chore: add unowned signals test

packages/svelte/tests/signals/test.ts

@@ -574,4 +574,40 @@ describe('signals', () => {
  assert.equal(d.deps?.length, 1);
  };
  });
+
+ test('unowned deriveds are correctly connected and disconnected from the graph', () => {
+ var count = source(0);
+
+ function create_derived() {
+ return derived(() => $.get(count) * 2);
+ }
+
+ return () => {
+ let d = create_derived();
+
+ const destroy = effect_root(() => {
+ render_effect(() => {
+ assert.equal($.get(d), 0);
+ });
+ });
+
+ assert.equal($.get(d), 0);
+ assert.equal(count.reactions?.length, 1);
+ assert.equal(d.deps?.length, 1);
+
+ set(count, 1);
+ assert.equal($.get(d), 2);
+ assert.equal(count.reactions?.length, 1);
+ assert.equal(d.deps?.length, 1);
+
+ destroy();
+
+ assert.equal(count.reactions, null);
+
+ set(count, 2);
+ assert.equal($.get(d), 4);
+ assert.equal(count.reactions, null);
+ assert.equal(d.deps?.length, 1);
+ };
+ });
 });