Fix nested bindings in queries (#927)

Cherry-picked from
bb92384.
We need this for 0.14 to allow for more interesting queries for
NomicFoundation/hardhat-vscode#547.

Co-authored-by: Antony Blakey <antony@nomic.foundation>

crates/codegen/parser/runtime/src/query/engine.rs

@@ -181,6 +181,7 @@ impl Combinator for BindingCombinator {
             .entry(self.matcher.name.clone())
             .or_default()
             .push(self.cursor.clone());
+        self.child.accumulate_bindings(bindings);
     }
 }
 

crates/testlang/outputs/cargo/tests/src/query/engine_tests.rs

@@ -250,3 +250,14 @@ fn test_optional() {
         },
     );
 }
+
+#[test]
+fn test_nested() {
+    run_query_test(
+        &common_test_tree(),
+        "@root [TreeNode ... @z [DelimitedIdentifier] [_] ]",
+        query_results! {
+            {root: ["ABCDE"], z: ["C"]}
+        },
+    );
+}