Fix [needless_return] false negative
#13214
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…ws a value Fixes rust-lang#12907 changelog: Fix [`needless_return`] false negative when returned expression borrows a value
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Looks good to me, thanks! Let's just wait for the assigned reviewer to take a look before approving. |
| fn issue12907() -> String { | ||
| return "".split("").next().unwrap().to_string(); | ||
| } | ||
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I think this just needs a test for the mentioned RefCell or any other type that fails to compile. But I think the significant drop check is adequate
There is the rustc_insigificant_dtor attribute. (I didn't even know this existed before checking.) This is applied to certain types like Rc, HashMap, and array::IntoIter. Not sure whether this attribute changes the behavior (i.e., compiling would succeed) but it'd be a good idea to check.
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I think this just needs a test for the mentioned
RefCellor any other type that fails to compile. But I think the significant drop check is adequate
So should i delete the test then?
Not sure whether this attribute changes the behavior (i.e., compiling would succeed) but it'd be a good idea to check.
Yes, it compiles with the rustc_insigificant_dtor attribute and the lint is triggered.
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No I meant the only change it needs
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There is already a very similar test to the one mentioned:
fn temporary_outlives_local() -> String {
let x = RefCell::<String>::default();
return x.borrow().clone();
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Yeah that does the same thing 👍 missed that before
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Thank you! @bors r+ |
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☀️ Test successful - checks-action_dev_test, checks-action_remark_test, checks-action_test |
5 participants
Fixes #12907
changelog: Fix [
needless_return] false negative when returned expression borrows a value.