mikros/rust
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Lint trait duplication in one pass.

Browse Source
This commit is contained in:
Allen Hsu 2022-08-12 12:51:58 +10:00
parent 3ddc04f4db
commit 8bae517c2d
2 changed files with 23 additions and 40 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

55
clippy_lints/src/trait_bounds.rs
View File

@ -103,7 +103,6 @@ impl<'tcx> LateLintPass<'tcx> for TraitBounds {
fn check_generics(&mut self, cx: &LateContext<'tcx>, gen: &'tcx Generics<'_>) {
self.check_type_repetition(cx, gen);
check_trait_bound_duplication(cx, gen);
check_bounds_or_where_duplication(cx, gen);
}
fn check_item(&mut self, cx: &LateContext<'tcx>, item: &'tcx Item<'tcx>) {
@ -234,7 +233,7 @@ impl TraitBounds {
}
fn check_trait_bound_duplication(cx: &LateContext<'_>, gen: &'_ Generics<'_>) {
if gen.span.from_expansion() || gen.params.is_empty() || gen.predicates.is_empty() {
if gen.span.from_expansion() {
return;
}
@ -254,9 +253,9 @@ fn check_trait_bound_duplication(cx: &LateContext<'_>, gen: &'_ Generics<'_>) {
if let WherePredicate::BoundPredicate(bound_predicate) = pred;
if let TyKind::Path(QPath::Resolved(_, path)) = bound_predicate.bounded_ty.kind;
then {
return Some(bound_predicate.bounds.iter().filter_map(|t| {
Some((path.res, into_comparable_trait_ref(t.trait_ref()?)))
}))
return Some(
rollup_traits(cx, bound_predicate.bounds, "these where clauses contain repeated elements")
.into_keys().map(|trait_ref| (path.res, trait_ref)))
}
}
None
@ -277,19 +276,18 @@ fn check_trait_bound_duplication(cx: &LateContext<'_>, gen: &'_ Generics<'_>) {
if !bound_predicate.span.from_expansion();
if let TyKind::Path(QPath::Resolved(_, path)) = bound_predicate.bounded_ty.kind;
then {
for t in bound_predicate.bounds {
if let Some(trait_ref) = t.trait_ref() {
let key = (path.res, into_comparable_trait_ref(trait_ref));
if where_predicates.contains(&key) {
span_lint_and_help(
cx,
TRAIT_DUPLICATION_IN_BOUNDS,
t.span(),
"this trait bound is already specified in the where clause",
None,
"consider removing this trait bound",
);
}
let traits = rollup_traits(cx, bound_predicate.bounds, "these bounds contain repeated elements");
for (trait_ref, span) in traits {
let key = (path.res, trait_ref);
if where_predicates.contains(&key) {
span_lint_and_help(
cx,
TRAIT_DUPLICATION_IN_BOUNDS,
span,
"this trait bound is already specified in the where clause",
None,
"consider removing this trait bound",
);
}
}
}
@ -300,23 +298,6 @@ fn check_trait_bound_duplication(cx: &LateContext<'_>, gen: &'_ Generics<'_>) {
#[derive(PartialEq, Eq, Hash, Debug)]
struct ComparableTraitRef(Res, Vec<Res>);
fn check_bounds_or_where_duplication(cx: &LateContext<'_>, gen: &'_ Generics<'_>) {
if gen.span.from_expansion() {
return;
}
for predicate in gen.predicates {
if let WherePredicate::BoundPredicate(ref bound_predicate) = predicate {
let msg = if predicate.in_where_clause() {
"these where clauses contain repeated elements"
} else {
"these bounds contain repeated elements"
};
rollup_traits(cx, bound_predicate.bounds, msg);
}
}
}
fn get_trait_info_from_bound<'a>(bound: &'a GenericBound<'_>) -> Option<(Res, &'a [PathSegment<'a>], Span)> {
if let GenericBound::Trait(t, tbm) = bound {
let trait_path = t.trait_ref.path;
@ -358,7 +339,7 @@ fn into_comparable_trait_ref(trait_ref: &TraitRef<'_>) -> ComparableTraitRef {
)
}
fn rollup_traits(cx: &LateContext<'_>, bounds: &[GenericBound<'_>], msg: &str) {
fn rollup_traits(cx: &LateContext<'_>, bounds: &[GenericBound<'_>], msg: &str) -> FxHashMap<ComparableTraitRef, Span> {
let mut map = FxHashMap::default();
let mut repeated_res = false;
@ -400,4 +381,6 @@ fn rollup_traits(cx: &LateContext<'_>, bounds: &[GenericBound<'_>], msg: &str) {
);
}
}
map
}

8
tests/ui/trait_duplication_in_bounds_unfixable.stderr
View File

@ -1,8 +1,8 @@
error: this trait bound is already specified in the where clause
--> $DIR/trait_duplication_in_bounds_unfixable.rs:6:15
--> $DIR/trait_duplication_in_bounds_unfixable.rs:6:23
|
LL | fn bad_foo<T: Clone + Default, Z: Copy>(arg0: T, arg1: Z)
| ^^^^^
| ^^^^^^^
|
note: the lint level is defined here
--> $DIR/trait_duplication_in_bounds_unfixable.rs:1:9
@ -12,10 +12,10 @@ LL | #![deny(clippy::trait_duplication_in_bounds)]
= help: consider removing this trait bound
error: this trait bound is already specified in the where clause
--> $DIR/trait_duplication_in_bounds_unfixable.rs:6:23
--> $DIR/trait_duplication_in_bounds_unfixable.rs:6:15
|
LL | fn bad_foo<T: Clone + Default, Z: Copy>(arg0: T, arg1: Z)
| ^^^^^^^
| ^^^^^
|
= help: consider removing this trait bound