Properly normalize very old chat session data (#227030)

Fix microsoft/vscode-copilot#7729

src/vs/workbench/contrib/chat/common/chatModel.ts

@@ -616,6 +616,8 @@ export type ISerializableChatDataIn = ISerializableChatData1 | ISerializableChat
  * TODO- ChatModel#_deserialize and reviveSerializedAgent also still do some normalization and maybe that should be done in here too.
  */
 export function normalizeSerializableChatData(raw: ISerializableChatDataIn): ISerializableChatData {
+	normalizeOldFields(raw);
+
 	if (!('version' in raw)) {
 		return {
 			version: 3,
@@ -636,6 +638,30 @@ export function normalizeSerializableChatData(raw: ISerializableChatDataIn): ISe
 	return raw;
 }
 
+function normalizeOldFields(raw: ISerializableChatDataIn): void {
+	// Fill in fields that very old chat data may be missing
+	if (!raw.sessionId) {
+		raw.sessionId = generateUuid();
+	}
+
+	if (!raw.creationDate) {
+		raw.creationDate = getLastYearDate();
+	}
+
+	if ('version' in raw && (raw.version === 2 || raw.version === 3)) {
+		if (!raw.lastMessageDate) {
+			// A bug led to not porting creationDate properly, and that was copied to lastMessageDate, so fix that up if missing.
+			raw.lastMessageDate = getLastYearDate();
+		}
+	}
+}
+
+function getLastYearDate(): number {
+	const lastYearDate = new Date();
+	lastYearDate.setFullYear(lastYearDate.getFullYear() - 1);
+	return lastYearDate.getTime();
+}
+
 export function isExportableSessionData(obj: unknown): obj is IExportableChatData {
 	const data = obj as IExportableChatData;
 	return typeof data === 'object' &&

src/vs/workbench/contrib/chat/test/common/chatModel.test.ts

@@ -17,7 +17,7 @@ import { MockContextKeyService } from 'vs/platform/keybinding/test/common/mockKe
 import { ILogService, NullLogService } from 'vs/platform/log/common/log';
 import { IStorageService } from 'vs/platform/storage/common/storage';
 import { ChatAgentLocation, ChatAgentService, IChatAgentService } from 'vs/workbench/contrib/chat/common/chatAgents';
-import { ChatModel, ISerializableChatData1, ISerializableChatData2, normalizeSerializableChatData, Response } from 'vs/workbench/contrib/chat/common/chatModel';
+import { ChatModel, ISerializableChatData1, ISerializableChatData2, ISerializableChatData3, normalizeSerializableChatData, Response } from 'vs/workbench/contrib/chat/common/chatModel';
 import { ChatRequestTextPart } from 'vs/workbench/contrib/chat/common/chatParserTypes';
 import { IExtensionService } from 'vs/workbench/services/extensions/common/extensions';
 import { TestExtensionService, TestStorageService } from 'vs/workbench/test/common/workbenchTestServices';
@@ -230,4 +230,53 @@ suite('normalizeSerializableChatData', () => {
 		assert.strictEqual(newData.lastMessageDate, v2Data.lastMessageDate);
 		assert.strictEqual(newData.customTitle, v2Data.computedTitle);
 	});
+
+	test('old bad data', () => {
+		const v1Data: ISerializableChatData1 = {
+			// Testing the scenario where these are missing
+			sessionId: undefined!,
+			creationDate: undefined!,
+
+			initialLocation: undefined,
+			isImported: false,
+			requesterAvatarIconUri: undefined,
+			requesterUsername: 'me',
+			requests: [],
+			responderAvatarIconUri: undefined,
+			responderUsername: 'bot',
+			welcomeMessage: []
+		};
+
+		const newData = normalizeSerializableChatData(v1Data);
+		assert.strictEqual(newData.version, 3);
+		assert.ok(newData.creationDate > 0);
+		assert.ok(newData.lastMessageDate > 0);
+		assert.ok(newData.sessionId);
+	});
+
+	test('v3 with bug', () => {
+		const v3Data: ISerializableChatData3 = {
+			// Test case where old data was wrongly normalized and these fields were missing
+			creationDate: undefined!,
+			lastMessageDate: undefined!,
+
+			version: 3,
+			initialLocation: undefined,
+			isImported: false,
+			requesterAvatarIconUri: undefined,
+			requesterUsername: 'me',
+			requests: [],
+			responderAvatarIconUri: undefined,
+			responderUsername: 'bot',
+			sessionId: 'session1',
+			welcomeMessage: [],
+			customTitle: 'computed title'
+		};
+
+		const newData = normalizeSerializableChatData(v3Data);
+		assert.strictEqual(newData.version, 3);
+		assert.ok(newData.creationDate > 0);
+		assert.ok(newData.lastMessageDate > 0);
+		assert.ok(newData.sessionId);
+	});
 });