bjoernager/rust
bjoernager/rust
1
Fork 0
Code Activity

tweak "make mut" spans (No. 2)

Browse source
This commit is contained in:
Ezra Shaw 2023-04-19 19:29:28 +12:00 • committed by Ezra Shaw
parent fd8aa5ec7d
commit 9624d2b08e
No known key found for this signature in database
GPG key ID: 5156CF5845150B0D
7 changed files with 36 additions and 30 deletions
Download patch file Download diff file Expand all files Collapse all files

48
compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs
View file

@ -1241,35 +1241,41 @@ fn suggest_ampmut<'tcx>(
}
}
let (suggestibility, highlight_span) = match opt_ty_info {
let (binding_exists, span) = match opt_ty_info {
// if this is a variable binding with an explicit type,
// try to highlight that for the suggestion.
// then we will suggest changing it to be mutable.
// this is `Applicability::MachineApplicable`.
Some(ty_span) => (true, ty_span),
// otherwise, just highlight the span associated with
// the (MIR) LocalDecl.
// otherwise, we'll suggest *adding* an annotated type, we'll suggest
// the RHS's type for that.
// this is `Applicability::HasPlaceholders`.
None => (false, local_decl.source_info.span),
};
if let Ok(src) = tcx.sess.source_map().span_to_snippet(highlight_span)
&& let (true, Some(ws_pos)) = (src.starts_with("&'"), src.find(char::is_whitespace))
// if the binding already exists and is a reference with a explicit
// lifetime, then we can suggest adding ` mut`. this is special-cased from
// the path without a explicit lifetime.
if let Ok(src) = tcx.sess.source_map().span_to_snippet(span)
&& src.starts_with("&'")
// note that `& 'a T` is invalid so this is correct.
&& let Some(ws_pos) = src.find(char::is_whitespace)
{
let lt_name = &src[1..ws_pos];
let ty = &src[ws_pos..];
return (true, highlight_span, format!("&{lt_name} mut{ty}"));
let span = span.with_lo(span.lo() + BytePos(ws_pos as u32)).shrink_to_lo();
(true, span, " mut".to_owned())
} else {
let ty_mut = local_decl.ty.builtin_deref(true).unwrap();
assert_eq!(ty_mut.mutbl, hir::Mutability::Not);
(
binding_exists,
span,
if local_decl.ty.is_ref() {
format!("&mut {}", ty_mut.ty)
} else {
format!("*mut {}", ty_mut.ty)
},
)
}
let ty_mut = local_decl.ty.builtin_deref(true).unwrap();
assert_eq!(ty_mut.mutbl, hir::Mutability::Not);
(
suggestibility,
highlight_span,
if local_decl.ty.is_ref() {
format!("&mut {}", ty_mut.ty)
} else {
format!("*mut {}", ty_mut.ty)
},
)
}
fn is_closure_or_generator(ty: Ty<'_>) -> bool {