nordic-dev.net/rust
nordic-dev.net/rust
2
0
Fork 0
mirror of https://github.com/rust-lang/rust.git synced 2024-11-25 16:24:46 +00:00
Code Issues Packages Projects Releases Wiki Activity

Provide structured suggestion for removal of &mut

Browse Source
This commit is contained in:
Esteban Kuber 2021-08-09 11:05:50 +00:00
parent e4368de7b1
commit a6af6d6506
3 changed files with 28 additions and 14 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

22
compiler/rustc_mir/src/borrow_check/diagnostics/mutability_errors.rs
View File

@ -12,7 +12,7 @@ use rustc_middle::{
};
use rustc_span::source_map::DesugaringKind;
use rustc_span::symbol::{kw, Symbol};
use rustc_span::Span;
use rustc_span::{BytePos, Span};
use crate::borrow_check::diagnostics::BorrowedContentSource;
use crate::borrow_check::MirBorrowckCtxt;
@ -278,7 +278,25 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
);
}
}
err.span_help(source_info.span, "try removing `&mut` here");
if let Ok(snippet) =
self.infcx.tcx.sess.source_map().span_to_snippet(source_info.span)
{
if snippet.starts_with("&mut ") {
// We don't have access to the HIR to get accurate spans, but we can
// give a best effort structured suggestion.
err.span_suggestion_verbose(
source_info.span.with_hi(source_info.span.lo() + BytePos(5)),
"try removing `&mut` here",
String::new(),
Applicability::MachineApplicable,
);
} else {
// This can occur with things like `(&mut self).foo()`.
err.span_help(source_info.span, "try removing `&mut` here");
}
} else {
err.span_help(source_info.span, "try removing `&mut` here");
}
} else if decl.mutability == Mutability::Not
&& !matches!(
decl.local_info,

15
src/test/ui/borrowck/mut-borrow-of-mut-ref.stderr
View File

@ -10,10 +10,9 @@ note: the binding is already a mutable borrow
LL | pub fn f(b: &mut i32) {
| ^^^^^^^^
help: try removing `&mut` here
--> $DIR/mut-borrow-of-mut-ref.rs:7:7
|
LL | h(&mut b);
| ^^^^^^
LL | h(b);
| --
error[E0596]: cannot borrow `b` as mutable, as it is not declared as mutable
--> $DIR/mut-borrow-of-mut-ref.rs:11:12
@ -27,10 +26,9 @@ note: the binding is already a mutable borrow
LL | pub fn f(b: &mut i32) {
| ^^^^^^^^
help: try removing `&mut` here
--> $DIR/mut-borrow-of-mut-ref.rs:11:12
|
LL | g(&mut &mut b);
| ^^^^^^
LL | g(&mut b);
| --
error[E0596]: cannot borrow `b` as mutable, as it is not declared as mutable
--> $DIR/mut-borrow-of-mut-ref.rs:18:12
@ -44,10 +42,9 @@ note: the binding is already a mutable borrow
LL | pub fn g(b: &mut i32) {
| ^^^^^^^^
help: try removing `&mut` here
--> $DIR/mut-borrow-of-mut-ref.rs:18:12
|
LL | h(&mut &mut b);
| ^^^^^^
LL | h(&mut b);
| --
error[E0596]: cannot borrow `f` as mutable, as it is not declared as mutable
--> $DIR/mut-borrow-of-mut-ref.rs:35:5

5
src/test/ui/did_you_mean/issue-34126.stderr
View File

@ -10,10 +10,9 @@ note: the binding is already a mutable borrow
LL | fn start(&mut self) {
| ^^^^^^^^^
help: try removing `&mut` here
--> $DIR/issue-34126.rs:6:18
|
LL | self.run(&mut self);
| ^^^^^^^^^
LL | self.run(self);
| --
error[E0502]: cannot borrow `self` as mutable because it is also borrowed as immutable
--> $DIR/issue-34126.rs:6:18