fix(webview): reset prompt navigation on source change

Amp-Thread-ID: https://ampcode.com/threads/T-01a0aac1-c3f8-7220-a896-ac2dafbf72e1

Author: ampagent

webview-ui/src/components/chat/hooks/__tests__/usePromptHistory.spec.ts

@@ -0,0 +1,53 @@
+import { ClineMessage, HistoryItem } from "@roo-code/types"
+import { act, renderHook } from "@testing-library/react"
+
+import { usePromptHistory } from "../usePromptHistory"
+
+describe("usePromptHistory", () => {
+	it("resets navigation when switching to conversation history with identical prompts", () => {
+		const prompt = "Explain this code"
+		const taskHistory: HistoryItem[] = [
+			{
+				id: "task-1",
+				number: 1,
+				ts: 1,
+				task: prompt,
+				tokensIn: 0,
+				tokensOut: 0,
+				totalCost: 0,
+				workspace: "/workspace",
+			},
+		]
+		const conversationHistory: ClineMessage[] = [
+			{ ts: 2, type: "say", say: "user_feedback", text: prompt },
+		]
+		const setInputValue = vi.fn()
+
+		const { result, rerender } = renderHook(
+			({ clineMessages }: { clineMessages: ClineMessage[] | undefined }) =>
+				usePromptHistory({
+					clineMessages,
+					taskHistory,
+					cwd: "/workspace",
+					inputValue: "draft",
+					setInputValue,
+				}),
+			{ initialProps: { clineMessages: undefined } },
+		)
+
+		act(() => {
+			result.current.setHistoryIndex(0)
+			result.current.setTempInput("draft")
+		})
+
+		expect(result.current.promptHistory).toEqual([prompt])
+		expect(result.current.historyIndex).toBe(0)
+		expect(result.current.tempInput).toBe("draft")
+
+		rerender({ clineMessages: conversationHistory })
+
+		expect(result.current.promptHistory).toEqual([prompt])
+		expect(result.current.historyIndex).toBe(-1)
+		expect(result.current.tempInput).toBe("")
+	})
+})

webview-ui/src/components/chat/hooks/usePromptHistory.ts

@@ -1,5 +1,5 @@
 import { ClineMessage, HistoryItem } from "@roo-code/types"
-import { useCallback, useEffect, useMemo, useState } from "react"
+import { useCallback, useEffect, useMemo, useRef, useState } from "react"
 
 interface UsePromptHistoryProps {
 	clineMessages: ClineMessage[] | undefined
@@ -38,6 +38,8 @@ export const usePromptHistory = ({
 	const [historyIndex, setHistoryIndex] = useState(-1)
 	const [tempInput, setTempInput] = useState("")
 	const [promptHistory, setPromptHistory] = useState<string[]>([])
+	const historySource = clineMessages?.length ? "conversation" : "task"
+	const previousHistorySource = useRef(historySource)
 
 	// Initialize prompt history with hybrid approach: conversation messages if in task, otherwise task history
 	const filteredPromptHistory = useMemo(() => {
@@ -74,14 +76,18 @@ export const usePromptHistory = ({
 		const historyChanged =
 			promptHistory.length !== filteredPromptHistory.length ||
 			promptHistory.some((prompt, index) => prompt !== filteredPromptHistory[index])
+		const historySourceChanged = previousHistorySource.current !== historySource
+		previousHistorySource.current = historySource
 
-		if (!historyChanged) return
+		if (!historyChanged && !historySourceChanged) return
 
-		setPromptHistory(filteredPromptHistory)
+		if (historyChanged) {
+			setPromptHistory(filteredPromptHistory)
+		}
 		// Reset navigation state when switching between history sources
 		setHistoryIndex(-1)
 		setTempInput("")
-	}, [filteredPromptHistory, promptHistory])
+	}, [filteredPromptHistory, historySource, promptHistory])
 
 	// Reset history navigation when user types (but not when we're setting it programmatically)
 	const resetOnInputChange = useCallback(() => {