Preserve yield position during pretty printing

1 files changed, 12 insertions, 2 deletions

diff --git a/compiler/rustc_ast_pretty/src/pprust/state/expr.rs b/compiler/rustc_ast_pretty/src/pprust/state/expr.rs
index e3c41f117ab..9e53ed41c46 100644
--- a/compiler/rustc_ast_pretty/src/pprust/state/expr.rs
+++ b/compiler/rustc_ast_pretty/src/pprust/state/expr.rs
@@ -8,7 +8,7 @@ use rustc_ast::util::literal::escape_byte_str_symbol;
 use rustc_ast::util::parser::{self, ExprPrecedence, Fixity};
 use rustc_ast::{
     self as ast, BlockCheckMode, FormatAlignment, FormatArgPosition, FormatArgsPiece, FormatCount,
-    FormatDebugHex, FormatSign, FormatTrait, token,
+    FormatDebugHex, FormatSign, FormatTrait, YieldKind, token,
 };
 
 use crate::pp::Breaks::Inconsistent;
@@ -761,7 +761,7 @@ impl<'a> State<'a> {
                 self.print_expr(e, FixupContext::default());
                 self.pclose();
             }
-            ast::ExprKind::Yield(e) => {
+            ast::ExprKind::Yield(e, YieldKind::Prefix) => {
                 self.word("yield");
 
                 if let Some(expr) = e {
@@ -773,6 +773,16 @@ impl<'a> State<'a> {
                     );
                 }
             }
+            ast::ExprKind::Yield(e, YieldKind::Postfix) => {
+                // it's not possible to have a postfix yield with no expression.
+                let e = e.as_ref().unwrap();
+                self.print_expr_cond_paren(
+                    e,
+                    e.precedence() < ExprPrecedence::Unambiguous,
+                    fixup.leftmost_subexpression_with_dot(),
+                );
+                self.word(".yield");
+            }
             ast::ExprKind::Try(e) => {
                 self.print_expr_cond_paren(
                     e,