Auto merge of #51052 - nikomatsakis:obsolete-arrow, r=petrochenkov

restore emplacement syntax (obsolete)

Fix https://github.com/rust-lang/rust/issues/50832

r? @petrochenkov

1 files changed, 13 insertions, 0 deletions

diff --git a/src/libsyntax/parse/parser.rs b/src/libsyntax/parse/parser.rs
index 5a3e5586495..2c246d75b52 100644
--- a/src/libsyntax/parse/parser.rs
+++ b/src/libsyntax/parse/parser.rs
@@ -2839,6 +2839,17 @@ impl<'a> Parser<'a> {
                 let (span, e) = self.interpolated_or_expr_span(e)?;
                 (lo.to(span), ExprKind::AddrOf(m, e))
             }
+            token::Ident(..) if self.token.is_keyword(keywords::In) => {
+                self.bump();
+                let place = self.parse_expr_res(
+                    Restrictions::NO_STRUCT_LITERAL,
+                    None,
+                )?;
+                let blk = self.parse_block()?;
+                let span = blk.span;
+                let blk_expr = self.mk_expr(span, ExprKind::Block(blk, None), ThinVec::new());
+                (lo.to(span), ExprKind::ObsoleteInPlace(place, blk_expr))
+            }
             token::Ident(..) if self.token.is_keyword(keywords::Box) => {
                 self.bump();
                 let e = self.parse_prefix_expr(None);
@@ -3042,6 +3053,8 @@ impl<'a> Parser<'a> {
                 }
                 AssocOp::Assign =>
                     self.mk_expr(span, ExprKind::Assign(lhs, rhs), ThinVec::new()),
+                AssocOp::ObsoleteInPlace =>
+                    self.mk_expr(span, ExprKind::ObsoleteInPlace(lhs, rhs), ThinVec::new()),
                 AssocOp::AssignOp(k) => {
                     let aop = match k {
                         token::Plus =>    BinOpKind::Add,