39 lines
1.2 KiB
Rust
39 lines
1.2 KiB
Rust
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use clippy_utils::diagnostics::span_lint_and_sugg;
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use clippy_utils::is_trait_method;
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use clippy_utils::ty::{get_iterator_item_ty, is_copy};
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use rustc_errors::Applicability;
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use rustc_hir::Expr;
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use rustc_lint::LateContext;
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use rustc_middle::ty;
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use rustc_span::{sym, Span};
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use super::CLONED_INSTEAD_OF_COPIED;
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pub fn check(cx: &LateContext<'_>, expr: &Expr<'_>, recv: &Expr<'_>, span: Span) {
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let recv_ty = cx.typeck_results().expr_ty_adjusted(recv);
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let inner_ty = match recv_ty.kind() {
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// `Option<T>` -> `T`
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ty::Adt(adt, subst) if cx.tcx.is_diagnostic_item(sym::option_type, adt.did) => subst.type_at(0),
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_ if is_trait_method(cx, expr, sym::Iterator) => match get_iterator_item_ty(cx, recv_ty) {
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// <T as Iterator>::Item
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Some(ty) => ty,
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_ => return,
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},
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_ => return,
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};
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match inner_ty.kind() {
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// &T where T: Copy
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ty::Ref(_, ty, _) if is_copy(cx, ty) => {},
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_ => return,
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};
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span_lint_and_sugg(
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cx,
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CLONED_INSTEAD_OF_COPIED,
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span,
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"used `cloned` where `copied` could be used instead",
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"try",
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"copied".into(),
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Applicability::MachineApplicable,
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)
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}
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