Use bool in favor of Option<()> for diagnostics

compiler/rustc_parse/src/errors.rs

@@ -913,7 +913,7 @@ pub(crate) struct InvalidLiteralSuffixOnTupleIndex {
     #[help(parse_tuple_exception_line_1)]
     #[help(parse_tuple_exception_line_2)]
     #[help(parse_tuple_exception_line_3)]
-    pub exception: Option<()>,
+    pub exception: bool,
 }
 
 #[derive(Diagnostic)]
@@ -1299,7 +1299,7 @@ pub(crate) struct ComparisonOperatorsCannotBeChained {
     pub suggest_turbofish: Option<Span>,
     #[help(parse_sugg_turbofish_syntax)]
     #[help(parse_sugg_parentheses_for_function_args)]
-    pub help_turbofish: Option<()>,
+    pub help_turbofish: bool,
     #[subdiagnostic]
     pub chaining_sugg: Option<ComparisonOperatorsCannotBeChainedSugg>,
 }
@@ -1578,7 +1578,7 @@ pub(crate) struct PathSingleColon {
     pub suggestion: Span,
 
     #[note(parse_type_ascription_removed)]
-    pub type_ascription: Option<()>,
+    pub type_ascription: bool,
 }
 
 #[derive(Diagnostic)]
@@ -1589,7 +1589,7 @@ pub(crate) struct ColonAsSemi {
     pub span: Span,
 
     #[note(parse_type_ascription_removed)]
-    pub type_ascription: Option<()>,
+    pub type_ascription: bool,
 }
 
 #[derive(Diagnostic)]
@@ -2462,7 +2462,7 @@ pub(crate) struct TrailingVertNotAllowed {
     pub start: Option<Span>,
     pub token: Token,
     #[note(parse_note_pattern_alternatives_use_single_vert)]
-    pub note_double_vert: Option<()>,
+    pub note_double_vert: bool,
 }
 
 #[derive(Diagnostic)]
@@ -2894,7 +2894,7 @@ pub(crate) struct BadItemKind {
     pub descr: &'static str,
     pub ctx: &'static str,
     #[help]
-    pub help: Option<()>,
+    pub help: bool,
 }
 
 #[derive(Diagnostic)]

compiler/rustc_parse/src/parser/diagnostics.rs

@@ -1403,7 +1403,7 @@ impl<'a> Parser<'a> {
                 let mut err = ComparisonOperatorsCannotBeChained {
                     span: vec![op.span, self.prev_token.span],
                     suggest_turbofish: None,
-                    help_turbofish: None,
+                    help_turbofish: false,
                     chaining_sugg: None,
                 };
 
@@ -1436,7 +1436,7 @@ impl<'a> Parser<'a> {
                         {
                             err.suggest_turbofish = Some(op.span.shrink_to_lo());
                         } else {
-                            err.help_turbofish = Some(());
+                            err.help_turbofish = true;
                         }
 
                         let snapshot = self.create_snapshot_for_diagnostic();
@@ -1468,7 +1468,7 @@ impl<'a> Parser<'a> {
                         {
                             err.suggest_turbofish = Some(op.span.shrink_to_lo());
                         } else {
-                            err.help_turbofish = Some(());
+                            err.help_turbofish = true;
                         }
                         // Consume the fn call arguments.
                         match self.consume_fn_args() {
@@ -1487,7 +1487,7 @@ impl<'a> Parser<'a> {
                         {
                             // All we know is that this is `foo < bar >` and *nothing* else. Try to
                             // be helpful, but don't attempt to recover.
-                            err.help_turbofish = Some(());
+                            err.help_turbofish = true;
                         }
 
                         // If it looks like a genuine attempt to chain operators (as opposed to a
@@ -1895,7 +1895,7 @@ impl<'a> Parser<'a> {
         {
             self.dcx().emit_err(ColonAsSemi {
                 span: self.token.span,
-                type_ascription: self.psess.unstable_features.is_nightly_build().then_some(()),
+                type_ascription: self.psess.unstable_features.is_nightly_build(),
             });
             self.bump();
             return true;

compiler/rustc_parse/src/parser/expr.rs

@@ -2162,13 +2162,13 @@ impl<'a> Parser<'a> {
             self.dcx().emit_warn(errors::InvalidLiteralSuffixOnTupleIndex {
                 span,
                 suffix,
-                exception: Some(()),
+                exception: true,
             });
         } else {
             self.dcx().emit_err(errors::InvalidLiteralSuffixOnTupleIndex {
                 span,
                 suffix,
-                exception: None,
+                exception: false,
             });
         }
     }

compiler/rustc_parse/src/parser/item.rs

@@ -1248,8 +1248,8 @@ impl<'a> Parser<'a> {
         let span = self.psess.source_map().guess_head_span(span);
         let descr = kind.descr();
         let help = match kind {
-            ItemKind::DelegationMac(deleg) if deleg.suffixes.is_none() => None,
-            _ => Some(()),
+            ItemKind::DelegationMac(deleg) if deleg.suffixes.is_none() => false,
+            _ => true,
         };
         self.dcx().emit_err(errors::BadItemKind { span, descr, ctx, help });
         None

compiler/rustc_parse/src/parser/pat.rs

@@ -333,7 +333,7 @@ impl<'a> Parser<'a> {
                     span: self.token.span,
                     start: lo,
                     token: self.token.clone(),
-                    note_double_vert: matches!(self.token.kind, token::OrOr).then_some(()),
+                    note_double_vert: matches!(self.token.kind, token::OrOr),
                 });
                 self.bump();
                 true

compiler/rustc_parse/src/parser/path.rs

@@ -261,11 +261,7 @@ impl<'a> Parser<'a> {
                         self.dcx().emit_err(PathSingleColon {
                             span: self.prev_token.span,
                             suggestion: self.prev_token.span.shrink_to_hi(),
-                            type_ascription: self
-                                .psess
-                                .unstable_features
-                                .is_nightly_build()
-                                .then_some(()),
+                            type_ascription: self.psess.unstable_features.is_nightly_build(),
                         });
                     }
                     continue;
@@ -334,11 +330,7 @@ impl<'a> Parser<'a> {
                             err = self.dcx().create_err(PathSingleColon {
                                 span: self.token.span,
                                 suggestion: self.prev_token.span.shrink_to_hi(),
-                                type_ascription: self
-                                    .psess
-                                    .unstable_features
-                                    .is_nightly_build()
-                                    .then_some(()),
+                                type_ascription: self.psess.unstable_features.is_nightly_build(),
                             });
                         }
                         // Attempt to find places where a missing `>` might belong.