diff options
| -rw-r--r-- | compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs | 3 | ||||
| -rw-r--r-- | tests/ui/return/tail-expr-as-potential-return.rs | 36 | ||||
| -rw-r--r-- | tests/ui/return/tail-expr-as-potential-return.stderr | 33 |
3 files changed, 56 insertions, 16 deletions
diff --git a/compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs b/compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs index 1138642c56d..f4f3f243167 100644 --- a/compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs +++ b/compiler/rustc_hir_typeck/src/fn_ctxt/checks.rs @@ -2042,7 +2042,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> { } if block_num > 1 && found_semi { err.span_suggestion_verbose( - span.shrink_to_lo(), + // use the span of the *whole* expr + self.tcx.hir().span(binding_hir_id).shrink_to_lo(), "you might have meant to return this to infer its type parameters", "return ", Applicability::MaybeIncorrect, diff --git a/tests/ui/return/tail-expr-as-potential-return.rs b/tests/ui/return/tail-expr-as-potential-return.rs index 37dee1c19db..11ecddb049b 100644 --- a/tests/ui/return/tail-expr-as-potential-return.rs +++ b/tests/ui/return/tail-expr-as-potential-return.rs @@ -1,3 +1,5 @@ +//@ edition:2018 + // > Suggest returning tail expressions that match return type // > // > Some newcomers are confused by the behavior of tail expressions, @@ -8,24 +10,24 @@ // // This test was amended to also serve as a regression test for #92308, where // this suggestion would not trigger with async functions. -// -//@ edition:2018 fn main() { } fn foo(x: bool) -> Result<f64, i32> { if x { - Err(42) //~ ERROR mismatched types - //| HELP you might have meant to return this value + Err(42) + //~^ ERROR mismatched types + //~| HELP you might have meant to return this value } Ok(42.0) } async fn bar(x: bool) -> Result<f64, i32> { if x { - Err(42) //~ ERROR mismatched types - //| HELP you might have meant to return this value + Err(42) + //~^ ERROR mismatched types + //~| HELP you might have meant to return this value } Ok(42.0) } @@ -40,8 +42,26 @@ impl<T> Identity for T { async fn foo2() -> i32 { if true { - 1i32 //~ ERROR mismatched types - //| HELP you might have meant to return this value + 1i32 + //~^ ERROR mismatched types + //~| HELP you might have meant to return this value } 0 } + +struct Receiver; +impl Receiver { + fn generic<T>(self) -> Option<T> { + None + } +} +fn method() -> Option<i32> { + if true { + Receiver.generic(); + //~^ ERROR type annotations needed + //~| HELP consider specifying the generic argument + //~| HELP you might have meant to return this to infer its type parameters + } + + None +} diff --git a/tests/ui/return/tail-expr-as-potential-return.stderr b/tests/ui/return/tail-expr-as-potential-return.stderr index ccb208fc6c4..635a9e06633 100644 --- a/tests/ui/return/tail-expr-as-potential-return.stderr +++ b/tests/ui/return/tail-expr-as-potential-return.stderr @@ -1,10 +1,11 @@ error[E0308]: mismatched types - --> $DIR/tail-expr-as-potential-return.rs:27:9 + --> $DIR/tail-expr-as-potential-return.rs:28:9 | LL | / if x { LL | | Err(42) | | ^^^^^^^ expected `()`, found `Result<_, {integer}>` -LL | | //| HELP you might have meant to return this value +LL | | +LL | | LL | | } | |_____- expected this to be `()` | @@ -16,12 +17,13 @@ LL | return Err(42); | ++++++ + error[E0308]: mismatched types - --> $DIR/tail-expr-as-potential-return.rs:43:9 + --> $DIR/tail-expr-as-potential-return.rs:45:9 | LL | / if true { LL | | 1i32 | | ^^^^ expected `()`, found `i32` -LL | | //| HELP you might have meant to return this value +LL | | +LL | | LL | | } | |_____- expected this to be `()` | @@ -36,7 +38,8 @@ error[E0308]: mismatched types LL | / if x { LL | | Err(42) | | ^^^^^^^ expected `()`, found `Result<_, {integer}>` -LL | | //| HELP you might have meant to return this value +LL | | +LL | | LL | | } | |_____- expected this to be `()` | @@ -47,6 +50,22 @@ help: you might have meant to return this value LL | return Err(42); | ++++++ + -error: aborting due to 3 previous errors +error[E0282]: type annotations needed + --> $DIR/tail-expr-as-potential-return.rs:60:18 + | +LL | Receiver.generic(); + | ^^^^^^^ cannot infer type of the type parameter `T` declared on the method `generic` + | +help: consider specifying the generic argument + | +LL | Receiver.generic::<T>(); + | +++++ +help: you might have meant to return this to infer its type parameters + | +LL | return Receiver.generic(); + | ++++++ + +error: aborting due to 4 previous errors -For more information about this error, try `rustc --explain E0308`. +Some errors have detailed explanations: E0282, E0308. +For more information about an error, try `rustc --explain E0282`. |