Add AcceptContext::suggestions

Signed-off-by: Jonathan Brouwer <jonathantbrouwer@gmail.com>

Author: JonathanBrouwer

compiler/rustc_attr_parsing/src/attributes/cfg.rs

@@ -326,7 +326,8 @@ pub fn parse_cfg_attr(
  }) {
  Ok(r) => return Some(r),
  Err(e) => {
- let suggestions = CFG_ATTR_TEMPLATE.suggestions(cfg_attr.style, sym::cfg_attr);
+ let suggestions =
+ CFG_ATTR_TEMPLATE.suggestions(Some(cfg_attr.style), sym::cfg_attr);
  e.with_span_suggestions(
  cfg_attr.span,
  "must be of the form",
@@ -356,7 +357,7 @@ pub fn parse_cfg_attr(
  template: CFG_ATTR_TEMPLATE,
  attribute: AttrPath::from_ast(&cfg_attr.get_normal_item().path),
  reason,
- attr_style: cfg_attr.style,
+ suggestions: CFG_ATTR_TEMPLATE.suggestions(Some(cfg_attr.style), sym::cfg_attr),
  });
  }
  }

compiler/rustc_attr_parsing/src/attributes/inline.rs

@@ -56,8 +56,7 @@ impl<S: Stage> SingleAttributeParser<S> for InlineParser {
  }
  }
  ArgParser::NameValue(_) => {
- let suggestions = <Self as SingleAttributeParser<S>>::TEMPLATE
- .suggestions(cx.attr_style, "inline");
+ let suggestions = cx.suggestions();
  let span = cx.attr_span;
  cx.emit_lint(AttributeLintKind::IllFormedAttributeInput { suggestions }, span);
  return None;

compiler/rustc_attr_parsing/src/attributes/link_attrs.rs

@@ -71,8 +71,7 @@ impl<S: Stage> CombineAttributeParser<S> for LinkParser {
  // Specifically `#[link = "dl"]` is accepted with a FCW
  // For more information, see https://github.com/rust-lang/rust/pull/143193
  ArgParser::NameValue(nv) if nv.value_as_str().is_some_and(|v| v == sym::dl) => {
- let suggestions = <Self as CombineAttributeParser<S>>::TEMPLATE
- .suggestions(cx.attr_style, "link");
+ let suggestions = cx.suggestions();
  let span = cx.attr_span;
  cx.emit_lint(AttributeLintKind::IllFormedAttributeInput { suggestions }, span);
  return None;

compiler/rustc_attr_parsing/src/attributes/macro_attrs.rs

@@ -1,4 +1,3 @@
-use rustc_ast::AttrStyle;
 use rustc_errors::DiagArgValue;
 use rustc_hir::attrs::MacroUseArgs;
 
@@ -102,7 +101,7 @@ impl<S: Stage> AttributeParser<S> for MacroUseParser {
  }
  }
  ArgParser::NameValue(_) => {
- let suggestions = MACRO_USE_TEMPLATE.suggestions(cx.attr_style, sym::macro_use);
+ let suggestions = cx.suggestions();
  cx.emit_err(IllFormedAttributeInputLint {
  num_suggestions: suggestions.len(),
  suggestions: DiagArgValue::StrListSepByAnd(
@@ -149,19 +148,14 @@ impl<S: Stage> SingleAttributeParser<S> for MacroExportParser {
  ]);
 
  fn convert(cx: &mut AcceptContext<'_, '_, S>, args: &ArgParser<'_>) -> Option<AttributeKind> {
- let suggestions = || {
- <Self as SingleAttributeParser<S>>::TEMPLATE
- .suggestions(AttrStyle::Inner, "macro_export")
- };
  let local_inner_macros = match args {
  ArgParser::NoArgs => false,
  ArgParser::List(list) => {
  let Some(l) = list.single() else {
  let span = cx.attr_span;
+ let suggestions = cx.suggestions();
  cx.emit_lint(
- AttributeLintKind::InvalidMacroExportArguments {
- suggestions: suggestions(),
- },
+ AttributeLintKind::InvalidMacroExportArguments { suggestions },
  span,
  );
  return None;
@@ -170,10 +164,9 @@ impl<S: Stage> SingleAttributeParser<S> for MacroExportParser {
  Some(sym::local_inner_macros) => true,
  _ => {
  let span = cx.attr_span;
+ let suggestions = cx.suggestions();
  cx.emit_lint(
- AttributeLintKind::InvalidMacroExportArguments {
- suggestions: suggestions(),
- },
+ AttributeLintKind::InvalidMacroExportArguments { suggestions },
  span,
  );
  return None;
@@ -182,7 +175,7 @@ impl<S: Stage> SingleAttributeParser<S> for MacroExportParser {
  }
  ArgParser::NameValue(_) => {
  let span = cx.attr_span;
- let suggestions = suggestions();
+ let suggestions = cx.suggestions();
  cx.emit_err(IllFormedAttributeInputLint {
  num_suggestions: suggestions.len(),
  suggestions: DiagArgValue::StrListSepByAnd(

compiler/rustc_attr_parsing/src/attributes/must_use.rs

@@ -45,8 +45,7 @@ impl<S: Stage> SingleAttributeParser<S> for MustUseParser {
  Some(value_str)
  }
  ArgParser::List(_) => {
- let suggestions = <Self as SingleAttributeParser<S>>::TEMPLATE
- .suggestions(cx.attr_style, "must_use");
+ let suggestions = cx.suggestions();
  cx.emit_err(IllFormedAttributeInputLint {
  num_suggestions: suggestions.len(),
  suggestions: DiagArgValue::StrListSepByAnd(

compiler/rustc_attr_parsing/src/attributes/test_attrs.rs

@@ -20,8 +20,7 @@ impl<S: Stage> SingleAttributeParser<S> for IgnoreParser {
  ArgParser::NoArgs => None,
  ArgParser::NameValue(name_value) => {
  let Some(str_value) = name_value.value_as_str() else {
- let suggestions = <Self as SingleAttributeParser<S>>::TEMPLATE
- .suggestions(cx.attr_style, "ignore");
+ let suggestions = cx.suggestions();
  let span = cx.attr_span;
  cx.emit_lint(
  AttributeLintKind::IllFormedAttributeInput { suggestions },
@@ -32,8 +31,7 @@ impl<S: Stage> SingleAttributeParser<S> for IgnoreParser {
  Some(str_value)
  }
  ArgParser::List(_) => {
- let suggestions = <Self as SingleAttributeParser<S>>::TEMPLATE
- .suggestions(cx.attr_style, "ignore");
+ let suggestions = cx.suggestions();
  let span = cx.attr_span;
  cx.emit_lint(AttributeLintKind::IllFormedAttributeInput { suggestions }, span);
  return None;

compiler/rustc_attr_parsing/src/context.rs

@@ -427,7 +427,7 @@ impl<'f, 'sess: 'f, S: Stage> AcceptContext<'f, 'sess, S> {
  i.kind.is_bytestr().then(|| self.sess().source_map().start_point(i.span))
  }),
  },
- attr_style: self.attr_style,
+ suggestions: self.suggestions(),
  })
  }
 
@@ -438,7 +438,7 @@ impl<'f, 'sess: 'f, S: Stage> AcceptContext<'f, 'sess, S> {
  template: self.template.clone(),
  attribute: self.attr_path.clone(),
  reason: AttributeParseErrorReason::ExpectedIntegerLiteral,
- attr_style: self.attr_style,
+ suggestions: self.suggestions(),
  })
  }
 
@@ -449,7 +449,7 @@ impl<'f, 'sess: 'f, S: Stage> AcceptContext<'f, 'sess, S> {
  template: self.template.clone(),
  attribute: self.attr_path.clone(),
  reason: AttributeParseErrorReason::ExpectedList,
- attr_style: self.attr_style,
+ suggestions: self.suggestions(),
  })
  }
 
@@ -460,7 +460,7 @@ impl<'f, 'sess: 'f, S: Stage> AcceptContext<'f, 'sess, S> {
  template: self.template.clone(),
  attribute: self.attr_path.clone(),
  reason: AttributeParseErrorReason::ExpectedNoArgs,
- attr_style: self.attr_style,
+ suggestions: self.suggestions(),
  })
  }
 
@@ -472,7 +472,7 @@ impl<'f, 'sess: 'f, S: Stage> AcceptContext<'f, 'sess, S> {
  template: self.template.clone(),
  attribute: self.attr_path.clone(),
  reason: AttributeParseErrorReason::ExpectedIdentifier,
- attr_style: self.attr_style,
+ suggestions: self.suggestions(),
  })
  }
 
@@ -485,7 +485,7 @@ impl<'f, 'sess: 'f, S: Stage> AcceptContext<'f, 'sess, S> {
  template: self.template.clone(),
  attribute: self.attr_path.clone(),
  reason: AttributeParseErrorReason::ExpectedNameValue(name),
- attr_style: self.attr_style,
+ suggestions: self.suggestions(),
  })
  }
 
@@ -497,7 +497,7 @@ impl<'f, 'sess: 'f, S: Stage> AcceptContext<'f, 'sess, S> {
  template: self.template.clone(),
  attribute: self.attr_path.clone(),
  reason: AttributeParseErrorReason::DuplicateKey(key),
- attr_style: self.attr_style,
+ suggestions: self.suggestions(),
  })
  }
 
@@ -510,7 +510,7 @@ impl<'f, 'sess: 'f, S: Stage> AcceptContext<'f, 'sess, S> {
  template: self.template.clone(),
  attribute: self.attr_path.clone(),
  reason: AttributeParseErrorReason::UnexpectedLiteral,
- attr_style: self.attr_style,
+ suggestions: self.suggestions(),
  })
  }
 
@@ -521,7 +521,7 @@ impl<'f, 'sess: 'f, S: Stage> AcceptContext<'f, 'sess, S> {
  template: self.template.clone(),
  attribute: self.attr_path.clone(),
  reason: AttributeParseErrorReason::ExpectedSingleArgument,
- attr_style: self.attr_style,
+ suggestions: self.suggestions(),
  })
  }
 
@@ -532,7 +532,7 @@ impl<'f, 'sess: 'f, S: Stage> AcceptContext<'f, 'sess, S> {
  template: self.template.clone(),
  attribute: self.attr_path.clone(),
  reason: AttributeParseErrorReason::ExpectedAtLeastOneArgument,
- attr_style: self.attr_style,
+ suggestions: self.suggestions(),
  })
  }
 
@@ -552,7 +552,7 @@ impl<'f, 'sess: 'f, S: Stage> AcceptContext<'f, 'sess, S> {
  strings: false,
  list: false,
  },
- attr_style: self.attr_style,
+ suggestions: self.suggestions(),
  })
  }
 
@@ -573,7 +573,7 @@ impl<'f, 'sess: 'f, S: Stage> AcceptContext<'f, 'sess, S> {
  strings: false,
  list: true,
  },
- attr_style: self.attr_style,
+ suggestions: self.suggestions(),
  })
  }
 
@@ -593,7 +593,7 @@ impl<'f, 'sess: 'f, S: Stage> AcceptContext<'f, 'sess, S> {
  strings: true,
  list: false,
  },
- attr_style: self.attr_style,
+ suggestions: self.suggestions(),
  })
  }
 
@@ -605,6 +605,10 @@ impl<'f, 'sess: 'f, S: Stage> AcceptContext<'f, 'sess, S> {
  span,
  );
  }
+
+ pub(crate) fn suggestions(&self) -> Vec<String> {
+ self.template.suggestions(Some(self.attr_style), &self.attr_path)
+ }
 }
 
 impl<'f, 'sess, S: Stage> Deref for AcceptContext<'f, 'sess, S> {

compiler/rustc_attr_parsing/src/session_diagnostics.rs

@@ -1,6 +1,6 @@
 use std::num::IntErrorKind;
 
-use rustc_ast::{self as ast, AttrStyle, Path};
+use rustc_ast::{self as ast, Path};
 use rustc_errors::codes::*;
 use rustc_errors::{
  Applicability, Diag, DiagArgValue, DiagCtxtHandle, Diagnostic, EmissionGuarantee, Level,
@@ -613,10 +613,10 @@ pub(crate) enum AttributeParseErrorReason<'a> {
 pub(crate) struct AttributeParseError<'a> {
  pub(crate) span: Span,
  pub(crate) attr_span: Span,
- pub(crate) attr_style: AttrStyle,
  pub(crate) template: AttributeTemplate,
  pub(crate) attribute: AttrPath,
  pub(crate) reason: AttributeParseErrorReason<'a>,
+ pub(crate) suggestions: Vec<String>,
 }
 
 impl<'a, G: EmissionGuarantee> Diagnostic<'a, G> for AttributeParseError<'_> {
@@ -752,16 +752,15 @@ impl<'a, G: EmissionGuarantee> Diagnostic<'a, G> for AttributeParseError<'_> {
  if let Some(link) = self.template.docs {
  diag.note(format!("for more information, visit <{link}>"));
  }
- let suggestions = self.template.suggestions(self.attr_style, &name);
 
  diag.span_suggestions(
  self.attr_span,
- if suggestions.len() == 1 {
+ if self.suggestions.len() == 1 {
  "must be of the form"
  } else {
  "try changing it to one of the following valid forms of the attribute"
  },
- suggestions,
+ self.suggestions,
  Applicability::HasPlaceholders,
  );
 

compiler/rustc_feature/src/builtin_attrs.rs

@@ -133,24 +133,29 @@ pub struct AttributeTemplate {
 }
 
 impl AttributeTemplate {
- pub fn suggestions(&self, style: AttrStyle, name: impl std::fmt::Display) -> Vec<String> {
+ pub fn suggestions(
+ &self,
+ style: Option<AttrStyle>,
+ name: impl std::fmt::Display,
+ ) -> Vec<String> {
  let mut suggestions = vec![];
- let inner = match style {
- AttrStyle::Outer => "",
- AttrStyle::Inner => "!",
+ let (start, end) = match style {
+ Some(AttrStyle::Outer) => ("#[", "]"),
+ Some(AttrStyle::Inner) => ("#![", "]"),
+ None => ("", ""),
  };
  if self.word {
- suggestions.push(format!("#{inner}[{name}]"));
+ suggestions.push(format!("{start}{name}{end}"));
  }
  if let Some(descr) = self.list {
  for descr in descr {
- suggestions.push(format!("#{inner}[{name}({descr})]"));
+ suggestions.push(format!("{start}{name}({descr}){end}"));
  }
  }
- suggestions.extend(self.one_of.iter().map(|&word| format!("#{inner}[{name}({word})]")));
+ suggestions.extend(self.one_of.iter().map(|&word| format!("{start}{name}({word}){end}")));
  if let Some(descr) = self.name_value_str {
  for descr in descr {
- suggestions.push(format!("#{inner}[{name} = \"{descr}\"]"));
+ suggestions.push(format!("{start}{name} = \"{descr}\"{end}"));
  }
  }
  suggestions.sort();

tests/ui/attributes/invalid_macro_export_argument.allow.stderr

@@ -1,5 +1,5 @@
 Future incompatibility report: Future breakage diagnostic:
-warning: valid forms for the attribute are `#![macro_export(local_inner_macros)]` and `#![macro_export]`
+warning: valid forms for the attribute are `#[macro_export(local_inner_macros)]` and `#[macro_export]`
  --> $DIR/invalid_macro_export_argument.rs:7:1
  |
 LL | #[macro_export(hello, world)]
@@ -9,7 +9,7 @@ LL | #[macro_export(hello, world)]
  = note: for more information, see issue #57571 <https://github.com/rust-lang/rust/issues/57571>
 
 Future breakage diagnostic:
-warning: valid forms for the attribute are `#![macro_export(local_inner_macros)]` and `#![macro_export]`
+warning: valid forms for the attribute are `#[macro_export(local_inner_macros)]` and `#[macro_export]`
  --> $DIR/invalid_macro_export_argument.rs:14:1
  |
 LL | #[macro_export(not_local_inner_macros)]
@@ -19,7 +19,7 @@ LL | #[macro_export(not_local_inner_macros)]
  = note: for more information, see issue #57571 <https://github.com/rust-lang/rust/issues/57571>
 
 Future breakage diagnostic:
-warning: valid forms for the attribute are `#![macro_export(local_inner_macros)]` and `#![macro_export]`
+warning: valid forms for the attribute are `#[macro_export(local_inner_macros)]` and `#[macro_export]`
  --> $DIR/invalid_macro_export_argument.rs:31:1
  |
 LL | #[macro_export()]
@@ -29,7 +29,7 @@ LL | #[macro_export()]
  = note: for more information, see issue #57571 <https://github.com/rust-lang/rust/issues/57571>
 
 Future breakage diagnostic:
-warning: valid forms for the attribute are `#![macro_export(local_inner_macros)]` and `#![macro_export]`
+warning: valid forms for the attribute are `#[macro_export(local_inner_macros)]` and `#[macro_export]`
  --> $DIR/invalid_macro_export_argument.rs:38:1
  |
 LL | #[macro_export("blah")]