Tweak error and move tests

compiler/rustc_parse/src/errors.rs

@@ -2278,9 +2278,8 @@ pub(crate) enum InvalidMutInPattern {
     #[note(parse_note_mut_pattern_usage)]
     NonIdent {
         #[primary_span]
-        #[suggestion(code = "{pat}", applicability = "machine-applicable")]
+        #[suggestion(code = "", applicability = "machine-applicable")]
         span: Span,
-        pat: String,
     },
 }
 

compiler/rustc_parse/src/parser/mod.rs

@@ -830,8 +830,8 @@ impl<'a> Parser<'a> {
                             // https://github.com/rust-lang/rust/issues/72373
                             if self.prev_token.is_ident() && self.token.kind == token::DotDot {
                                 let msg = format!(
-                                    "if you meant to bind the contents of \
-                                    the rest of the array pattern into `{}`, use `@`",
+                                    "if you meant to bind the contents of the rest of the array \
+                                     pattern into `{}`, use `@`",
                                     pprust::token_to_string(&self.prev_token)
                                 );
                                 expect_err

compiler/rustc_parse/src/parser/pat.rs

@@ -638,13 +638,13 @@ impl<'a> Parser<'a> {
 
     /// Error on `mut $pat` where `$pat` is not an ident.
     fn ban_mut_general_pat(&self, lo: Span, pat: &Pat, changed_any_binding: bool) {
-        let span = lo.to(pat.span);
-        let pat = pprust::pat_to_string(&pat);
-
         self.sess.emit_err(if changed_any_binding {
-            InvalidMutInPattern::NestedIdent { span, pat }
+            InvalidMutInPattern::NestedIdent {
+                span: lo.to(pat.span),
+                pat: pprust::pat_to_string(&pat),
+            }
         } else {
-            InvalidMutInPattern::NonIdent { span, pat }
+            InvalidMutInPattern::NonIdent { span: lo.until(pat.span) }
         });
     }
 

tests/ui/parser/issues/issue-32501.stderr

@@ -2,7 +2,7 @@ error: `mut` must be followed by a named binding
   --> $DIR/issue-32501.rs:7:9
    |
 LL |     let mut _ = 0;
-   |         ^^^^^ help: remove the `mut` prefix: `_`
+   |         ^^^^ help: remove the `mut` prefix
    |
    = note: `mut` may be followed by `variable` and `variable @ pattern`
 

tests/ui/parser/issues/issue-65122-mac-invoc-in-mut-patterns.stderr

@@ -2,7 +2,7 @@ error: `mut` must be followed by a named binding
   --> $DIR/issue-65122-mac-invoc-in-mut-patterns.rs:6:13
    |
 LL |         let mut $eval = ();
-   |             ^^^^^^^^^ help: remove the `mut` prefix: `does_not_exist!()`
+   |             ^^^^ help: remove the `mut` prefix
 ...
 LL |     mac1! { does_not_exist!() }
    |     --------------------------- in this macro invocation
@@ -25,7 +25,7 @@ error: `mut` must be followed by a named binding
   --> $DIR/issue-65122-mac-invoc-in-mut-patterns.rs:13:13
    |
 LL |         let mut $eval = ();
-   |             ^^^ help: remove the `mut` prefix: `does_not_exist!()`
+   |             ^^^ help: remove the `mut` prefix
 ...
 LL |     mac2! { does_not_exist!() }
    |     --------------------------- in this macro invocation

tests/ui/parser/mut-patterns.stderr

@@ -2,15 +2,15 @@ error: `mut` must be followed by a named binding
   --> $DIR/mut-patterns.rs:9:9
    |
 LL |     let mut _ = 0;
-   |         ^^^^^ help: remove the `mut` prefix: `_`
+   |         ^^^^ help: remove the `mut` prefix
    |
    = note: `mut` may be followed by `variable` and `variable @ pattern`
 
 error: `mut` must be followed by a named binding
   --> $DIR/mut-patterns.rs:10:9
    |
 LL |     let mut (_, _) = (0, 0);
-   |         ^^^^^^^^^^ help: remove the `mut` prefix: `(_, _)`
+   |         ^^^^ help: remove the `mut` prefix
    |
    = note: `mut` may be followed by `variable` and `variable @ pattern`
 

tests/ui/parser/recover/recover-parens-around-match-arm-head.rs

@@ -0,0 +1,14 @@
+fn main() {
+    let val = 42;
+    let x = match val {
+        (0 if true) => {
+        //~^ ERROR expected identifier, found keyword `if`
+        //~| ERROR expected one of `)`, `,`, `...`, `..=`, `..`, or `|`, found keyword `if`
+        //~| ERROR expected one of `)`, `,`, `@`, or `|`, found keyword `true`
+        //~| ERROR mismatched types
+            42u8
+        }
+        _ => 0u8,
+    };
+    let _y: u32 = x; //~ ERROR mismatched types
+}

tests/ui/parser/recover/recover-parens-around-match-arm-head.stderr

@@ -0,0 +1,49 @@
+error: expected identifier, found keyword `if`
+  --> $DIR/recover-parens-around-match-arm-head.rs:4:12
+   |
+LL |         (0 if true) => {
+   |            ^^ expected identifier, found keyword
+
+error: expected one of `)`, `,`, `...`, `..=`, `..`, or `|`, found keyword `if`
+  --> $DIR/recover-parens-around-match-arm-head.rs:4:12
+   |
+LL |         (0 if true) => {
+   |           -^^ expected one of `)`, `,`, `...`, `..=`, `..`, or `|`
+   |           |
+   |           help: missing `,`
+
+error: expected one of `)`, `,`, `@`, or `|`, found keyword `true`
+  --> $DIR/recover-parens-around-match-arm-head.rs:4:15
+   |
+LL |         (0 if true) => {
+   |              -^^^^ expected one of `)`, `,`, `@`, or `|`
+   |              |
+   |              help: missing `,`
+
+error[E0308]: mismatched types
+  --> $DIR/recover-parens-around-match-arm-head.rs:4:9
+   |
+LL |     let x = match val {
+   |                   --- this expression has type `{integer}`
+LL |         (0 if true) => {
+   |         ^^^^^^^^^^^ expected integer, found `(_, _, _)`
+   |
+   = note: expected type `{integer}`
+             found tuple `(_, _, _)`
+
+error[E0308]: mismatched types
+  --> $DIR/recover-parens-around-match-arm-head.rs:13:19
+   |
+LL |     let _y: u32 = x;
+   |             ---   ^ expected `u32`, found `u8`
+   |             |
+   |             expected due to this
+   |
+help: you can convert a `u8` to a `u32`
+   |
+LL |     let _y: u32 = x.into();
+   |                    +++++++
+
+error: aborting due to 5 previous errors
+
+For more information about this error, try `rustc --explain E0308`.

tests/ui/self/self_type_keyword.stderr

@@ -14,7 +14,7 @@ error: `mut` must be followed by a named binding
   --> $DIR/self_type_keyword.rs:16:9
    |
 LL |         mut Self => (),
-   |         ^^^^^^^^ help: remove the `mut` prefix: `Self`
+   |         ^^^^ help: remove the `mut` prefix
    |
    = note: `mut` may be followed by `variable` and `variable @ pattern`