test(browser): add tests locking in wait_until defaults for navigate_back/go_forward

Co-authored-by: OhYee <13498329+OhYee@users.noreply.github.com>

Author: Copilot

tests/unittests/integration/test_browser_toolset_error_handling.py

@@ -520,3 +520,27 @@ def callback(sb):
         assert "error" in result
         toolset._reset_playwright.assert_not_called()
         assert toolset.sandbox is original_sandbox
+
+
+class TestBrowserNavigationDefaults:
+    """测试导航方法的默认参数 / Tests for default parameters of navigation methods"""
+
+    def test_browser_navigate_back_default_wait_until(self):
+        """browser_navigate_back 的默认 wait_until 为 domcontentloaded"""
+        fields = BrowserToolSet.browser_navigate_back.args_schema.model_fields
+        assert fields["wait_until"].default == "domcontentloaded"
+
+    def test_browser_go_forward_default_wait_until(self):
+        """browser_go_forward 的默认 wait_until 为 domcontentloaded"""
+        fields = BrowserToolSet.browser_go_forward.args_schema.model_fields
+        assert fields["wait_until"].default == "domcontentloaded"
+
+    def test_browser_navigate_back_default_timeout_is_none(self):
+        """browser_navigate_back 的默认 timeout 为 None"""
+        fields = BrowserToolSet.browser_navigate_back.args_schema.model_fields
+        assert fields["timeout"].default is None
+
+    def test_browser_go_forward_default_timeout_is_none(self):
+        """browser_go_forward 的默认 timeout 为 None"""
+        fields = BrowserToolSet.browser_go_forward.args_schema.model_fields
+        assert fields["timeout"].default is None