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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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| .. | ||
| diagnostics | ||
| match | ||
| migrations | ||
| optimization | ||
| run_pass | ||
| array_subslice.rs | ||
| array_subslice.stderr | ||
| arrays-completely-captured.rs | ||
| arrays-completely-captured.stderr | ||
| bad-pattern.rs | ||
| bad-pattern.stderr | ||
| by_value.rs | ||
| by_value.stderr | ||
| capture-analysis-1.rs | ||
| capture-analysis-1.stderr | ||
| capture-analysis-2.rs | ||
| capture-analysis-2.stderr | ||
| capture-analysis-3.rs | ||
| capture-analysis-3.stderr | ||
| capture-analysis-4.rs | ||
| capture-analysis-4.stderr | ||
| capture-disjoint-field-struct.rs | ||
| capture-disjoint-field-struct.stderr | ||
| capture-disjoint-field-tuple.rs | ||
| capture-disjoint-field-tuple.stderr | ||
| capture-enum-field.rs | ||
| capture-enums.rs | ||
| capture-enums.stderr | ||
| deep-multilevel-struct.rs | ||
| deep-multilevel-struct.stderr | ||
| deep-multilevel-tuple.rs | ||
| deep-multilevel-tuple.stderr | ||
| destructure_patterns.rs | ||
| destructure_patterns.stderr | ||
| feature-gate-capture_disjoint_fields.rs | ||
| feature-gate-capture_disjoint_fields.stderr | ||
| filter-on-struct-member.rs | ||
| filter-on-struct-member.stderr | ||
| issue_88118.rs | ||
| issue-87378.rs | ||
| issue-87378.stderr | ||
| issue-87987.rs | ||
| issue-87987.stderr | ||
| issue-88118-2.rs | ||
| issue-88118-2.stderr | ||
| issue-88476.rs | ||
| issue-88476.stderr | ||
| issue-89606.rs | ||
| issue-90465.fixed | ||
| issue-90465.rs | ||
| issue-90465.stderr | ||
| issue-92724-needsdrop-query-cycle.rs | ||
| move_closure.rs | ||
| move_closure.stderr | ||
| multilevel-path-1.rs | ||
| multilevel-path-1.stderr | ||
| multilevel-path-2.rs | ||
| multilevel-path-2.stderr | ||
| nested-closure.rs | ||
| nested-closure.stderr | ||
| path-with-array-access.rs | ||
| path-with-array-access.stderr | ||
| preserve_field_drop_order2.rs | ||
| preserve_field_drop_order2.twenty_eighteen.run.stdout | ||
| preserve_field_drop_order2.twenty_twentyone.run.stdout | ||
| preserve_field_drop_order.rs | ||
| preserve_field_drop_order.stderr | ||
| repr_packed.rs | ||
| repr_packed.stderr | ||
| simple-struct-min-capture.rs | ||
| simple-struct-min-capture.stderr | ||
| unsafe_ptr.rs | ||
| unsafe_ptr.stderr | ||
| wild_patterns.rs | ||
| wild_patterns.stderr | ||