refactor: move check if is thread main message to other hook

apps/meteor/client/views/room/MessageList/MessageList.tsx

@@ -16,6 +16,7 @@ import { isMessageFirstUnread } from './lib/isMessageFirstUnread';
 import { isMessageNewDay } from './lib/isMessageNewDay';
 import { isMessageSequential } from './lib/isMessageSequential';
 import { isOwnUserMessage } from './lib/isOwnUserMessage';
+import { isPreviousThreadMainMessage } from './lib/isPreviousThreadMainMessage';
 import MessageHighlightProvider from './providers/MessageHighlightProvider';
 import { MessageListProvider } from './providers/MessageListProvider';
 
@@ -45,9 +46,10 @@ export const MessageList = ({ rid }: MessageListProps): ReactElement => {
 								const isNewDay = isMessageNewDay(message, previous);
 								const isFirstUnread = isMessageFirstUnread(subscription, message, previous);
 								const isUserOwnMessage = isOwnUserMessage(message, subscription);
+								const isPreviousThreadShow = isPreviousThreadMainMessage(previous);
 								const shouldShowDivider = isNewDay || isFirstUnread;
 
-								const shouldShowAsSequential = isSequential && !isNewDay;
+								const shouldShowAsSequential = isSequential && !isNewDay && !isPreviousThreadShow;
 
 								const isSystemMessage = MessageTypes.isSystemMessage(message);
 								const shouldShowMessage = !isThreadMessage(message) && !isSystemMessage;

apps/meteor/client/views/room/MessageList/lib/isMessageSequential.ts

@@ -1,4 +1,4 @@
-import { IMessage, isThreadMessage } from '@rocket.chat/core-typings';
+import { IMessage } from '@rocket.chat/core-typings';
 import { differenceInSeconds } from 'date-fns';
 
 import { MessageTypes } from '../../../../../app/ui-utils/lib/MessageTypes';
@@ -28,9 +28,5 @@ export const isMessageSequential = (current: IMessage, previous: IMessage | unde
 		return false;
 	}
 
-	if (isThreadMessage(previous) && previous.tshow) {
-		return false;
-	}
-
 	return differenceInSeconds(current.ts, previous.ts) < groupingRange;
 };

apps/meteor/client/views/room/MessageList/lib/isPreviousThreadMainMessage.tsx

@@ -0,0 +1,4 @@
+import { IMessage, isThreadMessage } from '@rocket.chat/core-typings';
+
+export const isPreviousThreadMainMessage = (previous: IMessage | undefined): boolean =>
+	!!previous && !!previous.tshow && isThreadMessage(previous);

apps/meteor/tests/unit/client/views/room/MessageList/lib/isMessageSequential.spec.ts

@@ -1,5 +1,5 @@
 /* eslint-env mocha */
-import type { IMessage, IThreadMessage } from '@rocket.chat/core-typings';
+import type { IMessage } from '@rocket.chat/core-typings';
 import { expect } from 'chai';
 
 import { MessageTypes } from '../../../../../../../app/ui-utils/lib/MessageTypes';
@@ -141,16 +141,4 @@ describe('isMessageSequential', () => {
 		};
 		expect(isMessageSequential(current, previous, TIME_RANGE_IN_SECONDS)).to.be.false;
 	});
-
-	it('should return false if previous message is thread preview', () => {
-		const previous: IThreadMessage = {
-			...baseMessage,
-			tmid: 'threadId',
-			tshow: true,
-		};
-		const current: IMessage = {
-			...baseMessage,
-		};
-		expect(isMessageSequential(current, previous, TIME_RANGE_IN_SECONDS)).to.be.false;
-	});
 });

apps/meteor/tests/unit/client/views/room/MessageList/lib/isPreviousThreadShowMessage.spec.ts

@@ -0,0 +1,39 @@
+/* eslint-env mocha */
+import type { IThreadMessage } from '@rocket.chat/core-typings';
+import { expect } from 'chai';
+
+import { isPreviousThreadMainMessage } from '../../../../../../../client/views/room/MessageList/lib/isPreviousThreadMainMessage';
+
+const date = new Date('2021-10-27T00:00:00.000Z');
+const baseMessage = {
+	ts: date,
+	u: {
+		_id: 'userId',
+		name: 'userName',
+		username: 'userName',
+	},
+	msg: 'message',
+	rid: 'roomId',
+	_id: 'messageId',
+	_updatedAt: date,
+	urls: [],
+};
+
+describe('isPreviousThreadMainMessage', () => {
+	it('should return false if no previous message', () => {
+		expect(isPreviousThreadMainMessage(undefined)).to.be.false;
+	});
+
+	it('should return false if previous message is not thread preview', () => {
+		expect(isPreviousThreadMainMessage(baseMessage)).to.be.false;
+	});
+
+	it('should return true if previous message is thread preview', () => {
+		const previous: IThreadMessage = {
+			...baseMessage,
+			tmid: 'threadId',
+			tshow: true,
+		};
+		expect(isPreviousThreadMainMessage(previous)).to.be.true;
+	});
+});