Recover on misspelled item keyword

compiler/rustc_parse/src/parser/item.rs

@@ -228,8 +228,8 @@ impl<'a> Parser<'a> {
                 body,
                 define_opaque: None,
             }))
-        } else if self.eat_keyword(exp!(Extern)) {
-            if self.eat_keyword(exp!(Crate)) {
+        } else if self.eat_keyword_case(exp!(Extern), case) {
+            if self.eat_keyword_case(exp!(Crate), case) {
                 // EXTERN CRATE
                 self.parse_item_extern_crate()?
             } else {
@@ -247,7 +247,7 @@ impl<'a> Parser<'a> {
             self.bump(); // `static`
             let mutability = self.parse_mutability();
             self.parse_static_item(safety, mutability)?
-        } else if self.check_keyword(exp!(Trait)) || self.check_trait_front_matter() {
+        } else if self.check_keyword_case(exp!(Trait), case) || self.check_trait_front_matter() {
             // TRAIT ITEM
             self.parse_item_trait(attrs, lo)?
         } else if self.check_impl_frontmatter() {
@@ -268,18 +268,18 @@ impl<'a> Parser<'a> {
             }))
         } else if self.is_reuse_path_item() {
             self.parse_item_delegation()?
-        } else if self.check_keyword(exp!(Mod))
-            || self.check_keyword(exp!(Unsafe)) && self.is_keyword_ahead(1, &[kw::Mod])
+        } else if self.check_keyword_case(exp!(Mod), case)
+            || self.check_keyword_case(exp!(Unsafe), case) && self.is_keyword_ahead(1, &[kw::Mod])
         {
             // MODULE ITEM
             self.parse_item_mod(attrs)?
-        } else if self.eat_keyword(exp!(Type)) {
+        } else if self.eat_keyword_case(exp!(Type), case) {
             // TYPE ITEM
             self.parse_type_alias(def_())?
-        } else if self.eat_keyword(exp!(Enum)) {
+        } else if self.eat_keyword_case(exp!(Enum), case) {
             // ENUM ITEM
             self.parse_item_enum()?
-        } else if self.eat_keyword(exp!(Struct)) {
+        } else if self.eat_keyword_case(exp!(Struct), case) {
             // STRUCT ITEM
             self.parse_item_struct()?
         } else if self.is_kw_followed_by_ident(kw::Union) {
@@ -289,7 +289,7 @@ impl<'a> Parser<'a> {
         } else if self.is_builtin() {
             // BUILTIN# ITEM
             return self.parse_item_builtin();
-        } else if self.eat_keyword(exp!(Macro)) {
+        } else if self.eat_keyword_case(exp!(Macro), case) {
             // MACROS 2.0 ITEM
             self.parse_item_decl_macro(lo)?
         } else if let IsMacroRulesItem::Yes { has_bang } = self.is_macro_rules_item() {

tests/ui/parser/misspelled-keywords/assoc-type.rs

@@ -1,6 +1,8 @@
+#![feature(associated_type_defaults)]
+
 trait Animal {
     Type Result = u8;
-    //~^ ERROR expected one of
+    //~^ ERROR keyword `type` is written in the wrong case
 }
 
 fn main() {}

tests/ui/parser/misspelled-keywords/assoc-type.stderr

@@ -1,15 +1,10 @@
-error: expected one of `!` or `::`, found `Result`
-  --> $DIR/assoc-type.rs:2:10
+error: keyword `type` is written in the wrong case
+  --> $DIR/assoc-type.rs:4:5
    |
-LL | trait Animal {
-   |              - while parsing this item list starting here
 LL |     Type Result = u8;
-   |          ^^^^^^ expected one of `!` or `::`
-LL |
-LL | }
-   | - the item list ends here
+   |     ^^^^
    |
-help: write keyword `type` in lowercase
+help: write it in the correct case
    |
 LL -     Type Result = u8;
 LL +     type Result = u8;

tests/ui/parser/misspelled-keywords/struct.rs

@@ -1,4 +1,7 @@
 Struct Foor {
-//~^ ERROR expected one of
+//~^ ERROR keyword `struct` is written in the wrong case
     hello: String,
 }
+
+stuct Barr;
+//~^ ERROR expected one of `!` or `::`, found `Barr`

tests/ui/parser/misspelled-keywords/struct.stderr

@@ -1,14 +1,25 @@
-error: expected one of `!` or `::`, found `Foor`
-  --> $DIR/struct.rs:1:8
+error: keyword `struct` is written in the wrong case
+  --> $DIR/struct.rs:1:1
    |
 LL | Struct Foor {
-   |        ^^^^ expected one of `!` or `::`
+   | ^^^^^^
    |
-help: write keyword `struct` in lowercase (notice the capitalization)
+help: write it in the correct case (notice the capitalization)
    |
 LL - Struct Foor {
 LL + struct Foor {
    |
 
-error: aborting due to 1 previous error
+error: expected one of `!` or `::`, found `Barr`
+  --> $DIR/struct.rs:6:7
+   |
+LL | stuct Barr;
+   |       ^^^^ expected one of `!` or `::`
+   |
+help: there is a keyword `struct` with a similar name
+   |
+LL | struct Barr;
+   |   +
+
+error: aborting due to 2 previous errors