Add test for find_var_htab scope_level regression

Author: jiang1997

tests/test_find_var_htab.js

@@ -0,0 +1,20 @@
+import { assert } from "./assert.js";
+
+// Regression test for find_var_htab: when a var shadows a block-scoped
+// let of the same name, the htab probe must skip entries with
+// scope_level != 0. 28 vars are needed to trigger the htab path.
+function test_find_var_htab() {
+    { let x = "let"; }
+    var v0, v1, v2, v3, v4, v5, v6, v7, v8, v9;
+    var v10, v11, v12, v13, v14, v15, v16, v17, v18, v19;
+    var v20, v21, v22, v23, v24, v25, v26;
+    var x = "var";
+
+    function closure() {
+        return x;
+    }
+
+    assert(closure(), "var", "find_var_htab returned wrong slot index");
+}
+
+test_find_var_htab();