small test for the optional chaining operator

Author: rbri

src/test/java/org/htmlunit/corejs/OptionalChainingOperatorTest.java

@@ -0,0 +1,53 @@
+/*
+ * Copyright (c) 2002-2025 Gargoyle Software Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.htmlunit.corejs;
+
+import org.junit.jupiter.api.Test;
+
+/**
+ * Tests for the optional chaining operator (?.).
+ *
+ * @author Ronald Brill
+ */
+public class OptionalChainingOperatorTest {
+
+    /**
+     * @throws Exception if the test fails
+     */
+    @Test
+    public void basic() throws Exception {
+        final String script = "var res = ''\n"
+                + "  var o = { a: 'one', b: { c: 'two' }};\n"
+                + "  res += o.x?.c;\n"
+                + "  res += ' ';\n"
+                + "  res += o.b?.c;\n"
+                + "res";
+
+        Utils.assertWithAllModes_ES6("undefined two", script);
+    }
+
+    /**
+     * @throws Exception if the test fails
+     */
+    @Test
+    public void parse() throws Exception {
+        final String script = "var res = ''\n"
+                + "  var o = {a: true};\n"
+                + "  res += o?.['a'];\n"
+                + "res";
+
+        Utils.assertWithAllModes_ES6("true", script);
+    }
+}