fix(context): Fix snapshot recovery across sessions. (#26939)

packages/cli/src/config/config.ts

@@ -103,6 +103,7 @@ export interface CliArgs {
   useWriteTodos: boolean | undefined;
   outputFormat: string | undefined;
   fakeResponses: string | undefined;
+  fakeResponsesNonStrict?: string | undefined;
   recordResponses: string | undefined;
   startupMessages?: string[];
   rawOutput: boolean | undefined;
@@ -474,6 +475,12 @@ export async function parseArguments(
           description: 'Path to a file with fake model responses for testing.',
           hidden: true,
         })
+        .option('fake-responses-non-strict', {
+          type: 'string',
+          description:
+            'Path to a file with fake model responses for testing (non-strict mode).',
+          hidden: true,
+        })
         .option('record-responses', {
           type: 'string',
           description: 'Path to a file to record model responses for testing.',
@@ -1074,6 +1081,7 @@ export async function loadCliConfig(
     gemmaModelRouter: settings.experimental?.gemmaModelRouter,
     adk: settings.experimental?.adk,
     fakeResponses: argv.fakeResponses,
+    fakeResponsesNonStrict: argv.fakeResponsesNonStrict,
     recordResponses: argv.recordResponses,
     retryFetchErrors: settings.general?.retryFetchErrors,
     billing: settings.billing,

packages/cli/src/ui/commands/rewindCommand.tsx

@@ -14,7 +14,6 @@ import { type HistoryItem } from '../types.js';
 import { convertSessionToHistoryFormats } from '../hooks/useSessionBrowser.js';
 import { revertFileChanges } from '../utils/rewindFileOps.js';
 import { RewindOutcome } from '../components/RewindConfirmation.js';
-import type { Content } from '@google/genai';
 import {
   checkExhaustive,
   coreEvents,
@@ -58,7 +57,7 @@ async function rewindConversation(
     const { uiHistory } = convertSessionToHistoryFormats(conversation.messages);
     const clientHistory = convertSessionToClientHistory(conversation.messages);
 
-    client.setHistory(clientHistory as Content[]);
+    client.setHistory(clientHistory);
 
     // Reset context manager as we are rewinding history
     await context.services.agentContext?.config

packages/cli/src/ui/hooks/useSessionBrowser.test.ts

@@ -194,14 +194,16 @@ describe('convertSessionToHistoryFormats', () => {
 
     const clientHistory = convertSessionToClientHistory(messages);
     expect(clientHistory).toHaveLength(2);
-    expect(clientHistory[0]).toEqual({
-      role: 'user',
-      parts: [{ text: 'Hello' }],
-    });
-    expect(clientHistory[1]).toEqual({
-      role: 'model',
-      parts: [{ text: 'Hi there' }],
-    });
+    expect(clientHistory.map((h) => h.content)).toEqual([
+      {
+        role: 'user',
+        parts: [{ text: 'Hello' }],
+      },
+      {
+        role: 'model',
+        parts: [{ text: 'Hi there' }],
+      },
+    ]);
   });
 
   it('should convert thinking tokens (thoughts) to thinking history items', () => {
@@ -254,10 +256,12 @@ describe('convertSessionToHistoryFormats', () => {
 
     const clientHistory = convertSessionToClientHistory(messages);
     expect(clientHistory).toHaveLength(1);
-    expect(clientHistory[0]).toEqual({
-      role: 'user',
-      parts: [{ text: 'Expanded content' }],
-    });
+    expect(clientHistory.map((h) => h.content)).toEqual([
+      {
+        role: 'user',
+        parts: [{ text: 'Expanded content' }],
+      },
+    ]);
   });
 
   it('should filter out slash commands from client history but keep in UI', () => {
@@ -316,33 +320,35 @@ describe('convertSessionToHistoryFormats', () => {
 
     const clientHistory = convertSessionToClientHistory(messages);
     expect(clientHistory).toHaveLength(3); // User, Model (call), User (response)
-    expect(clientHistory[0]).toEqual({
-      role: 'user',
-      parts: [{ text: 'What time is it?' }],
-    });
-    expect(clientHistory[1]).toEqual({
-      role: 'model',
-      parts: [
-        {
-          functionCall: {
-            name: 'get_time',
-            args: {},
-            id: 'call_1',
+    expect(clientHistory.map((h) => h.content)).toEqual([
+      {
+        role: 'user',
+        parts: [{ text: 'What time is it?' }],
+      },
+      {
+        role: 'model',
+        parts: [
+          {
+            functionCall: {
+              name: 'get_time',
+              args: {},
+              id: 'call_1',
+            },
           },
-        },
-      ],
-    });
-    expect(clientHistory[2]).toEqual({
-      role: 'user',
-      parts: [
-        {
-          functionResponse: {
-            id: 'call_1',
-            name: 'get_time',
-            response: { output: '12:00' },
+        ],
+      },
+      {
+        role: 'user',
+        parts: [
+          {
+            functionResponse: {
+              name: 'get_time',
+              response: { output: '12:00' },
+              id: 'call_1',
+            },
           },
-        },
-      ],
-    });
+        ],
+      },
+    ]);
   });
 });

packages/cli/src/ui/hooks/useSessionBrowser.ts

@@ -12,22 +12,28 @@ import {
   convertSessionToClientHistory,
   uiTelemetryService,
   loadConversationRecord,
-  type Config,
-  type ResumedSessionData,
+} from '@google/gemini-cli-core';
+import type {
+  HistoryTurn,
+  Config,
+  ResumedSessionData,
 } from '@google/gemini-cli-core';
 import {
   convertSessionToHistoryFormats,
   type SessionInfo,
 } from '../../utils/sessionUtils.js';
-import type { Part } from '@google/genai';
 
 export { convertSessionToHistoryFormats };
 
+import type { Part } from '@google/genai';
+
 export const useSessionBrowser = (
   config: Config,
   onLoadHistory: (
     uiHistory: HistoryItemWithoutId[],
-    clientHistory: Array<{ role: 'user' | 'model'; parts: Part[] }>,
+    clientHistory: Array<
+      { role: 'user' | 'model'; parts: Part[] } | HistoryTurn
+    >,
     resumedSessionData: ResumedSessionData,
   ) => Promise<void>,
 ) => {

packages/cli/src/ui/hooks/useSessionResume.test.ts

@@ -13,6 +13,7 @@ import type {
   ResumedSessionData,
   ConversationRecord,
   MessageRecord,
+  HistoryTurn,
 } from '@google/gemini-cli-core';
 import type { UseHistoryManagerReturn } from './useHistoryManager.js';
 import type { HistoryItemWithoutId } from '../types.js';
@@ -527,10 +528,12 @@ describe('useSessionResume', () => {
 
       // Should only have the non-slash-command message
       expect(clientHistory).toHaveLength(1);
-      expect(clientHistory[0]).toEqual({
-        role: 'user',
-        parts: [{ text: 'Regular message' }],
-      });
+      expect(clientHistory.map((h: HistoryTurn) => h.content)).toEqual([
+        {
+          role: 'user',
+          parts: [{ text: 'Regular message' }],
+        },
+      ]);
 
       // But UI history should have both
       expect(mockHistoryManager.addItem).toHaveBeenCalledTimes(2);

packages/cli/src/ui/hooks/useSessionResume.ts

@@ -7,14 +7,17 @@
 import { useCallback, useEffect, useRef, useState } from 'react';
 import {
   coreEvents,
-  type Config,
-  type ResumedSessionData,
   convertSessionToClientHistory,
 } from '@google/gemini-cli-core';
-import type { Part } from '@google/genai';
+import type {
+  HistoryTurn,
+  Config,
+  ResumedSessionData,
+} from '@google/gemini-cli-core';
 import type { HistoryItemWithoutId } from '../types.js';
 import type { UseHistoryManagerReturn } from './useHistoryManager.js';
 import { convertSessionToHistoryFormats } from './useSessionBrowser.js';
+import type { Part } from '@google/genai';
 
 interface UseSessionResumeParams {
   config: Config;
@@ -54,7 +57,9 @@ export function useSessionResume({
   const loadHistoryForResume = useCallback(
     async (
       uiHistory: HistoryItemWithoutId[],
-      clientHistory: Array<{ role: 'user' | 'model'; parts: Part[] }>,
+      clientHistory: Array<
+        { role: 'user' | 'model'; parts: Part[] } | HistoryTurn
+      >,
       resumedData: ResumedSessionData,
     ) => {
       // Wait for the client.