Vendor things

third-party/vendor/swc_config/tests/derive_merge.rs

@@ -0,0 +1,24 @@
+use swc_config::merge::Merge;
+
+#[derive(Merge)]
+struct Fields {
+    a: Option<()>,
+}
+
+#[test]
+fn test_fields() {
+    let mut fields = Fields { a: None };
+    fields.merge(Fields { a: Some(()) });
+
+    assert_eq!(fields.a, Some(()));
+}
+
+#[derive(Merge)]
+struct Tuple(Option<()>);
+#[test]
+fn test_tuple() {
+    let mut tuple = Tuple(None);
+    tuple.merge(Tuple(Some(())));
+
+    assert_eq!(tuple.0, Some(()));
+}