8 files changed, 67 insertions, 8 deletions

diff --git a/crates/libsyntax2/src/grammar/items/mod.rs b/crates/libsyntax2/src/grammar/items/mod.rs
index 32d0778c4..a285892df 100644
--- a/crates/libsyntax2/src/grammar/items/mod.rs
+++ b/crates/libsyntax2/src/grammar/items/mod.rs
@@ -43,7 +43,12 @@ pub(super) fn item_or_macro(p: &mut Parser, stop_on_r_curly: bool, flavor: ItemF
                 m.abandon(p);
                 if p.at(L_CURLY) {
                     error_block(p, "expected an item");
-                } else if !p.at(EOF) && !(stop_on_r_curly && p.at(R_CURLY)) {
+                } else if p.at(R_CURLY) && !stop_on_r_curly {
+                    let e = p.start();
+                    p.error("unmatched `}`");
+                    p.bump();
+                    e.complete(p, ERROR);
+                } else if !p.at(EOF) && !p.at(R_CURLY) {
                     p.err_and_bump("expected an item");
                 } else {
                     p.error("expected an item");
diff --git a/crates/libsyntax2/src/lib.rs b/crates/libsyntax2/src/lib.rs
index 9ba9970c9..93057dd6a 100644
--- a/crates/libsyntax2/src/lib.rs
+++ b/crates/libsyntax2/src/lib.rs
@@ -127,12 +127,12 @@ fn validate_block_structure(root: SyntaxNodeRef) {
                     assert_eq!(
                         node.parent(),
                         pair.parent(),
-                        "unpaired curleys:\n{}",
+                        "\nunpaired curleys:\n{}",
                         utils::dump_tree(root),
                     );
                     assert!(
                         node.next_sibling().is_none() && pair.prev_sibling().is_none(),
-                        "floating curlys at {:?}\nfile:\n{}\nerror:\n{}\n",
+                        "\nfloating curlys at {:?}\nfile:\n{}\nerror:\n{}\n",
                         node,
                         root.text(),
                         node.text(),
diff --git a/crates/libsyntax2/src/parser_api.rs b/crates/libsyntax2/src/parser_api.rs
index bb34fe973..0a3b29b70 100644
--- a/crates/libsyntax2/src/parser_api.rs
+++ b/crates/libsyntax2/src/parser_api.rs
@@ -141,7 +141,9 @@ impl<'t> Parser<'t> {
     pub(crate) fn err_and_bump(&mut self, message: &str) {
         let m = self.start();
         self.error(message);
-        self.bump();
+        if !self.at(SyntaxKind::L_CURLY) && !self.at(SyntaxKind::R_CURLY) {
+            self.bump();
+        }
         m.complete(self, ERROR);
     }
 }
diff --git a/crates/libsyntax2/tests/data/parser/err/0007_stray_curly_in_file.txt b/crates/libsyntax2/tests/data/parser/err/0007_stray_curly_in_file.txt
index 81e82f7e2..802c69b31 100644
--- a/crates/libsyntax2/tests/data/parser/err/0007_stray_curly_in_file.txt
+++ b/crates/libsyntax2/tests/data/parser/err/0007_stray_curly_in_file.txt
@@ -1,7 +1,7 @@
 ROOT@[0; 31)
   ERROR@[0; 1)
     R_CURLY@[0; 1)
-    err: `expected an item`
+    err: `unmatched `}``
   WHITESPACE@[1; 3)
   STRUCT_DEF@[3; 12)
     STRUCT_KW@[3; 9)
@@ -10,7 +10,7 @@ ROOT@[0; 31)
       IDENT@[10; 11) "S"
     SEMI@[11; 12)
   WHITESPACE@[12; 14)
-  err: `expected an item`
+  err: `unmatched `}``
   ERROR@[14; 15)
     R_CURLY@[14; 15)
   WHITESPACE@[15; 17)
@@ -26,7 +26,7 @@ ROOT@[0; 31)
       L_CURLY@[25; 26)
       R_CURLY@[26; 27)
   WHITESPACE@[27; 29)
-  err: `expected an item`
+  err: `unmatched `}``
   ERROR@[29; 30)
     R_CURLY@[29; 30)
   WHITESPACE@[30; 31)
diff --git a/crates/libsyntax2/tests/data/parser/err/0015_curly_in_params.txt b/crates/libsyntax2/tests/data/parser/err/0015_curly_in_params.txt
index dbc19abea..5f736a978 100644
--- a/crates/libsyntax2/tests/data/parser/err/0015_curly_in_params.txt
+++ b/crates/libsyntax2/tests/data/parser/err/0015_curly_in_params.txt
@@ -9,7 +9,7 @@ ROOT@[0; 14)
       err: `expected value parameter`
       err: `expected R_PAREN`
       err: `expected a block`
-      err: `expected an item`
+      err: `unmatched `}``
   ERROR@[7; 8)
     R_CURLY@[7; 8)
     err: `expected an item`
diff --git a/crates/libsyntax2/tests/data/parser/err/0017_incomplete_binexpr.rs b/crates/libsyntax2/tests/data/parser/err/0017_incomplete_binexpr.rs
new file mode 100644
index 000000000..17bd49777
--- /dev/null
+++ b/crates/libsyntax2/tests/data/parser/err/0017_incomplete_binexpr.rs
@@ -0,0 +1,4 @@
+fn foo(foo: i32) {
+    let bar = 92;
+    1 +
+}
diff --git a/crates/libsyntax2/tests/data/parser/err/0017_incomplete_binexpr.txt b/crates/libsyntax2/tests/data/parser/err/0017_incomplete_binexpr.txt
new file mode 100644
index 000000000..db9a2f175
--- /dev/null
+++ b/crates/libsyntax2/tests/data/parser/err/0017_incomplete_binexpr.txt
@@ -0,0 +1,47 @@
+ROOT@[0; 47)
+  FN_DEF@[0; 46)
+    FN_KW@[0; 2)
+    WHITESPACE@[2; 3)
+    NAME@[3; 6)
+      IDENT@[3; 6) "foo"
+    PARAM_LIST@[6; 16)
+      L_PAREN@[6; 7)
+      PARAM@[7; 15)
+        BIND_PAT@[7; 10)
+          NAME@[7; 10)
+            IDENT@[7; 10) "foo"
+        COLON@[10; 11)
+        WHITESPACE@[11; 12)
+        PATH_TYPE@[12; 15)
+          PATH@[12; 15)
+            PATH_SEGMENT@[12; 15)
+              NAME_REF@[12; 15)
+                IDENT@[12; 15) "i32"
+      R_PAREN@[15; 16)
+    WHITESPACE@[16; 17)
+    BLOCK@[17; 46)
+      L_CURLY@[17; 18)
+      WHITESPACE@[18; 23)
+      LET_STMT@[23; 36)
+        LET_KW@[23; 26)
+        WHITESPACE@[26; 27)
+        BIND_PAT@[27; 30)
+          NAME@[27; 30)
+            IDENT@[27; 30) "bar"
+        WHITESPACE@[30; 31)
+        EQ@[31; 32)
+        WHITESPACE@[32; 33)
+        LITERAL@[33; 35)
+          INT_NUMBER@[33; 35) "92"
+        SEMI@[35; 36)
+      WHITESPACE@[36; 41)
+      BIN_EXPR@[41; 45)
+        LITERAL@[41; 42)
+          INT_NUMBER@[41; 42) "1"
+        WHITESPACE@[42; 43)
+        PLUS@[43; 44)
+        WHITESPACE@[44; 45)
+        err: `expected expression`
+        ERROR@[45; 45)
+      R_CURLY@[45; 46)
+  WHITESPACE@[46; 47)
diff --git a/crates/libsyntax2/tests/test/main.rs b/crates/libsyntax2/tests/test/main.rs
index 596f32216..9958c7ece 100644
--- a/crates/libsyntax2/tests/test/main.rs
+++ b/crates/libsyntax2/tests/test/main.rs
@@ -26,6 +26,7 @@ fn lexer_tests() {
 #[test]
 fn parser_tests() {
     dir_tests(&["parser/inline", "parser/ok", "parser/err"], |text| {
+        eprintln!("\n{}\n", text);
         let file = File::parse(text);
         dump_tree(file.syntax())
     })