fix: address PR review feedback for task cancellation

- Add proper resource disposal in resetToResumableState() to prevent memory leaks
- Add JSDoc documentation for skipSave parameter in abortTask()
- Add error handling for resetToResumableState() and ask() operations
- Extract resumption logic into dedicated handleUserCancellationResume() method
- Add 30-second timeout safety net for cancellation in ClineProvider

These changes ensure proper cleanup of resources (browsers, terminals) during
task cancellation while maintaining the no-rerender behavior.

Author: daniel-lxs

src/core/task/Task.ts

@@ -1489,7 +1489,13 @@ export class Task extends EventEmitter<TaskEvents> implements TaskLike {
 		}
 	}
 
-public async abortTask(isAbandoned = false, skipSave = false) {
+/**
+	 * Aborts the current task and optionally saves messages.
+	 *
+	 * @param isAbandoned - If true, marks the task as abandoned (no cleanup needed)
+	 * @param skipSave - If true, skips saving messages (used during user cancellation when messages are already saved)
+	 */
+	public async abortTask(isAbandoned = false, skipSave = false) {
 		console.log(`[subtasks] aborting task ${this.taskId}.${this.instanceId}`)
 
 		// Will stop any autonomously running promises.
@@ -1521,6 +1527,9 @@ public async abortTask(isAbandoned = false, skipSave = false) {
 	/**
 	 * Reset the task to a resumable state without recreating the instance.
 	 * This is used when canceling a task to avoid unnecessary rerenders.
+	 *
+	 * IMPORTANT: This method cleans up resources to prevent memory leaks
+	 * while preserving the task instance for resumption.
 	 */
 	public async resetToResumableState() {
 		console.log(`[subtasks] resetting task ${this.taskId}.${this.instanceId} to resumable state`)
@@ -1553,7 +1562,6 @@ public async abortTask(isAbandoned = false, skipSave = false) {
 		this.askResponse = undefined
 		this.askResponseText = undefined
 		this.askResponseImages = undefined
-		this.blockingAsk = undefined
 
 		// Reset parser if exists
 		if (this.assistantMessageParser) {
@@ -1566,9 +1574,27 @@ public async abortTask(isAbandoned = false, skipSave = false) {
 			await this.diffViewProvider.reset()
 		}
 
-		// The task is now ready to be resumed
-		// The API request status has already been updated by abortStream
-		// We don't add the resume_task message here because ask() will add it
+		// Dispose of resources that could accumulate if tasks are repeatedly cancelled
+		// These will be recreated as needed when the task resumes
+		try {
+			// Close browser sessions to free memory and browser processes
+			if (this.urlContentFetcher) {
+				this.urlContentFetcher.closeBrowser()
+			}
+			if (this.browserSession) {
+				this.browserSession.closeBrowser()
+			}
+
+			// Release any terminals associated with this task
+			// They will be recreated if needed when the task resumes
+			if (this.terminalProcess) {
+				this.terminalProcess.abort()
+				this.terminalProcess = undefined
+			}
+		} catch (error) {
+			console.error(`Error disposing resources during resetToResumableState: ${error}`)
+			// Continue even if resource cleanup fails
+		}
 
 		// Keep messages and history intact for resumption
 		// The task is now ready to be resumed without recreation
@@ -2771,6 +2797,45 @@ if (this.abort) {
 		}
 	}
 
+	/**
+	 * Handles the resumption flow after a user cancels a task.
+	 * This method resets the task state, shows the resume prompt,
+	 * and continues with new user input if provided.
+	 *
+	 * @returns Promise<boolean> - true if the task should end, false to continue
+	 */
+	private async handleUserCancellationResume(): Promise<boolean> {
+		try {
+			// Reset the task to a resumable state
+			this.abort = false
+			await this.resetToResumableState()
+
+			// Show the resume prompt
+			const { response, text, images } = await this.ask("resume_task")
+
+			if (response === "messageResponse") {
+				await this.say("user_feedback", text, images)
+				// Continue with the new user input
+				const newUserContent: Anthropic.Messages.ContentBlockParam[] = []
+				if (text) {
+					newUserContent.push({ type: "text", text })
+				}
+				if (images && images.length > 0) {
+					newUserContent.push(...formatResponse.imageBlocks(images))
+				}
+				// Recursively continue with the new content
+				return await this.recursivelyMakeClineRequests(newUserContent)
+			}
+			// If not messageResponse, the task will end
+			return true
+		} catch (error) {
+			// If there's an error during resumption, log it and end the task
+			console.error(`Error during user cancellation resume: ${error}`)
+			// Re-throw to maintain existing error handling behavior
+			throw error
+		}
+	}
+
 	// Getters
 
 	public get cwd() {

src/core/webview/ClineProvider.ts

@@ -1282,8 +1282,27 @@ export class ClineProvider
 		// Just set the abort flag - the task will handle its own resumption
 		cline.abort = true
 
+		// Add a timeout safety net to ensure the task doesn't hang indefinitely
+		// If the task doesn't respond to cancellation within 30 seconds, force abort it
+		const timeoutMs = 30000 // 30 seconds
+		const timeoutPromise = new Promise<void>((resolve) => {
+			setTimeout(async () => {
+				// Check if the task is still in an aborted state
+				if (cline.abort && !cline.abandoned) {
+					console.log(
+						`[subtasks] task ${cline.taskId}.${cline.instanceId} did not respond to cancellation within ${timeoutMs}ms, forcing abort`,
+					)
+					// Force abandon the task to ensure cleanup
+					cline.abandoned = true
+					// Remove it from the stack
+					await this.removeClineFromStack()
+					resolve()
+				}
+			}, timeoutMs)
+		})
+
 		// The task's streaming loop will detect the abort flag and handle the resumption
-		// No need to wait or do anything else here
+		// The timeout ensures we don't wait indefinitely
 	}
 
 	async updateCustomInstructions(instructions?: string) {