diff --git a/compiler/rustc_middle/src/ty/diagnostics.rs b/compiler/rustc_middle/src/ty/diagnostics.rs index 99a3d4c7fe4f7..7d950b79cdd8d 100644 --- a/compiler/rustc_middle/src/ty/diagnostics.rs +++ b/compiler/rustc_middle/src/ty/diagnostics.rs @@ -512,7 +512,7 @@ pub fn suggest_constraining_type_params<'a>( }; err.span_suggestion_verbose(span, msg, suggestion, applicability); - } else { + } else if suggestions.len() > 1 { err.multipart_suggestion_verbose( "consider restricting type parameters", suggestions.into_iter().map(|(span, suggestion, _)| (span, suggestion)).collect(), diff --git a/src/test/ui/suggestions/constrain-suggest-ice.rs b/src/test/ui/suggestions/constrain-suggest-ice.rs new file mode 100644 index 0000000000000..69b874bed1b90 --- /dev/null +++ b/src/test/ui/suggestions/constrain-suggest-ice.rs @@ -0,0 +1,11 @@ +struct Bug{ //~ ERROR parameter `S` is never used [E0392] + A: [(); { + let x: [u8; Self::W] = [0; Self::W]; //~ ERROR generic `Self` types are currently not permitted in anonymous constants + //~^ ERROR generic `Self` types are currently not permitted in anonymous constants + //~^^ ERROR the size for values of type `S` cannot be known at compilation time [E0277] + F //~ ERROR cannot find value `F` in this scope [E0425] + } +} //~ ERROR mismatched closing delimiter: `}` +//~^ ERROR mismatched closing delimiter: `}` + +fn main() {} diff --git a/src/test/ui/suggestions/constrain-suggest-ice.stderr b/src/test/ui/suggestions/constrain-suggest-ice.stderr new file mode 100644 index 0000000000000..477eb2786799a --- /dev/null +++ b/src/test/ui/suggestions/constrain-suggest-ice.stderr @@ -0,0 +1,81 @@ +error: mismatched closing delimiter: `}` + --> $DIR/constrain-suggest-ice.rs:2:8 + | +LL | struct Bug{ + | - closing delimiter possibly meant for this +LL | A: [(); { + | ^ unclosed delimiter +... +LL | } + | ^ mismatched closing delimiter + +error: mismatched closing delimiter: `}` + --> $DIR/constrain-suggest-ice.rs:2:8 + | +LL | struct Bug{ + | - closing delimiter possibly meant for this +LL | A: [(); { + | ^ unclosed delimiter +... +LL | } + | ^ mismatched closing delimiter + +error[E0425]: cannot find value `F` in this scope + --> $DIR/constrain-suggest-ice.rs:6:9 + | +LL | F + | ^ + | +help: a local variable with a similar name exists + | +LL | x + | ~ +help: you might be missing a type parameter + | +LL | struct Bug{ + | +++ + +error: generic `Self` types are currently not permitted in anonymous constants + --> $DIR/constrain-suggest-ice.rs:3:21 + | +LL | let x: [u8; Self::W] = [0; Self::W]; + | ^^^^ + +error: generic `Self` types are currently not permitted in anonymous constants + --> $DIR/constrain-suggest-ice.rs:3:36 + | +LL | let x: [u8; Self::W] = [0; Self::W]; + | ^^^^ + +error[E0277]: the size for values of type `S` cannot be known at compilation time + --> $DIR/constrain-suggest-ice.rs:3:36 + | +LL | struct Bug{ + | - this type parameter needs to be `std::marker::Sized` +LL | A: [(); { +LL | let x: [u8; Self::W] = [0; Self::W]; + | ^^^^^^^ doesn't have a size known at compile-time + | +note: required by a bound in `Bug` + --> $DIR/constrain-suggest-ice.rs:1:12 + | +LL | struct Bug{ + | ^ required by this bound in `Bug` +help: consider relaxing the implicit `Sized` restriction + | +LL | struct Bug{ + | ++++++++ + +error[E0392]: parameter `S` is never used + --> $DIR/constrain-suggest-ice.rs:1:12 + | +LL | struct Bug{ + | ^ unused parameter + | + = help: consider removing `S`, referring to it in a field, or using a marker such as `PhantomData` + = help: if you intended `S` to be a const parameter, use `const S: usize` instead + +error: aborting due to 7 previous errors + +Some errors have detailed explanations: E0277, E0392, E0425. +For more information about an error, try `rustc --explain E0277`.