[6.x] Persist Replicator set collapse state to meta

resources/js/components/fieldtypes/replicator/Replicator.vue

@@ -387,8 +387,11 @@ export default {
             }, 1);
         },
 
-        collapsed(collapsed) {
-            this.updateMeta({ ...this.meta, collapsed: clone(collapsed) });
+        collapsed: {
+            deep: true,
+            handler(collapsed) {
+                this.updateMeta({ ...this.meta, collapsed: clone(collapsed) });
+            },
         },
 
         loadingSet(loading) {

resources/js/tests/components/fieldtypes/replicator/Replicator.test.js

@@ -0,0 +1,66 @@
+import { mount } from '@vue/test-utils';
+import { beforeEach, expect, test, vi } from 'vitest';
+import * as Globals from '@/bootstrap/globals';
+import Replicator from '@/components/fieldtypes/replicator/Replicator.vue';
+import { containerContextKey } from '@/components/ui/Publish/Container.vue';
+
+Object.keys(Globals).forEach((fn) => (window[fn] = Globals[fn]));
+window.__ = (key) => key;
+window.__n = (key, count) => key.split('|')[count === 1 ? 0 : 1].replace(/:count/g, count);
+
+const sets = [
+    { _id: 'set-1', type: 'card', enabled: true },
+    { _id: 'set-2', type: 'card', enabled: true },
+];
+
+function mountField(collapsed) {
+    return mount(Replicator, {
+        shallow: true,
+        props: {
+            value: sets,
+            handle: 'blocks',
+            config: { collapse: true, sets: [{ handle: 'main', sets: [{ handle: 'card', fields: [] }] }] },
+            meta: { existing: { 'set-1': {}, 'set-2': {} }, collapsed, defaults: {}, new: {} },
+        },
+        global: {
+            mocks: {
+                $keys: { bindGlobal: () => ({ destroy: () => {} }) },
+                $progress: { loading: () => {} },
+            },
+            provide: {
+                [containerContextKey]: {
+                    values: { value: {} },
+                    errors: { value: {} },
+                    setFieldValue: vi.fn(),
+                    setFieldMeta: vi.fn(),
+                },
+            },
+        },
+    });
+}
+
+function lastMeta(wrapper) {
+    return wrapper.emitted('update:meta').at(-1)[0];
+}
+
+beforeEach(() => {
+    window.Statamic = { $fieldActions: { get: () => [] } };
+});
+
+test('expanding a set persists the collapsed state to meta', async () => {
+    const wrapper = mountField(['set-1', 'set-2']);
+
+    wrapper.vm.expandSet('set-1');
+    await wrapper.vm.$nextTick();
+
+    expect(lastMeta(wrapper).collapsed).toEqual(['set-2']);
+});
+
+test('collapsing a set persists the collapsed state to meta', async () => {
+    const wrapper = mountField([]);
+
+    wrapper.vm.collapseSet('set-2');
+    await wrapper.vm.$nextTick();
+
+    expect(lastMeta(wrapper).collapsed).toEqual(['set-2']);
+});