Move condition out of maybe_recover_from_question_mark.

Author: nnethercote

compiler/rustc_parse/src/parser/diagnostics.rs

@@ -1,5 +1,5 @@
 use super::pat::Expected;
-use super::ty::{AllowPlus, RecoverQuestionMark};
+use super::ty::AllowPlus;
 use super::{
     BlockMode, CommaRecoveryMode, Parser, PathStyle, RecoverColon, RecoverComma, Restrictions,
     SemiColonMode, SeqSep, TokenExpectType, TokenType,
@@ -1248,14 +1248,7 @@ impl<'a> Parser<'a> {
     }
 
     /// Swift lets users write `Ty?` to mean `Option<Ty>`. Parse the construct and recover from it.
-    pub(super) fn maybe_recover_from_question_mark(
-        &mut self,
-        ty: P<Ty>,
-        recover_question_mark: RecoverQuestionMark,
-    ) -> P<Ty> {
-        if let RecoverQuestionMark::No = recover_question_mark {
-            return ty;
-        }
+    pub(super) fn maybe_recover_from_question_mark(&mut self, ty: P<Ty>) -> P<Ty> {
         if self.token == token::Question {
             self.bump();
             self.struct_span_err(self.prev_token.span, "invalid `?` in type")

compiler/rustc_parse/src/parser/ty.rs

@@ -312,12 +312,14 @@ impl<'a> Parser<'a> {
         };
 
         let span = lo.to(self.prev_token.span);
-        let ty = self.mk_ty(span, kind);
+        let mut ty = self.mk_ty(span, kind);
 
         // Try to recover from use of `+` with incorrect priority.
         self.maybe_report_ambiguous_plus(allow_plus, impl_dyn_multi, &ty);
         self.maybe_recover_from_bad_type_plus(allow_plus, &ty)?;
-        let ty = self.maybe_recover_from_question_mark(ty, recover_question_mark);
+        if let RecoverQuestionMark::Yes = recover_question_mark {
+            ty = self.maybe_recover_from_question_mark(ty);
+        }
         if allow_qpath_recovery { self.maybe_recover_from_bad_qpath(ty) } else { Ok(ty) }
     }