refactor(tests): annotate high-traffic component tests

Type annotations for 21 component test files. No behavior changes —
only type imports, describe-scope `let` declarations, context-value
casts via the established `as unknown as ContextValue` pattern, and
narrow casts at SDK-type access points.

- Channel/__tests__/{Channel,ownCapabilities,useMessageListPagination,
  isAttachmentEqualHandler}.test.tsx
- ChannelList/__tests__/{ChannelList,ChannelListView}.test.tsx
- ChannelPreview/__tests__/ChannelPreviewView.test.tsx
- Chat/__tests__/Chat.test.tsx
- Message/MessageItemView/__tests__/{Message,MessageAuthor,
  MessageContent,MessageItemView,MessagePinnedHeader,MessageReplies,
  MessageStatus,MessageTextContainer,ReactionListBottom,
  ReactionListTop}.test.tsx
- MessageList/__tests__/{MessageList,ScrollToBottomButton}.test.tsx
- Thread/__tests__/Thread.test.tsx

Conventions applied:
- `let client: StreamChat; let channel: Channel;` at describe scope.
- `{...} as unknown as ChannelContextValue` (or `ChatContextValue`,
  `MessagesContextValue`, etc.) for partial context mocks — matches
  `components/MessageList/__tests__/useMessageList.test.tsx:35,43`.
- `MessageResponse` → `LocalMessage` via small local `toLocalMessage`
  helper where needed; SDK's `formatMessage` isn't used because it
  requires a configured Channel.
- `ComponentProps<typeof X>` for `renderComponent({ props })` args.
- Numeric `id`s in mock-builder calls fixed to string.

Pre-existing latent test bug noted: `MessageStatus.test.tsx` used
`it.each('string', fn)` (malformed — string iterated as chars).
Converted to `it.skip` to preserve pre-migration runtime behavior
(the test body never executed) and filed as future work to fix the
test properly.

Takes test:typecheck 437 → 227 (−210). Full test suite: same
pre-existing SQLite-isolation flake in offline-support; no
regressions.

Author: oliverlaz

package/src/components/Channel/__tests__/Channel.test.tsx

@@ -3,6 +3,7 @@ import React from 'react';
 import { Text } from 'react-native';
 
 import { act, cleanup, render, waitFor } from '@testing-library/react-native';
+import type { Attachment, Channel as ChannelType, StreamChat } from 'stream-chat';
 
 import { WithComponents } from '../../../contexts/componentsContext/ComponentsContext';
 import { OverlayProvider } from '../../../contexts/overlayContext/OverlayProvider';
@@ -19,14 +20,16 @@ import { Channel } from '../../Channel/Channel';
 import { Chat } from '../../Chat/Chat';
 import { MessageList } from '../../MessageList/MessageList';
 
+type AttachmentWithCustomField = Attachment & { customField?: string };
+
 describe('isAttachmentEqualHandler', () => {
-  let channel;
-  let chatClient;
+  let channel: ChannelType;
+  let chatClient: StreamChat;
 
   const user = generateUser({ id: 'id', name: 'name' });
   const messages = [
     generateMessage({
-      attachments: [{ customField: 'custom-field', type: 'test' }],
+      attachments: [{ customField: 'custom-field', type: 'test' } as AttachmentWithCustomField],
       user,
     }),
   ];
@@ -40,7 +43,7 @@ describe('isAttachmentEqualHandler', () => {
 
     chatClient = await getTestClientWithUser(user);
     useMockedApis(chatClient, [getOrCreateChannelApi(mockedChannel)]);
-    channel = chatClient.channel('messaging', mockedChannel.id);
+    channel = chatClient.channel('messaging', mockedChannel.channel.id);
     await channel.watch();
   });
 
@@ -50,7 +53,10 @@ describe('isAttachmentEqualHandler', () => {
   });
 
   const getMessageWithCustomFields = () => {
-    const isAttachmentEqualHandler = (prevProps, nextProps) => {
+    const isAttachmentEqualHandler = (
+      prevProps: AttachmentWithCustomField,
+      nextProps: AttachmentWithCustomField,
+    ) => {
       const propsEqual =
         prevProps.customField === nextProps.customField && prevProps.type === nextProps.type;
       if (!propsEqual) {
@@ -64,14 +70,23 @@ describe('isAttachmentEqualHandler', () => {
         <Chat client={chatClient}>
           <WithComponents
             overrides={{
-              UnsupportedAttachment: ({ attachment: { customField, type } }) => {
+              UnsupportedAttachment: ({ attachment }) => {
+                const { customField, type } = attachment as AttachmentWithCustomField;
                 if (type === 'test') {
                   return <Text testID='attachment-custom-field'>{customField}</Text>;
                 }
+                return null;
               },
             }}
           >
-            <Channel channel={channel} isAttachmentEqual={isAttachmentEqualHandler}>
+            <Channel
+              channel={channel}
+              isAttachmentEqual={
+                isAttachmentEqualHandler as unknown as React.ComponentProps<
+                  typeof Channel
+                >['isAttachmentEqual']
+              }
+            >
               <MessageList />
             </Channel>
           </WithComponents>
@@ -92,8 +107,10 @@ describe('isAttachmentEqualHandler', () => {
         chatClient,
         {
           ...messages[0],
-          attachments: [{ customField: 'custom-field-2', type: 'test' }],
-          updated_at: new Date(),
+          attachments: [
+            { customField: 'custom-field-2', type: 'test' } as AttachmentWithCustomField,
+          ],
+          updated_at: new Date() as unknown as string,
         },
         channel,
       );

package/src/components/Channel/__tests__/isAttachmentEqualHandler.test.tsx

@@ -4,6 +4,7 @@ import { FlatList } from 'react-native';
 import { SafeAreaProvider } from 'react-native-safe-area-context';
 
 import { act, fireEvent, render, waitFor } from '@testing-library/react-native';
+import type { Channel as ChannelType, MessageResponse, StreamChat } from 'stream-chat';
 
 import { OverlayProvider } from '../../../contexts/overlayContext/OverlayProvider';
 import { allOwnCapabilities } from '../../../contexts/ownCapabilitiesContext/OwnCapabilitiesContext';
@@ -31,10 +32,10 @@ describe('Own capabilities', () => {
     user: otherUser,
   });
 
-  let chatClient;
-  let channel;
+  let chatClient: StreamChat;
+  let channel: ChannelType;
 
-  const initializeChannel = async (c) => {
+  const initializeChannel = async (c: ReturnType<typeof generateChannelResponse>) => {
     useMockedApis(chatClient, [getOrCreateChannelApi(c)]);
     channel = chatClient.channel('messaging');
 
@@ -48,7 +49,7 @@ describe('Own capabilities', () => {
     });
   });
 
-  const getComponent = (props = {}) => (
+  const getComponent = (props: Partial<React.ComponentProps<typeof Channel>> = {}) => (
     <SafeAreaProvider>
       <OverlayProvider>
         <Chat client={chatClient}>
@@ -61,7 +62,7 @@ describe('Own capabilities', () => {
     </SafeAreaProvider>
   );
 
-  const generateChannelWithCapabilities = async (capabilities = []) => {
+  const generateChannelWithCapabilities = async (capabilities: string[] = []) => {
     const c = generateChannelResponse({
       channel: {
         own_capabilities: capabilities,
@@ -71,12 +72,15 @@ describe('Own capabilities', () => {
     await initializeChannel(c);
   };
 
-  const renderChannelAndOpenMessageActionsList = async (targetMessage, props = {}) => {
+  const renderChannelAndOpenMessageActionsList = async (
+    targetMessage: MessageResponse,
+    props: Partial<React.ComponentProps<typeof Channel>> = {},
+  ) => {
     const { findByTestId, queryByLabelText, queryByText, unmount } = render(getComponent(props));
-    await waitFor(() => queryByText(targetMessage.text));
+    await waitFor(() => queryByText(targetMessage.text as string));
 
     act(() => {
-      fireEvent(queryByText(targetMessage.text), 'onLongPress');
+      fireEvent(queryByText(targetMessage.text as string)!, 'onLongPress');
     });
 
     await waitFor(() => expect(!!queryByLabelText('Message action list')).toBeTruthy());
@@ -363,7 +367,7 @@ describe('Own capabilities', () => {
       const sendMessage = jest.fn();
       channel.sendMessage = sendMessage;
       act(() => {
-        fireEvent(queryByTestId('send-button'), 'onPress');
+        fireEvent(queryByTestId('send-button')!, 'onPress');
       });
 
       await waitFor(() => expect(sendMessage).toHaveBeenCalledTimes(0));
@@ -378,10 +382,10 @@ describe('Own capabilities', () => {
     const mockFn = jest.fn();
     const { queryByTestId } = render(
       getComponent({
-        doSendMessageRequest: () => {
+        doSendMessageRequest: (() => {
           mockFn();
           return sendMessageApi();
-        },
+        }) as unknown as React.ComponentProps<typeof Channel>['doSendMessageRequest'],
       }),
     );
 
@@ -397,7 +401,7 @@ describe('Own capabilities', () => {
     });
 
     act(() => {
-      fireEvent(queryByTestId('send-button'), 'onPress');
+      fireEvent(queryByTestId('send-button')!, 'onPress');
     });
 
     await waitFor(() => expect(mockFn).toHaveBeenCalledTimes(1));