Add reborrow suggestion when mutable reference is moved in a for loop

This commit is contained in:
Giacomo Stevanato 2021-04-06 21:39:44 +02:00
parent 354cc751b7
commit 7f823e5bbd

View File

@ -264,7 +264,24 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
if let Some(DesugaringKind::ForLoop(_)) = move_span.desugaring_kind() {
let sess = self.infcx.tcx.sess;
if let Ok(snippet) = sess.source_map().span_to_snippet(move_span) {
let ty = used_place.ty(self.body, self.infcx.tcx).ty;
// If we have a `&mut` ref, we need to reborrow.
if let ty::Ref(_, _, hir::Mutability::Mut) = ty.kind() {
// If we are in a loop this will be suggested later.
if !is_loop_move {
err.span_suggestion_verbose(
move_span.shrink_to_lo(),
&format!(
"consider creating a fresh reborrow of {} here",
self.describe_place(moved_place.as_ref())
.map(|n| format!("`{}`", n))
.unwrap_or_else(|| "the mutable reference".to_string()),
),
format!("&mut *"),
Applicability::MachineApplicable,
);
}
} else if let Ok(snippet) = sess.source_map().span_to_snippet(move_span) {
err.span_suggestion(
move_span,
"consider borrowing to avoid moving into the for loop",