noop_method_call: fix and improve derive suggestions
#134903
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| LL - v.clone(); | ||
| LL + v; | ||
| | | ||
| help: if you meant to clone `non_clone_types::DifferentlyConditionalClone<PlainType<u8>>`, implement `Clone` for it |
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I'm not sure why this derive below is being suggested, since the bound is T: Default instead of T: Clone here.
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It looks like the problem is that cx.tcx.predicates_of(trait_impl_id) is actually empty in this case.
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Same with this, you can modify
.derive_suggestion = if you meant to clone `{$orig_ty}`, implement `Clone` for it
to be
.derive_suggestion = if you meant to clone `{$non_clone_ty}`, implement `Clone` for it
| LL - v.clone(); | ||
| LL + v; | ||
| | | ||
| help: if you meant to clone `non_clone_types::DifferentlyConditionalClone<PlainType<u8>>`, implement `Clone` for it |
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Same with this, you can modify
.derive_suggestion = if you meant to clone `{$orig_ty}`, implement `Clone` for it
to be
.derive_suggestion = if you meant to clone `{$non_clone_ty}`, implement `Clone` for it
… to derive on generic argument
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| ty::Adt(def, args) => { | ||
| if def.did().is_local() { | ||
| Some(cx.tcx.def_span(def.did()).shrink_to_lo()) | ||
| } else if let Some(trait_impl_id) = cx.tcx.impl_of_method(i.def_id()) { |
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i.def_id() is the wrong DefId, because it points to the Clone implementation for &T in core. How can I resolve the definition of T::clone (where T is orig_ty) instead?
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I think you can use let args = tcx.mk_args(&[ty::GenericArg::from(orig_ty)]); for a new ty::Instance::try_resolve(cx.tcx, cx.typing_env(), did, args) call.
| @@ -63,14 +63,14 @@ help: remove this redundant call | |||
| LL - let non_borrow_type_borrow: &PlainType<u32> = non_borrow_type.borrow(); | |||
| LL + let non_borrow_type_borrow: &PlainType<u32> = non_borrow_type; | |||
| | | |||
| help: if you meant to clone `PlainType<u32>`, implement `Clone` for it | |||
| help: if you meant to clone `PlainType<u32>`, implement `Clone` for `PlainType<u32>` | |||
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It would be ideal if we didn't repeat the type when orig_ty == non_clone_ty.
Fixes #134471.
If
&Tis being cloned andTis not crate-local, stop suggesting#[derive(Clone)]forTin the message.If
&T<U>is being cloned andTis not crate-local, but implementsCloneifU: Clone, then try suggesting#[derive(Clone)]forUif it is local.r? estebank