From b18265951973dfb1e8ba236e8a80c6f3ee51345f Mon Sep 17 00:00:00 2001
From: Huanyi Xie <74809554+xiehuanyi@users.noreply.github.com>
Date: Mon, 5 Oct 2026 17:40:36 +0300
Subject: [PATCH] test(cpp): distinguish union methods from data fields

Assisted-by: OpenAI Codex (GPT-6)
(cherry picked from commit 0a7c77cb6339b099dc3fe7312a4e2e46c20e23a7)
---
 tests/test_cpp_nested_and_cli.py | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/tests/test_cpp_nested_and_cli.py b/tests/test_cpp_nested_and_cli.py
index 300e5a589..1f5ddcc8c 100644
--- a/tests/test_cpp_nested_and_cli.py
+++ b/tests/test_cpp_nested_and_cli.py
@@ -123,6 +123,21 @@ def test_cpp_union_specifier_is_extracted(tmp_path):
     assert "Anon" not in labels
 
 
+def test_cpp_union_member_function_is_a_method(tmp_path):
+    """A union's method declaration must not become a data field."""
+    source = tmp_path / "value.hpp"
+    source.write_text("union Value { int i; int get() const; };\n", encoding="utf-8")
+    result = extract_cpp(source)
+    assert result.get("parse_errors") is None
+    labels = {n["id"]: n["label"] for n in result["nodes"]}
+    relationships = {(labels.get(e["source"]), labels.get(e["target"]), e["relation"])
+                     for e in result["edges"]}
+    assert ("Value", ".get()", "method") in relationships
+    assert ("Value", "i", "defines") in relationships
+    assert ("Value", "get", "defines") not in relationships
+    assert "get" not in labels.values()
+
+
 def test_nested_cpp_class_is_extracted(tmp_path):
     # A nested type is a field_declaration whose `type` field IS the
     # class_specifier; the member-variable branch used to consume it and return