Fix mem::replace warning #124
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This PR fixes the following warning caused by not using the returned
value from `mem::replace`.
```
warning: unused return value of `std::mem::replace` that must be used
--> mockall_derive/src/lib.rs:519:21
|
519 | mem::replace(bt, new_bt);
| ^^^^^^^^^^^^^^^^^^^^^^^^^
|
= note: `#[warn(unused_must_use)]` on by default
= note: if you don't need the old value, you can
just assign the new value directly
warning: 1 warning emitted
```
joshleeb
commented
May 3, 2020
mockall_derive/src/lib.rs
Outdated
| @@ -516,7 +516,7 @@ fn supersuperfy(original: &Type, levels: i32) -> Type { | |||
| Type::BareFn(bfn) => { | |||
| if let ReturnType::Type(_, ref mut bt) = bfn.output { | |||
| let new_bt = Box::new(supersuperfy(bt.as_ref(), levels)); | |||
| mem::replace(bt, new_bt); | |||
| let _ = mem::replace(bt, new_bt); | |||
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Could instead replace this with mem::swap if you prefer 👍 but imho thought this was a bit more explicit
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Sorry - should've seen that we could get rid of mem::replace entirely
|
Thanks! But I haven't noticed this warning before. Is it a new one? What rustc version are you using? |
Warning displayed when running |
asomers
approved these changes
May 3, 2020
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This PR fixes the following warning caused by not using the returned
value from
mem::replace.