nordic-dev.net/rust
nordic-dev.net/rust
2
0
Fork 0
mirror of https://github.com/rust-lang/rust.git synced 2024-11-22 14:55:26 +00:00
Code Issues Packages Projects Releases Wiki Activity

Add note about wrapping in braces

Browse Source 
Previously it was not clear why this errored or if it was even supported, as there was no
diagnostic that suggested wrapping it in braces.

Thus, add a simple diagnostic that suggests wrapping enum variants in braces.
This commit is contained in:
kadmin 2022-12-30 05:09:09 +00:00
parent 2c7536eaae
commit 077fae94a1
3 changed files with 70 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

29
compiler/rustc_hir_analysis/src/astconv/mod.rs
View File

@ -1199,17 +1199,26 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
(_, _) => {
let got = if let Some(_) = term.ty() { "type" } else { "constant" };
let expected = def_kind.descr(assoc_item_def_id);
let reported = tcx
.sess
.struct_span_err(
let mut err = tcx.sess.struct_span_err(
binding.span,
&format!("expected {expected} bound, found {got}"),
);
err.span_note(
tcx.def_span(assoc_item_def_id),
&format!("{expected} defined here"),
);
if let hir::def::DefKind::AssocConst = def_kind
&& let Some(t) = term.ty() && (t.is_enum() || t.references_error())
&& tcx.features().associated_const_equality {
err.span_suggestion(
binding.span,
&format!("expected {expected} bound, found {got}"),
)
.span_note(
tcx.def_span(assoc_item_def_id),
&format!("{expected} defined here"),
)
.emit();
"if equating a const, try wrapping with braces",
format!("{} = {{ const }}", binding.item_name),
Applicability::HasPlaceholders,
);
}
let reported = err.emit();
term = match def_kind {
hir::def::DefKind::AssocTy => {
tcx.ty_error_with_guaranteed(reported).into()

18
src/test/ui/const-generics/assoc_const_eq_diagnostic.rs Normal file
View File

@ -0,0 +1,18 @@
#![feature(associated_const_equality)]
pub enum Mode {
Cool,
}
pub trait Parse {
const MODE: Mode;
}
pub trait CoolStuff: Parse<MODE = Mode::Cool> {}
//~^ ERROR expected associated constant bound
//~| ERROR expected type
fn no_help() -> Mode::Cool {}
//~^ ERROR expected type, found variant
fn main() {}

33
src/test/ui/const-generics/assoc_const_eq_diagnostic.stderr Normal file
View File

@ -0,0 +1,33 @@
error[E0573]: expected type, found variant `Mode::Cool`
--> $DIR/assoc_const_eq_diagnostic.rs:11:35
|
LL | pub trait CoolStuff: Parse<MODE = Mode::Cool> {}
| ^^^^^^^^^^
| |
| not a type
| help: try using the variant's enum: `Mode`
error[E0573]: expected type, found variant `Mode::Cool`
--> $DIR/assoc_const_eq_diagnostic.rs:15:17
|
LL | fn no_help() -> Mode::Cool {}
| ^^^^^^^^^^
| |
| not a type
| help: try using the variant's enum: `Mode`
error: expected associated constant bound, found type
--> $DIR/assoc_const_eq_diagnostic.rs:11:28
|
LL | pub trait CoolStuff: Parse<MODE = Mode::Cool> {}
| ^^^^^^^^^^^^^^^^^ help: if equating a const, try wrapping with braces: `MODE = { const }`
|
note: associated constant defined here
--> $DIR/assoc_const_eq_diagnostic.rs:8:5
|
LL | const MODE: Mode;
| ^^^^^^^^^^^^^^^^
error: aborting due to 3 previous errors
For more information about this error, try `rustc --explain E0573`.