Adding fixing save chat session overwriting (#6457)

[Linear Issue

](https://linear.app/sourcegraph/issue/QA-216/jetbrains-clicking-on-delete-button-does-nothing-in-first-attempt-for)
### Problem
Previously, whenever a user deleted a chat, disposeChat would call
clearAndRestartSession(), which in turn triggered saveSession(). This
saved the just-deleted chat back into local storage, negating the
deletion.
## Solution
Introduce a skipSave boolean to conditionally skip the
clearAndRestartSession() flow during deletion. If skipSave is true
(e.g., for a deletion), clearAndRestartSession() is not called. This
prevents the race condition of re-saving an already-deleted chat.
## Why It Works
1. Avoid Conflicts – If the user explicitly wants to remove a chat, we
no longer re-create or re-save the session.
2. Maintain Clean State – Normal operations (skipSave = false) still
clear and restart sessions. Deletions (skipSave = true) skip that path
to maintain data consistency.
3. Prevent Race Conditions – The skip logic ensures no stale data
overwrites the freshly updated local storage.


Using the skipSave flag to conditionally skip clearAndRestartSession()
is safe because:
1. During normal operations (when skipSave is false), you want to clear
and restart the session to maintain a clean state
2. During deletion (when skipSave is true), you want to skip this step
because:
The chat is being deleted anyway
clearAndRestartSession() includes a saveSession() call which could race
with the deletion


3. There's no need to create a new session when we're removing the chat
The condition helps prevent potential issues where: 
- The deletion operation is trying to remove chat history
- While simultaneously, clearAndRestartSession() might try to save the
session
- Which could lead to inconsistent state or race conditions

So yes, using the skipSave flag to conditionally skip
clearAndRestartSession() during deletion is a good practice for
maintaining data consistency.

## Test plan
Run this code in Vscode/Jetbrains debugger and delete a chat from
history



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## Changelog

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vscode/src/chat/chat-view/ChatsController.ts

@@ -446,8 +446,10 @@ export class ChatsController implements vscode.Disposable {
             return
         }
 
+        // For single chat deletion
         await chatHistory.deleteChat(authStatus, chatID)
-        this.disposeChat(chatID, true)
+        // Don't save the session when disposing after delete
+        this.disposeChat(chatID, true, { skipSave: true })
     }
 
     /**
@@ -535,7 +537,11 @@ export class ChatsController implements vscode.Disposable {
         })
     }
 
-    private disposeChat(chatID: string, includePanel: boolean): void {
+    private disposeChat(
+        chatID: string,
+        includePanel: boolean,
+        options: { skipSave?: boolean } = {}
+    ): void {
         if (chatID === this.activeEditor?.sessionID) {
             this.activeEditor = undefined
         }
@@ -549,7 +555,7 @@ export class ChatsController implements vscode.Disposable {
             removedProvider.dispose()
         }
 
-        if (includePanel && chatID === this.panel?.sessionID) {
+        if (includePanel && chatID === this.panel?.sessionID && !options.skipSave) {
             this.panel.clearAndRestartSession()
         }
     }

vscode/test/e2e/chat-history.test.ts

@@ -34,3 +34,41 @@ test.extend<ExpectedV2Events>({
     await expect(newHistoryItem).toBeVisible()
     await newHistoryItem.click()
 })
+
+test.extend<ExpectedV2Events>({
+    // list of events we expect this test to log, add to this list as needed
+    expectedV2Events: [
+        'cody.extension:installed',
+        'cody.auth.login:clicked',
+        'cody.auth.login:firstEver',
+        'cody.auth.login.token:clicked',
+        'cody.auth:connected',
+        'cody.chat-question:submitted',
+        'cody.chat-question:executed',
+        'cody.chatResponse:noCode',
+    ],
+})('delete chat from sidebar history view', async ({ page, sidebar }) => {
+    await sidebarSignin(page, sidebar)
+
+    const sidebarChat = getChatSidebarPanel(page)
+
+    const sidebarTabHistoryButton = sidebarChat.getByTestId('tab-history')
+
+    // Ensure the chat view is ready before we start typing
+    await expect(sidebarTabHistoryButton).toBeVisible()
+
+    const chatInput = getChatInputs(sidebarChat).first()
+    await chatInput.fill('Hey')
+    await chatInput.press('Enter')
+
+    await sidebarTabHistoryButton.click()
+
+    const newHistoryItem = sidebarChat.getByRole('button', { name: 'Hey' })
+    await expect(newHistoryItem).toBeVisible()
+
+    const deleteButton = sidebarChat.getByRole('button', { name: 'Delete chat' })
+    await expect(deleteButton).toBeVisible()
+    await deleteButton.click()
+
+    await expect(newHistoryItem).not.toBeVisible()
+})