print the appropriate description for the suggestion

Author: m-ysk

compiler/rustc_hir/src/def.rs

@@ -11,7 +11,7 @@ use std::array::IntoIter;
 use std::fmt::Debug;
 
 /// Encodes if a `DefKind::Ctor` is the constructor of an enum variant or a struct.
-#[derive(Clone, Copy, PartialEq, Eq, Encodable, Decodable, Hash, Debug)]
+#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Encodable, Decodable, Hash, Debug)]
 #[derive(HashStable_Generic)]
 pub enum CtorOf {
     /// This `DefKind::Ctor` is a synthesized constructor of a tuple or unit struct.
@@ -21,7 +21,7 @@ pub enum CtorOf {
 }
 
 /// What kind of constructor something is.
-#[derive(Clone, Copy, PartialEq, Eq, Encodable, Decodable, Hash, Debug)]
+#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Encodable, Decodable, Hash, Debug)]
 #[derive(HashStable_Generic)]
 pub enum CtorKind {
     /// Constructor function automatically created by a tuple struct/variant.
@@ -33,7 +33,7 @@ pub enum CtorKind {
 }
 
 /// An attribute that is not a macro; e.g., `#[inline]` or `#[rustfmt::skip]`.
-#[derive(Clone, Copy, PartialEq, Eq, Encodable, Decodable, Hash, Debug)]
+#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Encodable, Decodable, Hash, Debug)]
 #[derive(HashStable_Generic)]
 pub enum NonMacroAttrKind {
     /// Single-segment attribute defined by the language (`#[inline]`)
@@ -50,7 +50,7 @@ pub enum NonMacroAttrKind {
 }
 
 /// What kind of definition something is; e.g., `mod` vs `struct`.
-#[derive(Clone, Copy, PartialEq, Eq, Encodable, Decodable, Hash, Debug)]
+#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Encodable, Decodable, Hash, Debug)]
 #[derive(HashStable_Generic)]
 pub enum DefKind {
     // Type namespace
@@ -297,7 +297,7 @@ impl DefKind {
 /// - the call to `str_to_string` will resolve to [`Res::Def`], with the [`DefId`]
 ///   pointing to the definition of `str_to_string` in the current crate.
 //
-#[derive(Clone, Copy, PartialEq, Eq, Encodable, Decodable, Hash, Debug)]
+#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Encodable, Decodable, Hash, Debug)]
 #[derive(HashStable_Generic)]
 pub enum Res<Id = hir::HirId> {
     /// Definition having a unique ID (`DefId`), corresponds to something defined in user code.

compiler/rustc_hir/src/hir.rs

@@ -2400,7 +2400,7 @@ impl<'hir> Ty<'hir> {
 }
 
 /// Not represented directly in the AST; referred to by name through a `ty_path`.
-#[derive(Copy, Clone, PartialEq, Eq, Encodable, Decodable, Hash, Debug)]
+#[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Encodable, Decodable, Hash, Debug)]
 #[derive(HashStable_Generic)]
 pub enum PrimTy {
     Int(IntTy),

compiler/rustc_resolve/src/diagnostics.rs

@@ -4,7 +4,7 @@ use rustc_ast::ptr::P;
 use rustc_ast::visit::{self, Visitor};
 use rustc_ast::{self as ast, Crate, ItemKind, ModKind, NodeId, Path, CRATE_NODE_ID};
 use rustc_ast_pretty::pprust;
-use rustc_data_structures::fx::FxHashSet;
+use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_errors::struct_span_err;
 use rustc_errors::{Applicability, Diagnostic, DiagnosticBuilder, ErrorGuaranteed, MultiSpan};
 use rustc_feature::BUILTIN_ATTRIBUTES;
@@ -48,13 +48,15 @@ pub(crate) type Suggestion = (Vec<(Span, String)>, String, Applicability);
 /// similarly named label and whether or not it is reachable.
 pub(crate) type LabelSuggestion = (Ident, bool);
 
+#[derive(Clone, PartialEq, Eq)]
 pub(crate) enum SuggestionTarget {
     /// The target has a similar name as the name used by the programmer (probably a typo)
     SimilarlyNamed,
     /// The target is the only valid item that can be used in the corresponding context
     SingleItem,
 }
 
+#[derive(Clone, PartialEq, Eq)]
 pub(crate) struct TypoSuggestion {
     pub candidate: Symbol,
     pub res: Res,
@@ -1829,7 +1831,7 @@ impl<'a> Resolver<'a> {
         &mut self,
         ident: Symbol,
         ribs: Option<&PerNS<Vec<Rib<'a>>>>,
-    ) -> Option<Symbol> {
+    ) -> Option<TypoSuggestion> {
         fn is_type_candidate(res: Res) -> bool {
             matches!(
                 res,
@@ -1884,14 +1886,20 @@ impl<'a> Resolver<'a> {
             }))
         }
 
-        let mut names = names.iter().map(|sugg| sugg.candidate).collect::<Vec<Symbol>>();
-        names.sort();
+        // We sort names here to ensure that the suggestion is deterministic.
+        // (Notice that there may be a pair of TypoSuggestions whose Symbols
+        // are same but Res are different.)
+        names.sort_by_key(|name| (name.candidate, name.res));
         names.dedup();
+        let symbols = names.iter().map(|sugg| sugg.candidate).collect::<Vec<Symbol>>();
+        let typo_suggestions: FxHashMap<Symbol, TypoSuggestion> =
+            names.into_iter().map(|typo_sugg| (typo_sugg.candidate, typo_sugg)).collect();
 
-        match find_best_match_for_name(&names, ident, None) {
+        match find_best_match_for_name(&symbols, ident, None) {
             Some(sugg) if sugg == ident => None,
             sugg => sugg,
         }
+        .map(|sugg| typo_suggestions.get(&sugg).unwrap().clone())
     }
 
     pub(crate) fn report_path_resolution_error(
@@ -2061,8 +2069,12 @@ impl<'a> Resolver<'a> {
             } else {
                 self.find_similarly_named_type(ident.name, ribs).map(|sugg| {
                     (
-                        vec![(ident.span, sugg.to_string())],
-                        String::from("there is a type with a similar name"),
+                        vec![(ident.span, sugg.candidate.to_string())],
+                        format!(
+                            "there is {} {} with a similar name",
+                            sugg.res.article(),
+                            sugg.res.descr(),
+                        ),
                         Applicability::MaybeIncorrect,
                     )
                 })
@@ -2087,8 +2099,12 @@ impl<'a> Resolver<'a> {
             } else {
                 self.find_similarly_named_type(ident.name, ribs).map(|sugg| {
                     (
-                        vec![(ident.span, sugg.to_string())],
-                        String::from("there is a type with a similar name"),
+                        vec![(ident.span, sugg.candidate.to_string())],
+                        format!(
+                            "there is {} {} with a similar name",
+                            sugg.res.article(),
+                            sugg.res.descr()
+                        ),
                         Applicability::MaybeIncorrect,
                     )
                 })

compiler/rustc_span/src/hygiene.rs

@@ -1073,7 +1073,7 @@ impl ExpnKind {
 }
 
 /// The kind of macro invocation or definition.
-#[derive(Clone, Copy, PartialEq, Eq, Encodable, Decodable, Hash, Debug)]
+#[derive(Clone, Copy, PartialEq, Eq, PartialOrd, Ord, Encodable, Decodable, Hash, Debug)]
 #[derive(HashStable_Generic)]
 pub enum MacroKind {
     /// A bang macro `foo!()`.

src/test/ui/generic-associated-types/equality-bound.stderr

@@ -39,7 +39,7 @@ LL | fn sum3<J: Iterator>(i: J) -> i32 where I::Item = i32 {
    |                                         ^
    |                                         |
    |                                         use of undeclared type `I`
-   |                                         help: there is a type with a similar name: `J`
+   |                                         help: there is a type parameter with a similar name: `J`
 
 error: aborting due to 4 previous errors
 

src/test/ui/macros/builtin-prelude-no-accidents.stderr

@@ -17,7 +17,7 @@ LL |     type B = vec::Vec<u8>;
    |              ^^^
    |              |
    |              use of undeclared crate or module `vec`
-   |              help: there is a type with a similar name (notice the capitalization): `Vec`
+   |              help: there is a struct with a similar name (notice the capitalization): `Vec`
 
 error: aborting due to 3 previous errors
 

src/test/ui/macros/macro_path_as_generic_bound.stderr

@@ -5,7 +5,7 @@ LL | foo!(m::m2::A);
    |      ^
    |      |
    |      use of undeclared crate or module `m`
-   |      help: there is a type with a similar name: `T`
+   |      help: there is a type parameter with a similar name: `T`
 
 error: aborting due to previous error
 

src/test/ui/pattern/pattern-error-continue.stderr

@@ -5,7 +5,7 @@ LL |         E::V => {}
    |         ^
    |         |
    |         use of undeclared type `E`
-   |         help: there is a type with a similar name: `Eq`
+   |         help: there is a trait with a similar name: `Eq`
 
 error[E0532]: expected tuple struct or tuple variant, found unit variant `A::D`
   --> $DIR/pattern-error-continue.rs:18:9

src/test/ui/resolve/suggest-similar-type-name.stderr

@@ -5,7 +5,7 @@ LL |     FooTyp::bar()
    |     ^^^^^^
    |     |
    |     use of undeclared type `FooTyp`
-   |     help: there is a type with a similar name: `FooType`
+   |     help: there is a struct with a similar name: `FooType`
 
 error: aborting due to previous error
 

src/test/ui/resolve/suggest-type-to-lowercase-path.stderr

@@ -5,7 +5,7 @@ LL |     let _ = string::new();
    |             ^^^^^^
    |             |
    |             use of undeclared crate or module `string`
-   |             help: there is a type with a similar name (notice the capitalization): `String`
+   |             help: there is a struct with a similar name (notice the capitalization): `String`
 
 error: aborting due to previous error
 

src/test/ui/suggestions/type-ascription-instead-of-path.stderr

@@ -5,7 +5,7 @@ LL |     std:io::stdin();
    |         ^^
    |         |
    |         use of undeclared crate or module `io`
-   |         help: there is a type with a similar name: `i8`
+   |         help: there is a builtin type with a similar name: `i8`
 
 error[E0423]: expected value, found crate `std`
   --> $DIR/type-ascription-instead-of-path.rs:2:5