Bubble parse error when expecting )

Author: estebank

compiler/rustc_parse/src/parser/mod.rs

@@ -873,6 +873,9 @@ impl<'a> Parser<'a> {
                                     if self.token == token::Colon {
                                         // we will try to recover in `maybe_recover_struct_lit_bad_delims`
                                         return Err(expect_err);
+                                    } else if let [token::CloseDelim(Delimiter::Parenthesis)] = kets
+                                    {
+                                        return Err(expect_err);
                                     } else {
                                         expect_err.emit();
                                         break;

tests/ui/lint/issue-103435-extra-parentheses.fixed

@@ -12,7 +12,7 @@ fn main() {
     //~^ ERROR unnecessary parentheses around `if` condition
 
     // reported by parser
-    for _x in 1..10 {}
+    for(_x in 1..10){}
     //~^ ERROR expected one of
     //~| ERROR unexpected parentheses surrounding
 }

tests/ui/lint/issue-103435-extra-parentheses.stderr

@@ -4,18 +4,6 @@ error: expected one of `)`, `,`, `@`, or `|`, found keyword `in`
 LL |     for(_x in 1..10){}
    |            ^^ expected one of `)`, `,`, `@`, or `|`
 
-error: unexpected parentheses surrounding `for` loop head
-  --> $DIR/issue-103435-extra-parentheses.rs:15:8
-   |
-LL |     for(_x in 1..10){}
-   |        ^           ^
-   |
-help: remove parentheses in `for` loop
-   |
-LL -     for(_x in 1..10){}
-LL +     for _x in 1..10 {}
-   |
-
 error: unnecessary parentheses around pattern
   --> $DIR/issue-103435-extra-parentheses.rs:5:11
    |
@@ -57,5 +45,5 @@ LL -     if(2 == 1){}
 LL +     if 2 == 1 {}
    |
 
-error: aborting due to 5 previous errors
+error: aborting due to 4 previous errors
 

tests/ui/parser/issues/issue-68890.stderr

@@ -8,15 +8,11 @@ error: expected one of `)`, `+`, or `,`, found `a`
   --> $DIR/issue-68890.rs:1:15
    |
 LL | enum e{A((?'a a+?+l))}
-   |               ^ expected one of `)`, `+`, or `,`
-
-error: expected item, found `)`
-  --> $DIR/issue-68890.rs:1:21
-   |
-LL | enum e{A((?'a a+?+l))}
-   |                     ^ expected item
+   |      -        ^ expected one of `)`, `+`, or `,`
+   |      |
+   |      while parsing this enum
    |
-   = note: for a full list of items that can appear in modules, see <https://doc.rust-lang.org/reference/items.html>
+   = help: enum variants can be `Variant`, `Variant = <integer>`, `Variant(Type, ..., TypeN)` or `Variant { fields: Types }`
 
-error: aborting due to 3 previous errors
+error: aborting due to 2 previous errors
 

tests/ui/parser/recover/recover-enum2.stderr

@@ -9,8 +9,20 @@ LL |             abc: {},
 error: expected one of `!`, `(`, `)`, `+`, `,`, `::`, or `<`, found `{`
   --> $DIR/recover-enum2.rs:25:22
    |
+LL |         enum Test4 {
+   |              ----- while parsing this enum
 LL |             Nope(i32 {})
    |                      ^ expected one of 7 possible tokens
+   |
+   = help: enum variants can be `Variant`, `Variant = <integer>`, `Variant(Type, ..., TypeN)` or `Variant { fields: Types }`
+
+error: expected item, found `}`
+  --> $DIR/recover-enum2.rs:28:1
+   |
+LL | }
+   | ^ expected item
+   |
+   = note: for a full list of items that can appear in modules, see <https://doc.rust-lang.org/reference/items.html>
 
-error: aborting due to 2 previous errors
+error: aborting due to 3 previous errors
 

tests/ui/parser/recover/recover-for-loop-parens-around-head.stderr

@@ -4,24 +4,5 @@ error: expected one of `)`, `,`, `@`, or `|`, found keyword `in`
 LL |     for ( elem in vec ) {
    |                ^^ expected one of `)`, `,`, `@`, or `|`
 
-error: unexpected parentheses surrounding `for` loop head
-  --> $DIR/recover-for-loop-parens-around-head.rs:10:9
-   |
-LL |     for ( elem in vec ) {
-   |         ^             ^
-   |
-help: remove parentheses in `for` loop
-   |
-LL -     for ( elem in vec ) {
-LL +     for elem in vec {
-   |
-
-error[E0308]: mismatched types
-  --> $DIR/recover-for-loop-parens-around-head.rs:13:38
-   |
-LL |         const RECOVERY_WITNESS: () = 0;
-   |                                      ^ expected `()`, found integer
-
-error: aborting due to 3 previous errors
+error: aborting due to previous error
 
-For more information about this error, try `rustc --explain E0308`.

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

@@ -4,11 +4,5 @@ error: expected one of `)`, `,`, `...`, `..=`, `..`, or `|`, found keyword `if`
 LL |         (0 if true) => {
    |            ^^ expected one of `)`, `,`, `...`, `..=`, `..`, or `|`
 
-error: expected one of `.`, `=>`, `?`, or an operator, found `)`
-  --> $DIR/recover-parens-around-match-arm-head.rs:4:19
-   |
-LL |         (0 if true) => {
-   |                   ^ expected one of `.`, `=>`, `?`, or an operator
-
-error: aborting due to 2 previous errors
+error: aborting due to previous error