soften the wording for removing type ascription

Author: chenyukang

compiler/rustc_builtin_macros/src/asm.rs

@@ -68,8 +68,7 @@ pub fn parse_asm_args<'a>(
         if !p.eat(&token::Comma) {
             if allow_templates {
                 // After a template string, we always expect *only* a comma...
-                let mut err = diag.create_err(errors::AsmExpectedComma { span: p.token.span });
-                return Err(err);
+                return Err(diag.create_err(errors::AsmExpectedComma { span: p.token.span }));
             } else {
                 // ...after that delegate to `expect` to also include the other expected tokens.
                 return Err(p.expect(&token::Comma).err().unwrap());

compiler/rustc_parse/messages.ftl

@@ -426,7 +426,8 @@ parse_path_single_colon = path separator must be a double colon
 parse_colon_as_semi = statements are terminated with a semicolon
     .suggestion = use a semicolon instead
 
-parse_type_ascription_removed = type ascription syntax has been removed, see issue #101728 <https://github.com/rust-lang/rust/issues/101728>
+parse_type_ascription_removed =
+    if you meant to annotate an expression with a type, the type ascription syntax has been removed, see issue #101728 <https://github.com/rust-lang/rust/issues/101728>
 
 parse_where_clause_before_tuple_struct_body = where clauses are not allowed before tuple struct bodies
     .label = unexpected where clause

compiler/rustc_parse/src/parser/diagnostics.rs

@@ -1569,14 +1569,9 @@ impl<'a> Parser<'a> {
     }
 
     pub(super) fn expect_semi(&mut self) -> PResult<'a, ()> {
-        if self.eat(&token::Semi) {
+        if self.eat(&token::Semi) || self.recover_colon_as_semi() {
             return Ok(());
         }
-
-        if self.recover_colon_as_semi() {
-            return Ok(());
-        }
-
         self.expect(&token::Semi).map(drop) // Error unconditionally
     }
 
@@ -1597,9 +1592,7 @@ impl<'a> Parser<'a> {
                 span: self.token.span,
                 type_ascription: self.sess.unstable_features.is_nightly_build().then_some(()),
             });
-
             self.bump();
-
             return true;
         }
 

compiler/rustc_parse/src/parser/path.rs

@@ -9,7 +9,7 @@ use rustc_ast::{
     AssocConstraintKind, BlockCheckMode, GenericArg, GenericArgs, Generics, ParenthesizedArgs,
     Path, PathSegment, QSelf,
 };
-use rustc_errors::{pluralize, Applicability, IntoDiagnostic, PResult};
+use rustc_errors::{Applicability, IntoDiagnostic, PResult};
 use rustc_span::source_map::{BytePos, Span};
 use rustc_span::symbol::{kw, sym, Ident};
 use std::mem;

compiler/rustc_parse/src/parser/stmt.rs

@@ -645,7 +645,7 @@ impl<'a> Parser<'a> {
 
                             if self.recover_colon_as_semi() {
                                 // recover_colon_as_semi has already emitted a nicer error.
-                                e.cancel();
+                                e.delay_as_bug();
                                 add_semi_to_stmt = true;
                                 eat_semi = false;
 
@@ -672,7 +672,7 @@ impl<'a> Parser<'a> {
                                         };
                                         match self.parse_expr_labeled(label, false) {
                                             Ok(labeled_expr) => {
-                                                e.cancel();
+                                                e.delay_as_bug();
                                                 self.sess.emit_err(MalformedLoopLabel {
                                                     span: label.ident.span,
                                                     correct_label: label.ident,

tests/ui/generics/single-colon-path-not-const-generics.stderr

@@ -6,7 +6,7 @@ LL | pub struct Foo {
 LL |   a: Vec<foo::bar:A>,
    |                  ^ help: use a double colon instead: `::`
    |
-   = note: type ascription syntax has been removed, see issue #101728 <https://github.com/rust-lang/rust/issues/101728>
+   = note: if you meant to annotate an expression with a type, the type ascription syntax has been removed, see issue #101728 <https://github.com/rust-lang/rust/issues/101728>
 
 error: aborting due to previous error
 

tests/ui/suggestions/type-ascription-instead-of-method.stderr

@@ -4,7 +4,7 @@ error: path separator must be a double colon
 LL |     let _ = Box:new("foo".to_string());
    |                ^ help: use a double colon instead: `::`
    |
-   = note: type ascription syntax has been removed, see issue #101728 <https://github.com/rust-lang/rust/issues/101728>
+   = note: if you meant to annotate an expression with a type, the type ascription syntax has been removed, see issue #101728 <https://github.com/rust-lang/rust/issues/101728>
 
 error: aborting due to previous error
 

tests/ui/suggestions/type-ascription-instead-of-path.stderr

@@ -4,7 +4,7 @@ error: path separator must be a double colon
 LL |     std:io::stdin();
    |        ^ help: use a double colon instead: `::`
    |
-   = note: type ascription syntax has been removed, see issue #101728 <https://github.com/rust-lang/rust/issues/101728>
+   = note: if you meant to annotate an expression with a type, the type ascription syntax has been removed, see issue #101728 <https://github.com/rust-lang/rust/issues/101728>
 
 error: aborting due to previous error
 

tests/ui/suggestions/type-ascription-instead-of-variant.stderr

@@ -4,7 +4,7 @@ error: path separator must be a double colon
 LL |     let _ = Option:Some("");
    |                   ^ help: use a double colon instead: `::`
    |
-   = note: type ascription syntax has been removed, see issue #101728 <https://github.com/rust-lang/rust/issues/101728>
+   = note: if you meant to annotate an expression with a type, the type ascription syntax has been removed, see issue #101728 <https://github.com/rust-lang/rust/issues/101728>
 
 error: aborting due to previous error
 

tests/ui/type/ascription/issue-47666.stderr

@@ -4,7 +4,7 @@ error: path separator must be a double colon
 LL |     let _ = Option:Some(vec![0, 1]);
    |                   ^ help: use a double colon instead: `::`
    |
-   = note: type ascription syntax has been removed, see issue #101728 <https://github.com/rust-lang/rust/issues/101728>
+   = note: if you meant to annotate an expression with a type, the type ascription syntax has been removed, see issue #101728 <https://github.com/rust-lang/rust/issues/101728>
 
 error: aborting due to previous error