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077fc26f0a
Uplift `clippy::{drop,forget}_{ref,copy}` lints
This PR aims at uplifting the `clippy::drop_ref`, `clippy::drop_copy`, `clippy::forget_ref` and `clippy::forget_copy` lints.
Those lints are/were declared in the correctness category of clippy because they lint on useless and most probably is not what the developer wanted.
## `drop_ref` and `forget_ref`
The `drop_ref` and `forget_ref` lint checks for calls to `std::mem::drop` or `std::mem::forget` with a reference instead of an owned value.
### Example
```rust
let mut lock_guard = mutex.lock();
std::mem::drop(&lock_guard) // Should have been drop(lock_guard), mutex
// still locked
operation_that_requires_mutex_to_be_unlocked();
```
### Explanation
Calling `drop` or `forget` on a reference will only drop the reference itself, which is a no-op. It will not call the `drop` or `forget` method on the underlying referenced value, which is likely what was intended.
## `drop_copy` and `forget_copy`
The `drop_copy` and `forget_copy` lint checks for calls to `std::mem::forget` or `std::mem::drop` with a value that derives the Copy trait.
### Example
```rust
let x: i32 = 42; // i32 implements Copy
std::mem::forget(x) // A copy of x is passed to the function, leaving the
// original unaffected
```
### Explanation
Calling `std::mem::forget` [does nothing for types that implement Copy](https://doc.rust-lang.org/std/mem/fn.drop.html) since the value will be copied and moved into the function on invocation.
-----
Followed the instructions for uplift a clippy describe here: https://github.com/rust-lang/rust/pull/99696#pullrequestreview-1134072751
cc `@m-ou-se` (as T-libs-api leader because the uplifting was discussed in a recent meeting)
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| .. | ||
| 2229_closure_analysis | ||
| binder | ||
| closure-expected-type | ||
| add_semicolon_non_block_closure.rs | ||
| add_semicolon_non_block_closure.stderr | ||
| closure_cap_coerce_many_fail.rs | ||
| closure_cap_coerce_many_fail.stderr | ||
| closure_no_cap_coerce_many_check_pass.rs | ||
| closure_no_cap_coerce_many_run_pass.rs | ||
| closure_no_cap_coerce_many_unsafe_0.mir.stderr | ||
| closure_no_cap_coerce_many_unsafe_0.rs | ||
| closure_no_cap_coerce_many_unsafe_0.thir.stderr | ||
| closure_no_cap_coerce_many_unsafe_1.rs | ||
| closure_promotion.rs | ||
| closure-array-break-length.rs | ||
| closure-array-break-length.stderr | ||
| closure-bounds-cant-promote-superkind-in-struct.rs | ||
| closure-bounds-cant-promote-superkind-in-struct.stderr | ||
| closure-bounds-static-cant-capture-borrowed.rs | ||
| closure-bounds-static-cant-capture-borrowed.stderr | ||
| closure-bounds-subtype.rs | ||
| closure-bounds-subtype.stderr | ||
| closure-expected.rs | ||
| closure-expected.stderr | ||
| closure-immutable-outer-variable.fixed | ||
| closure-immutable-outer-variable.rs | ||
| closure-immutable-outer-variable.rs.fixed | ||
| closure-immutable-outer-variable.stderr | ||
| closure-move-sync.rs | ||
| closure-move-sync.stderr | ||
| closure-no-fn-1.rs | ||
| closure-no-fn-1.stderr | ||
| closure-no-fn-2.rs | ||
| closure-no-fn-2.stderr | ||
| closure-no-fn-3.rs | ||
| closure-no-fn-3.stderr | ||
| closure-no-fn-4.rs | ||
| closure-no-fn-4.stderr | ||
| closure-no-fn-5.rs | ||
| closure-no-fn-5.stderr | ||
| closure-referencing-itself-issue-25954.rs | ||
| closure-referencing-itself-issue-25954.stderr | ||
| closure-reform-bad.rs | ||
| closure-reform-bad.stderr | ||
| closure-return-type-mismatch.rs | ||
| closure-return-type-mismatch.stderr | ||
| closure-return-type-must-be-sized.rs | ||
| closure-return-type-must-be-sized.stderr | ||
| closure-wrong-kind.rs | ||
| closure-wrong-kind.stderr | ||
| coerce-unsafe-closure-to-unsafe-fn-ptr.mir.stderr | ||
| coerce-unsafe-closure-to-unsafe-fn-ptr.rs | ||
| coerce-unsafe-closure-to-unsafe-fn-ptr.thir.stderr | ||
| coerce-unsafe-to-closure.rs | ||
| coerce-unsafe-to-closure.stderr | ||
| deeply-nested_closures.rs | ||
| diverging-closure.rs | ||
| issue-868.rs | ||
| issue-6801.rs | ||
| issue-6801.stderr | ||
| issue-10398.rs | ||
| issue-10398.stderr | ||
| issue-23012-supertrait-signature-inference.rs | ||
| issue-41366.rs | ||
| issue-42463.rs | ||
| issue-46742.rs | ||
| issue-48109.rs | ||
| issue-52437.rs | ||
| issue-52437.stderr | ||
| issue-67123.rs | ||
| issue-67123.stderr | ||
| issue-68025.rs | ||
| issue-72408-nested-closures-exponential.rs | ||
| issue-78720.rs | ||
| issue-78720.stderr | ||
| issue-80313-mutable-borrow-in-closure.rs | ||
| issue-80313-mutable-borrow-in-closure.stderr | ||
| issue-80313-mutable-borrow-in-move-closure.rs | ||
| issue-80313-mutable-borrow-in-move-closure.stderr | ||
| issue-80313-mutation-in-closure.rs | ||
| issue-80313-mutation-in-closure.stderr | ||
| issue-80313-mutation-in-move-closure.rs | ||
| issue-80313-mutation-in-move-closure.stderr | ||
| issue-81700-mut-borrow.rs | ||
| issue-81700-mut-borrow.stderr | ||
| issue-82438-mut-without-upvar.rs | ||
| issue-82438-mut-without-upvar.stderr | ||
| issue-84044-drop-non-mut.rs | ||
| issue-84044-drop-non-mut.stderr | ||
| issue-84128.rs | ||
| issue-84128.stderr | ||
| issue-87461.rs | ||
| issue-87461.stderr | ||
| issue-87814-1.rs | ||
| issue-87814-2.rs | ||
| issue-90871.rs | ||
| issue-90871.stderr | ||
| issue-97607.rs | ||
| issue-99565.rs | ||
| issue-99565.stderr | ||
| issue-101696.rs | ||
| issue-102089-multiple-opaque-cast.rs | ||
| issue-109188.rs | ||
| issue-109188.stderr | ||
| local-type-mix.rs | ||
| local-type-mix.stderr | ||
| multiple-fn-bounds.rs | ||
| multiple-fn-bounds.stderr | ||
| old-closure-arg-call-as.rs | ||
| old-closure-arg.rs | ||
| old-closure-explicit-types.rs | ||
| old-closure-expr-precedence.rs | ||
| old-closure-expr-precedence.stderr | ||
| old-closure-expression-remove-semicolon.fixed | ||
| old-closure-expression-remove-semicolon.rs | ||
| old-closure-expression-remove-semicolon.stderr | ||
| old-closure-fn-coerce.rs | ||
| old-closure-iter-1.rs | ||
| old-closure-iter-2.rs | ||
| once-move-out-on-heap.rs | ||
| self-supertrait-bounds.rs | ||
| semistatement-in-lambda.rs | ||
| static-closures-with-nonstatic-return.rs | ||
| supertrait-hint-cycle-2.rs | ||
| supertrait-hint-cycle-3.rs | ||
| supertrait-hint-cycle.rs | ||
| supertrait-hint-references-assoc-ty.rs | ||
| thir-unsafeck-issue-85871.rs | ||