mikros/rust
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Fix false negative on Result<(), ()>

Browse Source
This commit is contained in:
blyxyas 2023-04-03 16:01:30 +02:00
parent d602743558
commit a37eb4dfc9
No known key found for this signature in database
GPG Key ID: 4D38170B5A2FC334
2 changed files with 20 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
clippy_lints/src/functions/must_use.rs
View File

@ -3,6 +3,7 @@ use rustc_ast::ast::Attribute;
use rustc_errors::Applicability;
use rustc_hir::def_id::DefIdSet;
use rustc_hir::{self as hir, def::Res, QPath};
use rustc_infer::infer::TyCtxtInferExt;
use rustc_lint::{LateContext, LintContext};
use rustc_middle::{
lint::in_external_macro,
@ -113,7 +114,16 @@ fn check_needless_must_use(
diag.span_suggestion(attr.span, "remove the attribute", "", Applicability::MachineApplicable);
},
);
} else if attr.value_str().is_none() && is_must_use_ty(cx, return_ty(cx, item_id)) && !sig.header.is_async() {
} else if attr.value_str().is_none() && is_must_use_ty(cx, return_ty(cx, item_id)) {
// Ignore async functions unless Future::Output type is a must_use type
if sig.header.is_async() {
let infcx = cx.tcx.infer_ctxt().build();
if let Some(future_ty) = infcx.get_impl_future_output_ty(return_ty(cx, item_id))
&& !is_must_use_ty(cx, future_ty) {
return;
}
}
span_lint_and_help(
cx,
DOUBLE_MUST_USE,

10
tests/ui/double_must_use.stderr
View File

@ -23,5 +23,13 @@ LL | pub fn must_use_array() -> [Result<(), ()>; 1] {
|
= help: either add some descriptive text or remove the attribute
error: aborting due to 3 previous errors
error: this function has an empty `#[must_use]` attribute, but returns a type already marked as `#[must_use]`
--> $DIR/double_must_use.rs:31:1
|
LL | async fn async_must_use_result() -> Result<(), ()> {
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
= help: either add some descriptive text or remove the attribute
error: aborting due to 4 previous errors