bjoernager/rust
bjoernager/rust
1
Fork 0
Code Issues Pull requests Activity

Rollup merge of #102927 - compiler-errors:let, r=davidtwco

Browse source 
Fix `let` keyword removal suggestion in structs

(1.) Fixes a bug where, given this code:
```rust
struct Foo {
  let x: i32,
}
```

We were parsing the field name as `let` instead of `x`, which causes issues later on in the type-checking phase.

(2.) Also, suggestions for `let: i32` as a field regressed, displaying this extra `help:` which is removed by this PR

```
help: remove the let, the `let` keyword is not allowed in struct field definitions
  |
2 -     let: i32,
2 +     : i32,
```

(3.) Makes the suggestion text a bit more succinct, since we don't need to re-explain that `let` is not allowed in this position (since it's in a note that follows). This causes the suggestion to render inline as well.

cc `@gimbles,` this addresses a few nits I mentioned in your PR.
This commit is contained in:
Dylan DPC 2022-10-12 22:13:26 +05:30 • committed by GitHub
commit a9a5529eac
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
6 changed files with 81 additions and 12 deletions
Download patch file Download diff file Expand all files Collapse all files

17
compiler/rustc_parse/src/parser/item.rs
View file

@ -1789,20 +1789,25 @@ impl<'a> Parser<'a> {
}
} else {
let mut err = self.expected_ident_found();
if let Some((ident, _)) = self.token.ident() && ident.as_str() == "let" {
self.bump(); // `let`
let span = self.prev_token.span.until(self.token.span);
if self.eat_keyword_noexpect(kw::Let)
&& let removal_span = self.prev_token.span.until(self.token.span)
&& let Ok(ident) = self.parse_ident_common(false)
// Cancel this error, we don't need it.
.map_err(|err| err.cancel())
&& self.token.kind == TokenKind::Colon
{
err.span_suggestion(
span,
"remove the let, the `let` keyword is not allowed in struct field definitions",
removal_span,
"remove this `let` keyword",
String::new(),
Applicability::MachineApplicable,
);
err.note("the `let` keyword is not allowed in `struct` fields");
err.note("see <https://doc.rust-lang.org/book/ch05-01-defining-structs.html> for more information");
err.emit();
self.bump();
return Ok(ident);
} else {
self.restore_snapshot(snapshot);
}
err
};