: &LateContext<'_>, slow_fill: &Expr<'_>, vec_alloc: &VecAllocation<'_>, msg: &str) {
let len_expr = Sugg::hir(cx, vec_alloc.len_expr, "len");
span_lint_and_then(cx, SLOW_VECTOR_INITIALIZATION, slow_fill.span, msg, |diag| {

2
clippy_lints/src/utils/internal_lints/lint_without_lint_pass.rs
View File

@ -256,7 +256,7 @@ impl<'tcx> LateLintPass<'tcx> for LintWithoutLintPass {
}
}
pub(super) fn is_lint_ref_type<'tcx>(cx: &LateContext<'tcx>, ty: &hir::Ty<'_>) -> bool {
pub(super) fn is_lint_ref_type(cx: &LateContext<'_>, ty: &hir::Ty<'_>) -> bool {
if let TyKind::Rptr(
_,
MutTy {

12
clippy_utils/src/diagnostics.rs
View File

@ -72,8 +72,8 @@ pub fn span_lint<T: LintContext>(cx: &T, lint: &'static Lint, sp: impl Into<Mult
/// |
/// = help: consider using `f64::NAN` if you would like a constant representing NaN
/// ```
pub fn span_lint_and_help<'a, T: LintContext>(
cx: &'a T,
pub fn span_lint_and_help<T: LintContext>(
cx: &T,
lint: &'static Lint,
span: impl Into<MultiSpan>,
msg: &str,
@ -114,8 +114,8 @@ pub fn span_lint_and_help<'a, T: LintContext>(
/// 10 | forget(&SomeStruct);
/// | ^^^^^^^^^^^
/// ```
pub fn span_lint_and_note<'a, T: LintContext>(
cx: &'a T,
pub fn span_lint_and_note<T: LintContext>(
cx: &T,
lint: &'static Lint,
span: impl Into<MultiSpan>,
msg: &str,
@ -192,8 +192,8 @@ pub fn span_lint_hir_and_then(
/// = note: `-D fold-any` implied by `-D warnings`
/// ```
#[cfg_attr(feature = "internal", allow(clippy::collapsible_span_lint_calls))]
pub fn span_lint_and_sugg<'a, T: LintContext>(
cx: &'a T,
pub fn span_lint_and_sugg<T: LintContext>(
cx: &T,
lint: &'static Lint,
sp: Span,
msg: &str,

4
clippy_utils/src/lib.rs
View File

@ -994,7 +994,7 @@ impl std::ops::BitOrAssign for CaptureKind {
/// Note as this will walk up to parent expressions until the capture can be determined it should
/// only be used while making a closure somewhere a value is consumed. e.g. a block, match arm, or
/// function argument (other than a receiver).
pub fn capture_local_usage<'tcx>(cx: &LateContext<'tcx>, e: &Expr<'_>) -> CaptureKind {
pub fn capture_local_usage(cx: &LateContext<'_>, e: &Expr<'_>) -> CaptureKind {
fn pat_capture_kind(cx: &LateContext<'_>, pat: &Pat<'_>) -> CaptureKind {
let mut capture = CaptureKind::Ref(Mutability::Not);
pat.each_binding_or_first(&mut |_, id, span, _| match cx
@ -1852,7 +1852,7 @@ pub fn match_any_def_paths(cx: &LateContext<'_>, did: DefId, paths: &[&[&str]])
}
/// Checks if the given `DefId` matches the path.
pub fn match_def_path<'tcx>(cx: &LateContext<'tcx>, did: DefId, syms: &[&str]) -> bool {
pub fn match_def_path(cx: &LateContext<'_>, did: DefId, syms: &[&str]) -> bool {
// We should probably move to Symbols in Clippy as well rather than interning every time.
let path = cx.get_def_path(did);
syms.iter().map(|x| Symbol::intern(x)).eq(path.iter().copied())

6
clippy_utils/src/qualify_min_const_fn.rs
View File

@ -18,7 +18,7 @@ use std::borrow::Cow;
type McfResult = Result<(), (Span, Cow<'static, str>)>;
pub fn is_min_const_fn<'a, 'tcx>(tcx: TyCtxt<'tcx>, body: &'a Body<'tcx>, msrv: Option<RustcVersion>) -> McfResult {
pub fn is_min_const_fn<'tcx>(tcx: TyCtxt<'tcx>, body: &Body<'tcx>, msrv: Option<RustcVersion>) -> McfResult {
let def_id = body.source.def_id();
let mut current = def_id;
loop {
@ -276,9 +276,9 @@ fn check_place<'tcx>(tcx: TyCtxt<'tcx>, place: Place<'tcx>, span: Span, body: &B
Ok(())
}
fn check_terminator<'a, 'tcx>(
fn check_terminator<'tcx>(
tcx: TyCtxt<'tcx>,
body: &'a Body<'tcx>,
body: &Body<'tcx>,
terminator: &Terminator<'tcx>,
msrv: Option<RustcVersion>,
) -> McfResult {

2
clippy_utils/src/sugg.rs
View File

@ -801,7 +801,7 @@ pub struct DerefClosure {
/// Returns `None` if no such use cases have been triggered in closure body
///
/// note: this only works on single line immutable closures with exactly one input parameter.
pub fn deref_closure_args<'tcx>(cx: &LateContext<'_>, closure: &'tcx hir::Expr<'_>) -> Option<DerefClosure> {
pub fn deref_closure_args(cx: &LateContext<'_>, closure: &hir::Expr<'_>) -> Option<DerefClosure> {
if let hir::ExprKind::Closure(&Closure { fn_decl, body, .. }) = closure.kind {
let closure_body = cx.tcx.hir().body(body);
// is closure arg a type annotated double reference (i.e.: `|x: &&i32| ...`)

2
tests/ui/crashes/ice-2774.stderr
View File

@ -1,4 +1,4 @@
error: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
error: the following explicit lifetimes could be elided: 'a
--> $DIR/ice-2774.rs:15:1
|
LL | pub fn add_barfoos_to_foos<'a>(bars: &HashSet<&'a Bar>) {

2
tests/ui/crashes/needless_lifetimes_impl_trait.stderr
View File

@ -1,4 +1,4 @@
error: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
error: the following explicit lifetimes could be elided: 'a
--> $DIR/needless_lifetimes_impl_trait.rs:15:5
|
LL | fn baz<'a>(&'a self) -> impl Foo + 'a {

4
tests/ui/issue_4266.stderr
View File

@ -1,4 +1,4 @@
error: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
error: the following explicit lifetimes could be elided: 'a
--> $DIR/issue_4266.rs:4:1
|
LL | async fn sink1<'a>(_: &'a str) {} // lint
@ -6,7 +6,7 @@ LL | async fn sink1<'a>(_: &'a str) {} // lint
|
= note: `-D clippy::needless-lifetimes` implied by `-D warnings`
error: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
error: the following explicit lifetimes could be elided: 'a
--> $DIR/issue_4266.rs:8:1
|
LL | async fn one_to_one<'a>(s: &'a str) -> &'a str {

2
tests/ui/mut_from_ref.rs
View File

@ -1,4 +1,4 @@
#![allow(unused)]
#![allow(unused, clippy::needless_lifetimes)]
#![warn(clippy::mut_from_ref)]
struct Foo;

96
tests/ui/needless_lifetimes.rs
View File

@ -29,11 +29,20 @@ fn multiple_in_and_out_1<'a>(x: &'a u8, _y: &'a u8) -> &'a u8 {
x
}
// No error; multiple input refs.
fn multiple_in_and_out_2<'a, 'b>(x: &'a u8, _y: &'b u8) -> &'a u8 {
// Error; multiple input refs, but the output lifetime is not elided, i.e., the following is valid:
// fn multiple_in_and_out_2a<'a>(x: &'a u8, _y: &u8) -> &'a u8
// ^^^
fn multiple_in_and_out_2a<'a, 'b>(x: &'a u8, _y: &'b u8) -> &'a u8 {
x
}
// Error; multiple input refs, but the output lifetime is not elided, i.e., the following is valid:
// fn multiple_in_and_out_2b<'b>(_x: &u8, y: &'b u8) -> &'b u8
// ^^^
fn multiple_in_and_out_2b<'a, 'b>(_x: &'a u8, y: &'b u8) -> &'b u8 {
y
}
// No error; multiple input refs
async fn func<'a>(args: &[&'a str]) -> Option<&'a str> {
args.get(0).cloned()
@ -44,11 +53,20 @@ fn in_static_and_out<'a>(x: &'a u8, _y: &'static u8) -> &'a u8 {
x
}
// No error.
fn deep_reference_1<'a, 'b>(x: &'a u8, _y: &'b u8) -> Result<&'a u8, ()> {
// Error; multiple input refs, but the output lifetime is not elided, i.e., the following is valid:
// fn deep_reference_1a<'a>(x: &'a u8, _y: &u8) -> Result<&'a u8, ()>
// ^^^
fn deep_reference_1a<'a, 'b>(x: &'a u8, _y: &'b u8) -> Result<&'a u8, ()> {
Ok(x)
}
// Error; multiple input refs, but the output lifetime is not elided, i.e., the following is valid:
// fn deep_reference_1b<'b>(_x: &u8, y: &'b u8) -> Result<&'b u8, ()>
// ^^^
fn deep_reference_1b<'a, 'b>(_x: &'a u8, y: &'b u8) -> Result<&'b u8, ()> {
Ok(y)
}
// No error; two input refs.
fn deep_reference_2<'a>(x: Result<&'a u8, &'a u8>) -> &'a u8 {
x.unwrap()
@ -129,11 +147,20 @@ impl X {
&self.x
}
// No error; multiple input refs.
fn self_and_in_out<'s, 't>(&'s self, _x: &'t u8) -> &'s u8 {
// Error; multiple input refs, but the output lifetime is not elided, i.e., the following is valid:
// fn self_and_in_out_1<'s>(&'s self, _x: &u8) -> &'s u8
// ^^^
fn self_and_in_out_1<'s, 't>(&'s self, _x: &'t u8) -> &'s u8 {
&self.x
}
// Error; multiple input refs, but the output lifetime is not elided, i.e., the following is valid:
// fn self_and_in_out_2<'t>(&self, x: &'t u8) -> &'t u8
// ^^^^^
fn self_and_in_out_2<'s, 't>(&'s self, x: &'t u8) -> &'t u8 {
x
}
fn distinct_self_and_in<'s, 't>(&'s self, _x: &'t u8) {}
// No error; same lifetimes on two params.
@ -167,8 +194,19 @@ fn struct_with_lt3<'a>(_foo: &Foo<'a>) -> &'a str {
unimplemented!()
}
// No warning; two input lifetimes.
fn struct_with_lt4<'a, 'b>(_foo: &'a Foo<'b>) -> &'a str {
// Warning; two input lifetimes, but the output lifetime is not elided, i.e., the following is
// valid:
// fn struct_with_lt4a<'a>(_foo: &'a Foo<'_>) -> &'a str
// ^^
fn struct_with_lt4a<'a, 'b>(_foo: &'a Foo<'b>) -> &'a str {
unimplemented!()
}
// Warning; two input lifetimes, but the output lifetime is not elided, i.e., the following is
// valid:
// fn struct_with_lt4b<'b>(_foo: &Foo<'b>) -> &'b str
// ^^^^
fn struct_with_lt4b<'a, 'b>(_foo: &'a Foo<'b>) -> &'b str {
unimplemented!()
}
@ -203,8 +241,19 @@ fn alias_with_lt3<'a>(_foo: &FooAlias<'a>) -> &'a str {
unimplemented!()
}
// No warning; two input lifetimes.
fn alias_with_lt4<'a, 'b>(_foo: &'a FooAlias<'b>) -> &'a str {
// Warning; two input lifetimes, but the output lifetime is not elided, i.e., the following is
// valid:
// fn alias_with_lt4a<'a>(_foo: &'a FooAlias<'_>) -> &'a str
// ^^
fn alias_with_lt4a<'a, 'b>(_foo: &'a FooAlias<'b>) -> &'a str {
unimplemented!()
}
// Warning; two input lifetimes, but the output lifetime is not elided, i.e., the following is
// valid:
// fn alias_with_lt4b<'b>(_foo: &FooAlias<'b>) -> &'b str
// ^^^^^^^^^
fn alias_with_lt4b<'a, 'b>(_foo: &'a FooAlias<'b>) -> &'b str {
unimplemented!()
}
@ -419,4 +468,31 @@ mod issue7296 {
}
}
mod pr_9743_false_negative_fix {
#![allow(unused)]
fn foo<'a>(x: &'a u8, y: &'_ u8) {}
fn bar<'a>(x: &'a u8, y: &'_ u8, z: &'_ u8) {}
}
mod pr_9743_output_lifetime_checks {
#![allow(unused)]
// lint: only one input
fn one_input<'a>(x: &'a u8) -> &'a u8 {
unimplemented!()
}
// lint: multiple inputs, output would not be elided
fn multiple_inputs_output_not_elided<'a, 'b>(x: &'a u8, y: &'b u8, z: &'b u8) -> &'b u8 {
unimplemented!()
}
// don't lint: multiple inputs, output would be elided (which would create an ambiguity)
fn multiple_inputs_output_would_be_elided<'a, 'b>(x: &'a u8, y: &'b u8, z: &'b u8) -> &'a u8 {
unimplemented!()
}
}
fn main() {}

246
tests/ui/needless_lifetimes.stderr
View File

@ -1,4 +1,4 @@
error: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
error: the following explicit lifetimes could be elided: 'a, 'b
--> $DIR/needless_lifetimes.rs:11:1
|
LL | fn distinct_lifetimes<'a, 'b>(_x: &'a u8, _y: &'b u8, _z: u8) {}
@ -6,185 +6,311 @@ LL | fn distinct_lifetimes<'a, 'b>(_x: &'a u8, _y: &'b u8, _z: u8) {}
|
= note: `-D clippy::needless-lifetimes` implied by `-D warnings`
error: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
error: the following explicit lifetimes could be elided: 'a, 'b
--> $DIR/needless_lifetimes.rs:13:1
|
LL | fn distinct_and_static<'a, 'b>(_x: &'a u8, _y: &'b u8, _z: &'static u8) {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
error: the following explicit lifetimes could be elided: 'a
--> $DIR/needless_lifetimes.rs:23:1
|
LL | fn in_and_out<'a>(x: &'a u8, _y: u8) -> &'a u8 {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
--> $DIR/needless_lifetimes.rs:57:1
error: the following explicit lifetimes could be elided: 'b
--> $DIR/needless_lifetimes.rs:35:1
|
LL | fn multiple_in_and_out_2a<'a, 'b>(x: &'a u8, _y: &'b u8) -> &'a u8 {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: the following explicit lifetimes could be elided: 'a
--> $DIR/needless_lifetimes.rs:42:1
|
LL | fn multiple_in_and_out_2b<'a, 'b>(_x: &'a u8, y: &'b u8) -> &'b u8 {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: the following explicit lifetimes could be elided: 'b
--> $DIR/needless_lifetimes.rs:59:1
|
LL | fn deep_reference_1a<'a, 'b>(x: &'a u8, _y: &'b u8) -> Result<&'a u8, ()> {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: the following explicit lifetimes could be elided: 'a
--> $DIR/needless_lifetimes.rs:66:1
|
LL | fn deep_reference_1b<'a, 'b>(_x: &'a u8, y: &'b u8) -> Result<&'b u8, ()> {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: the following explicit lifetimes could be elided: 'a
--> $DIR/needless_lifetimes.rs:75:1
|
LL | fn deep_reference_3<'a>(x: &'a u8, _y: u8) -> Result<&'a u8, ()> {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
--> $DIR/needless_lifetimes.rs:62:1
error: the following explicit lifetimes could be elided: 'a
--> $DIR/needless_lifetimes.rs:80:1
|
LL | fn where_clause_without_lt<'a, T>(x: &'a u8, _y: u8) -> Result<&'a u8, ()>
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
--> $DIR/needless_lifetimes.rs:74:1
error: the following explicit lifetimes could be elided: 'a, 'b
--> $DIR/needless_lifetimes.rs:92:1
|
LL | fn lifetime_param_2<'a, 'b>(_x: Ref<'a>, _y: &'b u8) {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
help: replace with `'_` in generic arguments such as here
--> $DIR/needless_lifetimes.rs:92:37
|
LL | fn lifetime_param_2<'a, 'b>(_x: Ref<'a>, _y: &'b u8) {}
| ^^
error: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
--> $DIR/needless_lifetimes.rs:98:1
error: the following explicit lifetimes could be elided: 'a
--> $DIR/needless_lifetimes.rs:116:1
|
LL | fn fn_bound_2<'a, F, I>(_m: Lt<'a, I>, _f: F) -> Lt<'a, I>
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
help: replace with `'_` in generic arguments such as here
--> $DIR/needless_lifetimes.rs:116:32
|
LL | fn fn_bound_2<'a, F, I>(_m: Lt<'a, I>, _f: F) -> Lt<'a, I>
| ^^
error: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
--> $DIR/needless_lifetimes.rs:128:5
error: the following explicit lifetimes could be elided: 's
--> $DIR/needless_lifetimes.rs:146:5
|
LL | fn self_and_out<'s>(&'s self) -> &'s u8 {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
--> $DIR/needless_lifetimes.rs:137:5
error: the following explicit lifetimes could be elided: 't
--> $DIR/needless_lifetimes.rs:153:5
|
LL | fn self_and_in_out_1<'s, 't>(&'s self, _x: &'t u8) -> &'s u8 {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: the following explicit lifetimes could be elided: 's
--> $DIR/needless_lifetimes.rs:160:5
|
LL | fn self_and_in_out_2<'s, 't>(&'s self, x: &'t u8) -> &'t u8 {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: the following explicit lifetimes could be elided: 's, 't
--> $DIR/needless_lifetimes.rs:164:5
|
LL | fn distinct_self_and_in<'s, 't>(&'s self, _x: &'t u8) {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
--> $DIR/needless_lifetimes.rs:156:1
error: the following explicit lifetimes could be elided: 'a
--> $DIR/needless_lifetimes.rs:183:1
|
LL | fn struct_with_lt<'a>(_foo: Foo<'a>) -> &'a str {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
help: replace with `'_` in generic arguments such as here
--> $DIR/needless_lifetimes.rs:183:33
|
LL | fn struct_with_lt<'a>(_foo: Foo<'a>) -> &'a str {
| ^^
error: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
--> $DIR/needless_lifetimes.rs:186:1
error: the following explicit lifetimes could be elided: 'b
--> $DIR/needless_lifetimes.rs:201:1
|
LL | fn struct_with_lt4a<'a, 'b>(_foo: &'a Foo<'b>) -> &'a str {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
help: replace with `'_` in generic arguments such as here
--> $DIR/needless_lifetimes.rs:201:43
|
LL | fn struct_with_lt4a<'a, 'b>(_foo: &'a Foo<'b>) -> &'a str {
| ^^
error: the following explicit lifetimes could be elided: 'a
--> $DIR/needless_lifetimes.rs:209:1
|
LL | fn struct_with_lt4b<'a, 'b>(_foo: &'a Foo<'b>) -> &'b str {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: the following explicit lifetimes could be elided: 'a
--> $DIR/needless_lifetimes.rs:224:1
|
LL | fn trait_obj_elided2<'a>(_arg: &'a dyn Drop) -> &'a str {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
--> $DIR/needless_lifetimes.rs:192:1
error: the following explicit lifetimes could be elided: 'a
--> $DIR/needless_lifetimes.rs:230:1
|
LL | fn alias_with_lt<'a>(_foo: FooAlias<'a>) -> &'a str {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
help: replace with `'_` in generic arguments such as here
--> $DIR/needless_lifetimes.rs:230:37
|
LL | fn alias_with_lt<'a>(_foo: FooAlias<'a>) -> &'a str {
| ^^
error: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
--> $DIR/needless_lifetimes.rs:211:1
error: the following explicit lifetimes could be elided: 'b
--> $DIR/needless_lifetimes.rs:248:1
|
LL | fn alias_with_lt4a<'a, 'b>(_foo: &'a FooAlias<'b>) -> &'a str {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
help: replace with `'_` in generic arguments such as here
--> $DIR/needless_lifetimes.rs:248:47
|
LL | fn alias_with_lt4a<'a, 'b>(_foo: &'a FooAlias<'b>) -> &'a str {
| ^^
error: the following explicit lifetimes could be elided: 'a
--> $DIR/needless_lifetimes.rs:256:1
|
LL | fn alias_with_lt4b<'a, 'b>(_foo: &'a FooAlias<'b>) -> &'b str {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: the following explicit lifetimes could be elided: 'a
--> $DIR/needless_lifetimes.rs:260:1
|
LL | fn named_input_elided_output<'a>(_arg: &'a str) -> &str {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
--> $DIR/needless_lifetimes.rs:219:1
error: the following explicit lifetimes could be elided: 'a
--> $DIR/needless_lifetimes.rs:268:1
|
LL | fn trait_bound_ok<'a, T: WithLifetime<'static>>(_: &'a u8, _: T) {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
--> $DIR/needless_lifetimes.rs:255:1
error: the following explicit lifetimes could be elided: 'a
--> $DIR/needless_lifetimes.rs:304:1
|
LL | fn out_return_type_lts<'a>(e: &'a str) -> Cow<'a> {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
help: replace with `'_` in generic arguments such as here
--> $DIR/needless_lifetimes.rs:304:47
|
LL | fn out_return_type_lts<'a>(e: &'a str) -> Cow<'a> {
| ^^
error: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
--> $DIR/needless_lifetimes.rs:262:9
error: the following explicit lifetimes could be elided: 'a
--> $DIR/needless_lifetimes.rs:311:9
|
LL | fn needless_lt<'a>(x: &'a u8) {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
--> $DIR/needless_lifetimes.rs:266:9
error: the following explicit lifetimes could be elided: 'a
--> $DIR/needless_lifetimes.rs:315:9
|
LL | fn needless_lt<'a>(_x: &'a u8) {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
--> $DIR/needless_lifetimes.rs:279:9
error: the following explicit lifetimes could be elided: 'a
--> $DIR/needless_lifetimes.rs:328:9
|
LL | fn baz<'a>(&'a self) -> impl Foo + 'a {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
--> $DIR/needless_lifetimes.rs:311:5
error: the following explicit lifetimes could be elided: 'a
--> $DIR/needless_lifetimes.rs:360:5
|
LL | fn impl_trait_elidable_nested_anonymous_lifetimes<'a>(i: &'a i32, f: impl Fn(&i32) -> &i32) -> &'a i32 {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
--> $DIR/needless_lifetimes.rs:320:5
error: the following explicit lifetimes could be elided: 'a
--> $DIR/needless_lifetimes.rs:369:5
|
LL | fn generics_elidable<'a, T: Fn(&i32) -> &i32>(i: &'a i32, f: T) -> &'a i32 {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
--> $DIR/needless_lifetimes.rs:332:5
error: the following explicit lifetimes could be elided: 'a
--> $DIR/needless_lifetimes.rs:381:5
|
LL | fn where_clause_elidadable<'a, T>(i: &'a i32, f: T) -> &'a i32
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
--> $DIR/needless_lifetimes.rs:347:5
error: the following explicit lifetimes could be elided: 'a
--> $DIR/needless_lifetimes.rs:396:5
|
LL | fn pointer_fn_elidable<'a>(i: &'a i32, f: fn(&i32) -> &i32) -> &'a i32 {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
--> $DIR/needless_lifetimes.rs:360:5
error: the following explicit lifetimes could be elided: 'a
--> $DIR/needless_lifetimes.rs:409:5
|
LL | fn nested_fn_pointer_3<'a>(_: &'a i32) -> fn(fn(&i32) -> &i32) -> i32 {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
--> $DIR/needless_lifetimes.rs:363:5
error: the following explicit lifetimes could be elided: 'a
--> $DIR/needless_lifetimes.rs:412:5
|
LL | fn nested_fn_pointer_4<'a>(_: &'a i32) -> impl Fn(fn(&i32)) {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
--> $DIR/needless_lifetimes.rs:385:9
error: the following explicit lifetimes could be elided: 'a
--> $DIR/needless_lifetimes.rs:434:9
|
LL | fn implicit<'a>(&'a self) -> &'a () {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
--> $DIR/needless_lifetimes.rs:388:9
error: the following explicit lifetimes could be elided: 'a
--> $DIR/needless_lifetimes.rs:437:9
|
LL | fn implicit_mut<'a>(&'a mut self) -> &'a () {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
--> $DIR/needless_lifetimes.rs:399:9
error: the following explicit lifetimes could be elided: 'a
--> $DIR/needless_lifetimes.rs:448:9
|
LL | fn lifetime_elsewhere<'a>(self: Box<Self>, here: &'a ()) -> &'a () {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
--> $DIR/needless_lifetimes.rs:405:9
error: the following explicit lifetimes could be elided: 'a
--> $DIR/needless_lifetimes.rs:454:9
|
LL | fn implicit<'a>(&'a self) -> &'a ();
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
--> $DIR/needless_lifetimes.rs:406:9
error: the following explicit lifetimes could be elided: 'a
--> $DIR/needless_lifetimes.rs:455:9
|
LL | fn implicit_provided<'a>(&'a self) -> &'a () {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
--> $DIR/needless_lifetimes.rs:415:9
error: the following explicit lifetimes could be elided: 'a
--> $DIR/needless_lifetimes.rs:464:9
|
LL | fn lifetime_elsewhere<'a>(self: Box<Self>, here: &'a ()) -> &'a ();
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: explicit lifetimes given in parameter types where they could be elided (or replaced with `'_` if needed by type declaration)
--> $DIR/needless_lifetimes.rs:416:9
error: the following explicit lifetimes could be elided: 'a
--> $DIR/needless_lifetimes.rs:465:9
|
LL | fn lifetime_elsewhere_provided<'a>(self: Box<Self>, here: &'a ()) -> &'a () {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: aborting due to 31 previous errors
error: the following explicit lifetimes could be elided: 'a
--> $DIR/needless_lifetimes.rs:474:5
|
LL | fn foo<'a>(x: &'a u8, y: &'_ u8) {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: the following explicit lifetimes could be elided: 'a
--> $DIR/needless_lifetimes.rs:476:5
|
LL | fn bar<'a>(x: &'a u8, y: &'_ u8, z: &'_ u8) {}
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: the following explicit lifetimes could be elided: 'a
--> $DIR/needless_lifetimes.rs:483:5
|
LL | fn one_input<'a>(x: &'a u8) -> &'a u8 {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: the following explicit lifetimes could be elided: 'a
--> $DIR/needless_lifetimes.rs:488:5
|
LL | fn multiple_inputs_output_not_elided<'a, 'b>(x: &'a u8, y: &'b u8, z: &'b u8) -> &'b u8 {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: aborting due to 45 previous errors

2
tests/ui/transmute.rs
View File

@ -1,4 +1,4 @@
#![allow(dead_code, clippy::borrow_as_ptr)]
#![allow(dead_code, clippy::borrow_as_ptr, clippy::needless_lifetimes)]
extern crate core;

1
tests/ui/trivially_copy_pass_by_ref.rs
View File

@ -3,6 +3,7 @@
#![deny(clippy::trivially_copy_pass_by_ref)]
#![allow(
clippy::disallowed_names,
clippy::needless_lifetimes,
clippy::redundant_field_names,
clippy::uninlined_format_args
)]

36
tests/ui/trivially_copy_pass_by_ref.stderr
View File

@ -1,5 +1,5 @@
error: this argument (N byte) is passed by reference, but would be more efficient if passed by value (limit: N byte)
--> $DIR/trivially_copy_pass_by_ref.rs:50:11
--> $DIR/trivially_copy_pass_by_ref.rs:51:11
|
LL | fn bad(x: &u32, y: &Foo, z: &Baz) {}
| ^^^^ help: consider passing by value instead: `u32`
@ -11,103 +11,103 @@ LL | #![deny(clippy::trivially_copy_pass_by_ref)]
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
error: this argument (N byte) is passed by reference, but would be more efficient if passed by value (limit: N byte)
--> $DIR/trivially_copy_pass_by_ref.rs:50:20
--> $DIR/trivially_copy_pass_by_ref.rs:51:20
|
LL | fn bad(x: &u32, y: &Foo, z: &Baz) {}
| ^^^^ help: consider passing by value instead: `Foo`
error: this argument (N byte) is passed by reference, but would be more efficient if passed by value (limit: N byte)
--> $DIR/trivially_copy_pass_by_ref.rs:50:29
--> $DIR/trivially_copy_pass_by_ref.rs:51:29
|
LL | fn bad(x: &u32, y: &Foo, z: &Baz) {}
| ^^^^ help: consider passing by value instead: `Baz`
error: this argument (N byte) is passed by reference, but would be more efficient if passed by value (limit: N byte)
--> $DIR/trivially_copy_pass_by_ref.rs:57:12
--> $DIR/trivially_copy_pass_by_ref.rs:58:12
|
LL | fn bad(&self, x: &u32, y: &Foo, z: &Baz) {}
| ^^^^^ help: consider passing by value instead: `self`
error: this argument (N byte) is passed by reference, but would be more efficient if passed by value (limit: N byte)
--> $DIR/trivially_copy_pass_by_ref.rs:57:22
--> $DIR/trivially_copy_pass_by_ref.rs:58:22
|
LL | fn bad(&self, x: &u32, y: &Foo, z: &Baz) {}
| ^^^^ help: consider passing by value instead: `u32`
error: this argument (N byte) is passed by reference, but would be more efficient if passed by value (limit: N byte)
--> $DIR/trivially_copy_pass_by_ref.rs:57:31
--> $DIR/trivially_copy_pass_by_ref.rs:58:31
|
LL | fn bad(&self, x: &u32, y: &Foo, z: &Baz) {}
| ^^^^ help: consider passing by value instead: `Foo`
error: this argument (N byte) is passed by reference, but would be more efficient if passed by value (limit: N byte)
--> $DIR/trivially_copy_pass_by_ref.rs:57:40
--> $DIR/trivially_copy_pass_by_ref.rs:58:40
|
LL | fn bad(&self, x: &u32, y: &Foo, z: &Baz) {}
| ^^^^ help: consider passing by value instead: `Baz`
error: this argument (N byte) is passed by reference, but would be more efficient if passed by value (limit: N byte)
--> $DIR/trivially_copy_pass_by_ref.rs:59:16
--> $DIR/trivially_copy_pass_by_ref.rs:60:16
|
LL | fn bad2(x: &u32, y: &Foo, z: &Baz) {}
| ^^^^ help: consider passing by value instead: `u32`
error: this argument (N byte) is passed by reference, but would be more efficient if passed by value (limit: N byte)
--> $DIR/trivially_copy_pass_by_ref.rs:59:25
--> $DIR/trivially_copy_pass_by_ref.rs:60:25
|
LL | fn bad2(x: &u32, y: &Foo, z: &Baz) {}
| ^^^^ help: consider passing by value instead: `Foo`
error: this argument (N byte) is passed by reference, but would be more efficient if passed by value (limit: N byte)
--> $DIR/trivially_copy_pass_by_ref.rs:59:34
--> $DIR/trivially_copy_pass_by_ref.rs:60:34
|
LL | fn bad2(x: &u32, y: &Foo, z: &Baz) {}
| ^^^^ help: consider passing by value instead: `Baz`
error: this argument (N byte) is passed by reference, but would be more efficient if passed by value (limit: N byte)
--> $DIR/trivially_copy_pass_by_ref.rs:61:35
--> $DIR/trivially_copy_pass_by_ref.rs:62:35
|
LL | fn bad_issue7518(self, other: &Self) {}
| ^^^^^ help: consider passing by value instead: `Self`
error: this argument (N byte) is passed by reference, but would be more efficient if passed by value (limit: N byte)
--> $DIR/trivially_copy_pass_by_ref.rs:73:16
--> $DIR/trivially_copy_pass_by_ref.rs:74:16
|
LL | fn bad2(x: &u32, y: &Foo, z: &Baz) {}
| ^^^^ help: consider passing by value instead: `u32`
error: this argument (N byte) is passed by reference, but would be more efficient if passed by value (limit: N byte)
--> $DIR/trivially_copy_pass_by_ref.rs:73:25
--> $DIR/trivially_copy_pass_by_ref.rs:74:25
|
LL | fn bad2(x: &u32, y: &Foo, z: &Baz) {}
| ^^^^ help: consider passing by value instead: `Foo`
error: this argument (N byte) is passed by reference, but would be more efficient if passed by value (limit: N byte)
--> $DIR/trivially_copy_pass_by_ref.rs:73:34
--> $DIR/trivially_copy_pass_by_ref.rs:74:34
|
LL | fn bad2(x: &u32, y: &Foo, z: &Baz) {}
| ^^^^ help: consider passing by value instead: `Baz`
error: this argument (N byte) is passed by reference, but would be more efficient if passed by value (limit: N byte)
--> $DIR/trivially_copy_pass_by_ref.rs:77:34
--> $DIR/trivially_copy_pass_by_ref.rs:78:34
|
LL | fn trait_method(&self, _foo: &Foo);
| ^^^^ help: consider passing by value instead: `Foo`
error: this argument (N byte) is passed by reference, but would be more efficient if passed by value (limit: N byte)
--> $DIR/trivially_copy_pass_by_ref.rs:109:21
--> $DIR/trivially_copy_pass_by_ref.rs:110:21
|
LL | fn foo_never(x: &i32) {
| ^^^^ help: consider passing by value instead: `i32`
error: this argument (N byte) is passed by reference, but would be more efficient if passed by value (limit: N byte)
--> $DIR/trivially_copy_pass_by_ref.rs:114:15
--> $DIR/trivially_copy_pass_by_ref.rs:115:15
|
LL | fn foo(x: &i32) {
| ^^^^ help: consider passing by value instead: `i32`
error: this argument (N byte) is passed by reference, but would be more efficient if passed by value (limit: N byte)
--> $DIR/trivially_copy_pass_by_ref.rs:141:37
--> $DIR/trivially_copy_pass_by_ref.rs:142:37
|
LL | fn _unrelated_lifetimes<'a, 'b>(_x: &'a u32, y: &'b u32) -> &'b u32 {
| ^^^^^^^ help: consider passing by value instead: `u32`