feat(cli): add --delete flag to /exit command for session deletion (#19332)

Co-authored-by: David Pierce <davidapierce@google.com>

packages/cli/src/ui/commands/quitCommand.test.ts

@@ -33,11 +33,12 @@ describe('quitCommand', () => {
     });
 
     if (!quitCommand.action) throw new Error('Action is not defined');
-    const result = quitCommand.action(mockContext, 'quit');
+    const result = quitCommand.action(mockContext, '');
 
     expect(formatDuration).toHaveBeenCalledWith(3600000); // 1 hour in ms
     expect(result).toEqual({
       type: 'quit',
+      deleteSession: false,
       messages: [
         {
           type: 'user',
@@ -52,4 +53,54 @@ describe('quitCommand', () => {
       ],
     });
   });
+
+  it('sets deleteSession to true when --delete flag is provided', () => {
+    const mockContext = createMockCommandContext({
+      session: {
+        stats: {
+          sessionStartTime: new Date('2025-01-01T00:00:00Z'),
+        },
+      },
+    });
+
+    if (!quitCommand.action) throw new Error('Action is not defined');
+    const result = quitCommand.action(mockContext, '--delete');
+
+    expect(result).toEqual({
+      type: 'quit',
+      deleteSession: true,
+      messages: [
+        {
+          type: 'user',
+          text: '/quit',
+          id: expect.any(Number),
+        },
+        {
+          type: 'quit',
+          duration: '1h 0m 0s',
+          id: expect.any(Number),
+        },
+      ],
+    });
+  });
+
+  it('does not set deleteSession for unrecognized args', () => {
+    const mockContext = createMockCommandContext({
+      session: {
+        stats: {
+          sessionStartTime: new Date('2025-01-01T00:00:00Z'),
+        },
+      },
+    });
+
+    if (!quitCommand.action) throw new Error('Action is not defined');
+    const result = quitCommand.action(mockContext, 'some-random-arg');
+
+    expect(result).toEqual(
+      expect.objectContaining({
+        type: 'quit',
+        deleteSession: false,
+      }),
+    );
+  });
 });

packages/cli/src/ui/commands/quitCommand.ts

@@ -13,13 +13,16 @@ export const quitCommand: SlashCommand = {
   description: 'Exit the cli',
   kind: CommandKind.BUILT_IN,
   autoExecute: true,
-  action: (context) => {
+  action: (context, args) => {
     const now = Date.now();
     const { sessionStartTime } = context.session.stats;
     const wallDuration = now - sessionStartTime.getTime();
 
+    const deleteSession = args.trim() === '--delete';
+
     return {
       type: 'quit',
+      deleteSession,
       messages: [
         {
           type: 'user',

packages/cli/src/ui/commands/types.ts

@@ -108,6 +108,8 @@ export interface CommandContext {
 export interface QuitActionReturn {
   type: 'quit';
   messages: HistoryItem[];
+  /** When true, the current session's history and temporary files will be deleted on exit. */
+  deleteSession?: boolean;
 }
 
 /**