fix(fuselage-ui-kit): `MultiStaticSelectElement` not working as expected (#32999)

Co-authored-by: Tasso Evangelista <2263066+tassoevan@users.noreply.github.com>

.changeset/mighty-drinks-hide.md

+---
+"@rocket.chat/meteor": patch
+"@rocket.chat/fuselage-ui-kit": patch
+---
+
+Fixes multiple selection for MultiStaticSelectElement in UiKit

apps/meteor/tests/e2e/apps/apps-modal.spec.ts

@@ -7,7 +7,7 @@ import { expect, test } from '../utils/test';
 
 test.use({ storageState: Users.user1.state });
 
-test.describe.serial('Apps > ContextualBar', () => {
+test.describe.serial('Apps > Modal', () => {
 	let poHomeChannel: HomeChannel;
 	let poModal: Modal;
 

packages/fuselage-ui-kit/src/hooks/useUiKitState.spec.ts

+import {
+  BlockContext,
+  type MultiStaticSelectElement,
+} from '@rocket.chat/ui-kit';
+import { act, renderHook } from '@testing-library/react';
+
+import { useUiKitState } from './useUiKitState';
+
+describe('state function', () => {
+  const context = BlockContext.NONE;
+
+  it('should handle arrays', async () => {
+    const element: MultiStaticSelectElement = {
+      type: 'multi_static_select',
+      placeholder: { type: 'plain_text', text: '' },
+      options: [],
+      initialValue: ['A', 'B'],
+      appId: 'app-id',
+      blockId: 'block-id',
+      actionId: 'action-id',
+    };
+
+    const { result } = renderHook(() => useUiKitState(element, context), {
+      legacyRoot: true,
+    });
+
+    await act(async () => {
+      const [, state] = result.current;
+      await state({
+        target: {
+          value: ['C', 'D'],
+        },
+      });
+    });
+
+    expect(result.current[0].value).toEqual(['C', 'D']);
+  });
+});
+
+describe('action function', () => {
+  const context = BlockContext.ACTION;
+
+  it('should handle arrays', async () => {
+    const element: MultiStaticSelectElement = {
+      type: 'multi_static_select',
+      placeholder: { type: 'plain_text', text: '' },
+      options: [],
+      initialValue: ['A', 'B'],
+      appId: 'app-id',
+      blockId: 'block-id',
+      actionId: 'action-id',
+    };
+
+    const { result } = renderHook(() => useUiKitState(element, context), {
+      legacyRoot: true,
+    });
+
+    await act(async () => {
+      const [, action] = result.current;
+      await action({
+        target: {
+          value: ['C', 'D'],
+        },
+      });
+    });
+
+    expect(result.current[0].value).toEqual(['C', 'D']);
+  });
+});

packages/fuselage-ui-kit/src/hooks/useUiKitState.ts

@@ -42,7 +42,7 @@ export const useUiKitState = <TElement extends UiKit.ActionableElement>(
       | Event
       | { target: EventTarget }
       | { target: { value: UiKit.ActionOf<TElement> } }
-  ) => void
+  ) => Promise<void>
 ] => {
   const { blockId, actionId, appId, dispatchActionConfig } = element;
   const {
@@ -70,15 +70,20 @@ export const useUiKitState = <TElement extends UiKit.ActionableElement>(
     const {
       target: { value: elValue },
     } = e;
+
     setLoading(true);
 
     if (Array.isArray(value)) {
-      const idx = value.findIndex((value) => value === elValue);
-
-      if (idx > -1) {
-        setValue(value.filter((_, i) => i !== idx));
+      if (Array.isArray(elValue)) {
+        setValue(elValue);
       } else {
-        setValue([...value, elValue]);
+        const idx = value.findIndex((value) => value === elValue);
+
+        if (idx > -1) {
+          setValue(value.filter((_, i) => i !== idx));
+        } else {
+          setValue([...value, elValue]);
+        }
       }
     } else {
       setValue(elValue);