diff --git a/src/test/parser.rs b/src/test/parser.rs
index 903d4e48625..d86c172192d 100644
--- a/src/test/parser.rs
+++ b/src/test/parser.rs
@@ -69,3 +69,10 @@ fn crate_parsing_stashed_diag2() {
     let filename = "tests/parser/stashed-diag2.rs";
     assert_parser_error(filename);
 }
+
+#[test]
+fn parser_error_const_missing_type() {
+    // See also https://github.com/rust-lang/rustfmt/issues/6099
+    let filename = "tests/parser/issue-6099.rs";
+    assert_parser_error(filename);
+}
diff --git a/tests/parser/issue-6099.rs b/tests/parser/issue-6099.rs
new file mode 100644
index 00000000000..8de0f36b079
--- /dev/null
+++ b/tests/parser/issue-6099.rs
@@ -0,0 +1 @@
+const BAR = 42;
\ No newline at end of file