Revert "fix: prevent UI flicker and enable resumption after task cancellation" (#9032)

src/core/task/Task.ts

@@ -737,8 +737,7 @@ export class Task extends EventEmitter<TaskEvents> implements TaskLike {
 		// deallocated. (Although we set Cline = undefined in provider, that
 		// simply removes the reference to this instance, but the instance is
 		// still alive until this promise resolves or rejects.)
-		// Exception: Allow resume asks even when aborted for soft-interrupt UX
-		if (this.abort && type !== "resume_task" && type !== "resume_completed_task") {
+		if (this.abort) {
 			throw new Error(`[RooCode#ask] task ${this.taskId}.${this.instanceId} aborted`)
 		}
 
@@ -1256,7 +1255,7 @@ export class Task extends EventEmitter<TaskEvents> implements TaskLike {
 		])
 	}
 
-	public async resumeTaskFromHistory() {
+	private async resumeTaskFromHistory() {
 		if (this.enableBridge) {
 			try {
 				await BridgeOrchestrator.subscribeToTask(this)
@@ -1348,13 +1347,6 @@ export class Task extends EventEmitter<TaskEvents> implements TaskLike {
 
 		const { response, text, images } = await this.ask(askType) // Calls `postStateToWebview`.
 
-		// Reset abort flags AFTER user responds to resume ask.
-		// This is critical for the cancel → resume flow: when a task is soft-aborted
-		// (abandoned = false), we keep the instance alive but set abort = true.
-		// We only clear these flags after the user confirms they want to resume,
-		// preventing the old stream from continuing if abort was set.
-		this.resetAbortAndStreamingState()
-
 		let responseText: string | undefined
 		let responseImages: string[] | undefined
 
@@ -1533,86 +1525,6 @@ export class Task extends EventEmitter<TaskEvents> implements TaskLike {
 		await this.initiateTaskLoop(newUserContent)
 	}
 
-	/**
-	 * Resets abort flags and streaming state to allow task resumption.
-	 * Centralizes the state reset logic used after user confirms task resumption.
-	 *
-	 * @private
-	 */
-	private resetAbortAndStreamingState(): void {
-		this.abort = false
-		this.abandoned = false
-		this.abortReason = undefined
-		this.didFinishAbortingStream = false
-		this.isStreaming = false
-
-		// Reset streaming-local fields to avoid stale state from previous stream
-		this.currentStreamingContentIndex = 0
-		this.currentStreamingDidCheckpoint = false
-		this.assistantMessageContent = []
-		this.didCompleteReadingStream = false
-		this.userMessageContent = []
-		this.userMessageContentReady = false
-		this.didRejectTool = false
-		this.didAlreadyUseTool = false
-		this.presentAssistantMessageLocked = false
-		this.presentAssistantMessageHasPendingUpdates = false
-		this.assistantMessageParser.reset()
-	}
-
-	/**
-	 * Present a resumable ask on an aborted task without rehydrating.
-	 * Used by soft-interrupt (cancelTask) to show Resume/Terminate UI.
-	 * Selects the appropriate ask type based on the last relevant message.
-	 * If the user clicks Resume, resets abort flags and continues the task loop.
-	 */
-	public async presentResumableAsk(): Promise<void> {
-		const lastClineMessage = this.clineMessages
-			.slice()
-			.reverse()
-			.find((m) => !(m.ask === "resume_task" || m.ask === "resume_completed_task"))
-
-		let askType: ClineAsk
-		if (lastClineMessage?.ask === "completion_result") {
-			askType = "resume_completed_task"
-		} else {
-			askType = "resume_task"
-		}
-
-		const { response, text, images } = await this.ask(askType)
-
-		// If user clicked Resume (not Terminate), reset abort flags and continue
-		if (response === "yesButtonClicked" || response === "messageResponse") {
-			// Reset abort flags to allow the loop to continue
-			this.resetAbortAndStreamingState()
-
-			// Prepare content for resuming the task loop
-			let userContent: Anthropic.Messages.ContentBlockParam[] = []
-
-			if (response === "messageResponse" && text) {
-				// User provided additional instructions
-				await this.say("user_feedback", text, images)
-				userContent.push({
-					type: "text",
-					text: `\n\nNew instructions for task continuation:\n<user_message>\n${text}\n</user_message>`,
-				})
-				if (images && images.length > 0) {
-					userContent.push(...formatResponse.imageBlocks(images))
-				}
-			} else {
-				// Simple resume with no new instructions
-				userContent.push({
-					type: "text",
-					text: "[TASK RESUMPTION] Resuming task...",
-				})
-			}
-
-			// Continue the task loop
-			await this.initiateTaskLoop(userContent)
-		}
-		// If user clicked Terminate (noButtonClicked), do nothing - task stays aborted
-	}
-
 	public async abortTask(isAbandoned = false) {
 		// Aborting task
 
@@ -1624,17 +1536,12 @@ export class Task extends EventEmitter<TaskEvents> implements TaskLike {
 		this.abort = true
 		this.emit(RooCodeEventName.TaskAborted)
 
-		// Only dispose if this is a hard abort (abandoned)
-		// For soft abort (user cancel), keep the instance alive so we can present a resumable ask
-		if (isAbandoned) {
-			try {
-				this.dispose() // Call the centralized dispose method
-			} catch (error) {
-				console.error(`Error during task ${this.taskId}.${this.instanceId} disposal:`, error)
-				// Don't rethrow - we want abort to always succeed
-			}
+		try {
+			this.dispose() // Call the centralized dispose method
+		} catch (error) {
+			console.error(`Error during task ${this.taskId}.${this.instanceId} disposal:`, error)
+			// Don't rethrow - we want abort to always succeed
 		}
-
 		// Save the countdown message in the automatic retry or other content.
 		try {
 			// Save the countdown message in the automatic retry or other content.

src/core/task/__tests__/Task.presentResumableAsk.abort-reset.spec.ts

@@ -1,146 +0,0 @@
-import { describe, it, expect, vi, beforeEach, afterEach } from "vitest"
-import { ProviderSettings } from "@roo-code/types"
-
-import { Task } from "../Task"
-import { ClineProvider } from "../../webview/ClineProvider"
-
-// Mocks similar to Task.dispose.test.ts
-vi.mock("../../webview/ClineProvider")
-vi.mock("../../../integrations/terminal/TerminalRegistry", () => ({
-	TerminalRegistry: {
-		releaseTerminalsForTask: vi.fn(),
-	},
-}))
-vi.mock("../../ignore/RooIgnoreController")
-vi.mock("../../protect/RooProtectedController")
-vi.mock("../../context-tracking/FileContextTracker")
-vi.mock("../../../services/browser/UrlContentFetcher")
-vi.mock("../../../services/browser/BrowserSession")
-vi.mock("../../../integrations/editor/DiffViewProvider")
-vi.mock("../../tools/ToolRepetitionDetector")
-vi.mock("../../../api", () => ({
-	buildApiHandler: vi.fn(() => ({
-		getModel: () => ({ info: {}, id: "test-model" }),
-	})),
-}))
-vi.mock("../AutoApprovalHandler")
-
-// Mock TelemetryService
-vi.mock("@roo-code/telemetry", () => ({
-	TelemetryService: {
-		instance: {
-			captureTaskCreated: vi.fn(),
-			captureTaskRestarted: vi.fn(),
-			captureConversationMessage: vi.fn(),
-		},
-	},
-}))
-
-describe("Task.presentResumableAsk abort reset", () => {
-	let mockProvider: any
-	let mockApiConfiguration: ProviderSettings
-	let task: Task
-
-	beforeEach(() => {
-		vi.clearAllMocks()
-
-		mockProvider = {
-			context: {
-				globalStorageUri: { fsPath: "/test/path" },
-			},
-			getState: vi.fn().mockResolvedValue({ mode: "code" }),
-			postStateToWebview: vi.fn().mockResolvedValue(undefined),
-			postMessageToWebview: vi.fn().mockResolvedValue(undefined),
-			updateTaskHistory: vi.fn().mockResolvedValue(undefined),
-			log: vi.fn(),
-		}
-
-		mockApiConfiguration = {
-			apiProvider: "anthropic",
-			apiKey: "test-key",
-		} as ProviderSettings
-
-		task = new Task({
-			provider: mockProvider as ClineProvider,
-			apiConfiguration: mockApiConfiguration,
-			startTask: false,
-		})
-	})
-
-	afterEach(() => {
-		// Ensure we don't leave event listeners dangling
-		task.dispose()
-	})
-
-	it("resets abort flags and continues the loop on yesButtonClicked", async () => {
-		// Arrange aborted state
-		task.abort = true
-		task.abortReason = "user_cancelled"
-		task.didFinishAbortingStream = true
-		task.isStreaming = true
-
-		// minimal message history
-		task.clineMessages = [{ ts: Date.now() - 1000, type: "say", say: "text", text: "prev" } as any]
-
-		// Spy and stub ask + loop
-		const askSpy = vi.spyOn(task as any, "ask").mockResolvedValue({ response: "yesButtonClicked" })
-		const loopSpy = vi.spyOn(task as any, "initiateTaskLoop").mockResolvedValue(undefined)
-
-		// Act
-		await task.presentResumableAsk()
-
-		// Assert ask was presented
-		expect(askSpy).toHaveBeenCalled()
-
-		// Abort flags cleared
-		expect(task.abort).toBe(false)
-		expect(task.abandoned).toBe(false)
-		expect(task.abortReason).toBeUndefined()
-		expect(task.didFinishAbortingStream).toBe(false)
-		expect(task.isStreaming).toBe(false)
-
-		// Streaming-local state cleared
-		expect(task.currentStreamingContentIndex).toBe(0)
-		expect(task.assistantMessageContent).toEqual([])
-		expect(task.userMessageContentReady).toBe(false)
-		expect(task.didRejectTool).toBe(false)
-		expect(task.presentAssistantMessageLocked).toBe(false)
-
-		// Loop resumed
-		expect(loopSpy).toHaveBeenCalledTimes(1)
-	})
-
-	it("includes user feedback when resuming with messageResponse", async () => {
-		task.abort = true
-		task.clineMessages = [{ ts: Date.now() - 1000, type: "say", say: "text", text: "prev" } as any]
-
-		const askSpy = vi
-			.spyOn(task as any, "ask")
-			.mockResolvedValue({ response: "messageResponse", text: "Continue with this", images: undefined })
-		const saySpy = vi.spyOn(task, "say").mockResolvedValue(undefined as any)
-		const loopSpy = vi.spyOn(task as any, "initiateTaskLoop").mockResolvedValue(undefined)
-
-		await task.presentResumableAsk()
-
-		expect(askSpy).toHaveBeenCalled()
-		expect(saySpy).toHaveBeenCalledWith("user_feedback", "Continue with this", undefined)
-		expect(loopSpy).toHaveBeenCalledTimes(1)
-	})
-
-	it("does nothing when user clicks Terminate (noButtonClicked)", async () => {
-		task.abort = true
-		task.abortReason = "user_cancelled"
-		task.clineMessages = [{ ts: Date.now() - 1000, type: "say", say: "text", text: "prev" } as any]
-
-		vi.spyOn(task as any, "ask").mockResolvedValue({ response: "noButtonClicked" })
-		const loopSpy = vi.spyOn(task as any, "initiateTaskLoop").mockResolvedValue(undefined)
-
-		await task.presentResumableAsk()
-
-		// Still aborted
-		expect(task.abort).toBe(true)
-		expect(task.abortReason).toBe("user_cancelled")
-		// No loop resume
-		expect(loopSpy).not.toHaveBeenCalled()
-	})
-})

src/core/task/__tests__/Task.spec.ts

@@ -1722,12 +1722,12 @@ describe("Cline", () => {
 			// Mock the dispose method to track cleanup
 			const disposeSpy = vi.spyOn(task, "dispose").mockImplementation(() => {})
 
-			// Call abortTask (soft cancel - same path as UI Cancel button)
+			// Call abortTask
 			await task.abortTask()
 
-			// Verify the same behavior as Cancel button: soft abort sets abort flag but does not dispose
+			// Verify the same behavior as Cancel button
 			expect(task.abort).toBe(true)
-			expect(disposeSpy).not.toHaveBeenCalled()
+			expect(disposeSpy).toHaveBeenCalled()
 		})
 
 		it("should work with TaskLike interface", async () => {
@@ -1771,8 +1771,8 @@ describe("Cline", () => {
 			// Spy on console.error to verify error is logged
 			const consoleErrorSpy = vi.spyOn(console, "error").mockImplementation(() => {})
 
-			// abortTask should not throw even if dispose fails (hard abort triggers dispose)
-			await expect(task.abortTask(true)).resolves.not.toThrow()
+			// abortTask should not throw even if dispose fails
+			await expect(task.abortTask()).resolves.not.toThrow()
 
 			// Verify error was logged
 			expect(consoleErrorSpy).toHaveBeenCalledWith(expect.stringContaining("Error during task"), mockError)

src/core/webview/ClineProvider.ts

@@ -50,7 +50,6 @@ import { Package } from "../../shared/package"
 import { findLast } from "../../shared/array"
 import { supportPrompt } from "../../shared/support-prompt"
 import { GlobalFileNames } from "../../shared/globalFileNames"
-import { safeJsonParse } from "../../shared/safeJsonParse"
 import type { ExtensionMessage, ExtensionState, MarketplaceInstalledMetadata } from "../../shared/ExtensionMessage"
 import { Mode, defaultModeSlug, getModeBySlug } from "../../shared/modes"
 import { experimentDefault } from "../../shared/experiments"
@@ -145,10 +144,6 @@ export class ClineProvider
 	private pendingOperations: Map<string, PendingEditOperation> = new Map()
 	private static readonly PENDING_OPERATION_TIMEOUT_MS = 30000 // 30 seconds
 
-	// Transactional state posting
-	private uiUpdatePaused: boolean = false
-	private pendingState: ExtensionState | null = null
-
 	public isViewLaunched = false
 	public settingsImportedAt?: number
 	public readonly latestAnnouncementId = "nov-2025-v3.30.0-pr-fixer" // v3.30.0 PR Fixer announcement
@@ -1629,26 +1624,8 @@ export class ClineProvider
 		await this.postStateToWebview()
 	}
 
-	public beginStateTransaction(): void {
-		this.uiUpdatePaused = true
-	}
-
-	public async endStateTransaction(): Promise<void> {
-		this.uiUpdatePaused = false
-		if (this.pendingState) {
-			await this.view?.webview.postMessage({ type: "state", state: this.pendingState })
-			this.pendingState = null
-		}
-	}
-
 	async postStateToWebview() {
 		const state = await this.getStateToPostToWebview()
-
-		if (this.uiUpdatePaused) {
-			this.pendingState = state
-			return
-		}
-
 		this.postMessageToWebview({ type: "state", state })
 
 		// Check MDM compliance and send user to account tab if not compliant
@@ -2640,13 +2617,24 @@ export class ClineProvider
 
 		console.log(`[cancelTask] cancelling task ${task.taskId}.${task.instanceId}`)
 
-		// Mark this as a user-initiated cancellation
+		const { historyItem, uiMessagesFilePath } = await this.getTaskWithId(task.taskId)
+
+		// Preserve parent and root task information for history item.
+		const rootTask = task.rootTask
+		const parentTask = task.parentTask
+
+		// Mark this as a user-initiated cancellation so provider-only rehydration can occur
 		task.abortReason = "user_cancelled"
 
-		// Soft abort (isAbandoned = false) to keep the instance alive
-		await task.abortTask(false)
+		// Capture the current instance to detect if rehydrate already occurred elsewhere
+		const originalInstanceId = task.instanceId
+
+		// Begin abort (non-blocking)
+		task.abortTask()
+
+		// Immediately mark the original instance as abandoned to prevent any residual activity
+		task.abandoned = true
 
-		// Wait for abort to complete
 		await pWaitFor(
 			() =>
 				this.getCurrentTask()! === undefined ||
@@ -2663,52 +2651,28 @@ export class ClineProvider
 			console.error("Failed to abort task")
 		})
 
-		// Deterministic spinner stop: If the last api_req_started has no cost and no cancelReason,
-		// inject cancelReason to stop the spinner
-		try {
-			let lastApiReqStartedIndex = -1
-			for (let i = task.clineMessages.length - 1; i >= 0; i--) {
-				if (task.clineMessages[i].type === "say" && task.clineMessages[i].say === "api_req_started") {
-					lastApiReqStartedIndex = i
-					break
-				}
-			}
+		// Defensive safeguard: if current instance already changed, skip rehydrate
+		const current = this.getCurrentTask()
+		if (current && current.instanceId !== originalInstanceId) {
+			this.log(
+				`[cancelTask] Skipping rehydrate: current instance ${current.instanceId} != original ${originalInstanceId}`,
+			)
+			return
+		}
 
-			if (lastApiReqStartedIndex !== -1) {
-				const lastApiReqStarted = task.clineMessages[lastApiReqStartedIndex]
-				const apiReqInfo = safeJsonParse<{ cost?: number; cancelReason?: string }>(
-					lastApiReqStarted.text || "{}",
-					{},
+		// Final race check before rehydrate to avoid duplicate rehydration
+		{
+			const currentAfterCheck = this.getCurrentTask()
+			if (currentAfterCheck && currentAfterCheck.instanceId !== originalInstanceId) {
+				this.log(
+					`[cancelTask] Skipping rehydrate after final check: current instance ${currentAfterCheck.instanceId} != original ${originalInstanceId}`,
 				)
-
-				if (apiReqInfo && apiReqInfo.cost === undefined && apiReqInfo.cancelReason === undefined) {
-					apiReqInfo.cancelReason = "user_cancelled"
-					lastApiReqStarted.text = JSON.stringify(apiReqInfo)
-					await task.overwriteClineMessages([...task.clineMessages])
-					console.log(`[cancelTask] Injected cancelReason for deterministic spinner stop`)
-				}
+				return
 			}
-		} catch (error) {
-			console.error(`[cancelTask] Failed to inject cancelReason:`, error)
 		}
 
-		// Update UI immediately to reflect current state
-		await this.postStateToWebview()
-
-		// Schedule non-blocking resumption to present "Resume Task" ask
-		// Use setImmediate to avoid blocking the webview handler
-		setImmediate(() => {
-			if (task && !task.abandoned) {
-				// Present a resume ask without rehydrating - just show the Resume/Terminate UI
-				task.presentResumableAsk().catch((error) => {
-					console.error(
-						`[cancelTask] Failed to present resume ask: ${
-							error instanceof Error ? error.message : String(error)
-						}`,
-					)
-				})
-			}
-		})
+		// Clears task again, so we need to abortTask manually above.
+		await this.createTaskWithHistoryItem({ ...historyItem, rootTask, parentTask })
 	}
 
 	// Clear the current task without treating it as a subtask.

src/core/webview/__tests__/ClineProvider.cancelTask.present-ask.spec.ts

@@ -1,60 +0,0 @@
-import { describe, it, expect, vi, beforeEach, afterEach } from "vitest"
-import { ClineProvider } from "../ClineProvider"
-
-describe("ClineProvider.cancelTask - schedules presentResumableAsk", () => {
-	let provider: ClineProvider
-	let mockTask: any
-
-	beforeEach(() => {
-		vi.useFakeTimers()
-		// Create a bare instance without running constructor
-		provider = Object.create(ClineProvider.prototype) as ClineProvider
-
-		mockTask = {
-			taskId: "task-1",
-			instanceId: "inst-1",
-			abortReason: undefined,
-			abandoned: false,
-			abortTask: vi.fn().mockResolvedValue(undefined),
-			isStreaming: false,
-			didFinishAbortingStream: true,
-			isWaitingForFirstChunk: false,
-			// Last api_req_started without cost/cancelReason so provider injects cancelReason
-			clineMessages: [
-				{ ts: Date.now() - 2000, type: "say", say: "text", text: "hello" },
-				{ ts: Date.now() - 1000, type: "say", say: "api_req_started", text: JSON.stringify({}) },
-			],
-			overwriteClineMessages: vi.fn().mockResolvedValue(undefined),
-			presentResumableAsk: vi.fn().mockResolvedValue(undefined),
-		}
-
-		// Patch required instance methods used by cancelTask
-		;(provider as any).getCurrentTask = vi.fn().mockReturnValue(mockTask)
-		;(provider as any).postStateToWebview = vi.fn().mockResolvedValue(undefined)
-	})
-
-	afterEach(() => {
-		vi.useRealTimers()
-	})
-
-	it("injects cancelReason and schedules presentResumableAsk on soft cancel", async () => {
-		// Act
-		await (provider as any).cancelTask()
-
-		// Assert that abort was initiated
-		expect(mockTask.abortTask).toHaveBeenCalledWith(false)
-
-		// cancelReason injected for spinner stop
-		const last = mockTask.clineMessages.at(-1)
-		expect(last.say).toBe("api_req_started")
-		const parsed = JSON.parse(last.text || "{}")
-		expect(parsed.cancelReason).toBe("user_cancelled")
-
-		// presentResumableAsk is scheduled via setImmediate
-		expect(mockTask.presentResumableAsk).not.toHaveBeenCalled()
-		vi.runAllTimers()
-		// run microtasks as well to flush any pending promises in the scheduled callback
-		await Promise.resolve()
-		expect(mockTask.presentResumableAsk).toHaveBeenCalledTimes(1)
-	})
-})

src/core/webview/webviewMessageHandler.ts

@@ -1033,26 +1033,18 @@ export const webviewMessageHandler = async (
 			const result = checkoutRestorePayloadSchema.safeParse(message.payload)
 
 			if (result.success) {
-				// Begin transaction to buffer state updates
-				provider.beginStateTransaction()
+				await provider.cancelTask()
 
 				try {
-					await provider.cancelTask()
-
-					try {
-						await pWaitFor(() => provider.getCurrentTask()?.isInitialized === true, { timeout: 3_000 })
-					} catch (error) {
-						vscode.window.showErrorMessage(t("common:errors.checkpoint_timeout"))
-					}
+					await pWaitFor(() => provider.getCurrentTask()?.isInitialized === true, { timeout: 3_000 })
+				} catch (error) {
+					vscode.window.showErrorMessage(t("common:errors.checkpoint_timeout"))
+				}
 
-					try {
-						await provider.getCurrentTask()?.checkpointRestore(result.data)
-					} catch (error) {
-						vscode.window.showErrorMessage(t("common:errors.checkpoint_failed"))
-					}
-				} finally {
-					// End transaction and post consolidated state
-					await provider.endStateTransaction()
+				try {
+					await provider.getCurrentTask()?.checkpointRestore(result.data)
+				} catch (error) {
+					vscode.window.showErrorMessage(t("common:errors.checkpoint_failed"))
 				}
 			}
 

webview-ui/src/components/chat/ChatView.tsx

@@ -58,7 +58,6 @@ import { QueuedMessages } from "./QueuedMessages"
 import DismissibleUpsell from "../common/DismissibleUpsell"
 import { useCloudUpsell } from "@src/hooks/useCloudUpsell"
 import { Cloud } from "lucide-react"
-import { safeJsonParse } from "../../../../src/shared/safeJsonParse"
 
 export interface ChatViewProps {
 	isHidden: boolean
@@ -548,21 +547,10 @@ const ChatViewComponent: React.ForwardRefRenderFunction<ChatViewRef, ChatViewPro
 				lastApiReqStarted.text !== undefined &&
 				lastApiReqStarted.say === "api_req_started"
 			) {
-				const info = safeJsonParse(lastApiReqStarted.text)
+				const cost = JSON.parse(lastApiReqStarted.text).cost
 
-				// If cancelReason is defined, the stream has been cancelled (terminal state)
-				if (typeof info === "object" && info !== null) {
-					if ("cancelReason" in info && info.cancelReason !== undefined) {
-						return false
-					}
-
-					// Otherwise, check if cost is defined to determine if streaming is complete
-					if ("cost" in info && info.cost !== undefined) {
-						return false // API request has finished.
-					}
-
-					// If we have api_req_started without cost or cancelReason, streaming is in progress
-					return true
+				if (cost === undefined) {
+					return true // API request has not finished yet.
 				}
 			}
 		}