Rollup merge of #132332 - nnethercote:use-token_descr-more, r=estebank

Use `token_descr` more in error messages

This is the first two commits from #124141, put into their own PR to get things rolling. Commit messages have the details.

r? ``@estebank``
cc ``@petrochenkov``

Author: matthiaskrgr

compiler/rustc_expand/messages.ftl

@@ -74,7 +74,7 @@ expand_helper_attribute_name_invalid =
     `{$name}` cannot be a name of derive helper attribute
 
 expand_incomplete_parse =
-    macro expansion ignores token `{$token}` and any following
+    macro expansion ignores {$descr} and any tokens following
     .label = caused by the macro expansion here
     .note = the usage of `{$macro_path}!` is likely invalid in {$kind_name} context
     .suggestion_add_semi = you might be missing a semicolon here

compiler/rustc_expand/src/errors.rs

@@ -275,7 +275,7 @@ pub(crate) struct UnsupportedKeyValue {
 pub(crate) struct IncompleteParse<'a> {
     #[primary_span]
     pub span: Span,
-    pub token: Cow<'a, str>,
+    pub descr: String,
     #[label]
     pub label_span: Span,
     pub macro_path: &'a ast::Path,

compiler/rustc_expand/src/expand.rs

@@ -21,6 +21,7 @@ use rustc_errors::PResult;
 use rustc_feature::Features;
 use rustc_parse::parser::{
     AttemptLocalParseRecovery, CommaRecoveryMode, ForceCollect, Parser, RecoverColon, RecoverComma,
+    token_descr,
 };
 use rustc_parse::validate_attr;
 use rustc_session::lint::BuiltinLintDiag;
@@ -1013,7 +1014,7 @@ pub(crate) fn ensure_complete_parse<'a>(
     span: Span,
 ) {
     if parser.token != token::Eof {
-        let token = pprust::token_to_string(&parser.token);
+        let descr = token_descr(&parser.token);
         // Avoid emitting backtrace info twice.
         let def_site_span = parser.token.span.with_ctxt(SyntaxContext::root());
 
@@ -1029,7 +1030,7 @@ pub(crate) fn ensure_complete_parse<'a>(
 
         parser.dcx().emit_err(IncompleteParse {
             span: def_site_span,
-            token,
+            descr,
             label_span: span,
             macro_path,
             kind_name,

compiler/rustc_expand/src/mbe/diagnostics.rs

@@ -2,10 +2,9 @@ use std::borrow::Cow;
 
 use rustc_ast::token::{self, Token, TokenKind};
 use rustc_ast::tokenstream::TokenStream;
-use rustc_ast_pretty::pprust;
 use rustc_errors::{Applicability, Diag, DiagCtxtHandle, DiagMessage};
 use rustc_macros::Subdiagnostic;
-use rustc_parse::parser::{Parser, Recovery};
+use rustc_parse::parser::{Parser, Recovery, token_descr};
 use rustc_session::parse::ParseSess;
 use rustc_span::source_map::SourceMap;
 use rustc_span::symbol::Ident;
@@ -336,17 +335,11 @@ pub(super) fn annotate_doc_comment(err: &mut Diag<'_>, sm: &SourceMap, span: Spa
 /// other tokens, this is "unexpected token...".
 pub(super) fn parse_failure_msg(tok: &Token, expected_token: Option<&Token>) -> Cow<'static, str> {
     if let Some(expected_token) = expected_token {
-        Cow::from(format!(
-            "expected `{}`, found `{}`",
-            pprust::token_to_string(expected_token),
-            pprust::token_to_string(tok),
-        ))
+        Cow::from(format!("expected {}, found {}", token_descr(expected_token), token_descr(tok)))
     } else {
         match tok.kind {
             token::Eof => Cow::from("unexpected end of macro invocation"),
-            _ => {
-                Cow::from(format!("no rules expected the token `{}`", pprust::token_to_string(tok)))
-            }
+            _ => Cow::from(format!("no rules expected {}", token_descr(tok))),
         }
     }
 }

compiler/rustc_expand/src/mbe/macro_parser.rs

@@ -78,11 +78,10 @@ use std::rc::Rc;
 pub(crate) use NamedMatch::*;
 pub(crate) use ParseResult::*;
 use rustc_ast::token::{self, DocComment, NonterminalKind, Token};
-use rustc_ast_pretty::pprust;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_errors::ErrorGuaranteed;
 use rustc_lint_defs::pluralize;
-use rustc_parse::parser::{ParseNtResult, Parser};
+use rustc_parse::parser::{ParseNtResult, Parser, token_descr};
 use rustc_span::Span;
 use rustc_span::symbol::{Ident, MacroRulesNormalizedIdent};
 
@@ -150,7 +149,7 @@ impl Display for MatcherLoc {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         match self {
             MatcherLoc::Token { token } | MatcherLoc::SequenceSep { separator: token } => {
-                write!(f, "`{}`", pprust::token_to_string(token))
+                write!(f, "{}", token_descr(token))
             }
             MatcherLoc::MetaVarDecl { bind, kind, .. } => {
                 write!(f, "meta-variable `${bind}")?;

compiler/rustc_parse/src/parser/mod.rs

@@ -424,7 +424,7 @@ impl TokenDescription {
     }
 }
 
-pub(super) fn token_descr(token: &Token) -> String {
+pub fn token_descr(token: &Token) -> String {
     let name = pprust::token_to_string(token).to_string();
 
     let kind = match (TokenDescription::from_token(token), &token.kind) {

tests/ui/array-slice-vec/vec-macro-with-comma-only.rs

@@ -1,3 +1,3 @@
 pub fn main() {
-    vec![,]; //~ ERROR no rules expected the token `,`
+    vec![,]; //~ ERROR no rules expected `,`
 }

tests/ui/array-slice-vec/vec-macro-with-comma-only.stderr

@@ -1,4 +1,4 @@
-error: no rules expected the token `,`
+error: no rules expected `,`
   --> $DIR/vec-macro-with-comma-only.rs:2:10
    |
 LL |     vec![,];

tests/ui/editions/edition-keywords-2015-2015-parsing.rs

@@ -13,8 +13,8 @@ pub fn check_async() {
     let mut r#async = 1; // OK
 
     r#async = consumes_async!(async); // OK
-    r#async = consumes_async!(r#async); //~ ERROR no rules expected the token `r#async`
-    r#async = consumes_async_raw!(async); //~ ERROR no rules expected the token `async`
+    r#async = consumes_async!(r#async); //~ ERROR no rules expected `r#async`
+    r#async = consumes_async_raw!(async); //~ ERROR no rules expected `async`
     r#async = consumes_async_raw!(r#async); // OK
 
     if passes_ident!(async) == 1 {} // OK

tests/ui/editions/edition-keywords-2015-2015-parsing.stderr

@@ -1,4 +1,4 @@
-error: no rules expected the token `r#async`
+error: no rules expected `r#async`
   --> $DIR/edition-keywords-2015-2015-parsing.rs:16:31
    |
 LL |     r#async = consumes_async!(r#async);
@@ -10,7 +10,7 @@ note: while trying to match `async`
 LL |     (async) => (1)
    |      ^^^^^
 
-error: no rules expected the token `async`
+error: no rules expected `async`
   --> $DIR/edition-keywords-2015-2015-parsing.rs:17:35
    |
 LL |     r#async = consumes_async_raw!(async);