feat: Enhance apply_diff with XML for multi-file/multi-diff operations & batch UI

packages/types/src/experiment.ts

@@ -6,12 +6,7 @@ import type { Keys, Equals, AssertEqual } from "./type-fu.js"
  * ExperimentId
  */
 
-export const experimentIds = [
-	"powerSteering",
-	"marketplace",
-	"concurrentFileReads",
-	"disableCompletionCommand",
-] as const
+export const experimentIds = ["powerSteering", "concurrentFileReads", "disableCompletionCommand", "marketplace", "multiFileApplyDiff"] as const
 
 export const experimentIdsSchema = z.enum(experimentIds)
 
@@ -26,6 +21,7 @@ export const experimentsSchema = z.object({
 	marketplace: z.boolean(),
 	concurrentFileReads: z.boolean(),
 	disableCompletionCommand: z.boolean(),
+	multiFileApplyDiff: z.boolean(),
 })
 
 export type Experiments = z.infer<typeof experimentsSchema>

src/core/assistant-message/presentAssistantMessage.ts

@@ -11,7 +11,7 @@ import { fetchInstructionsTool } from "../tools/fetchInstructionsTool"
 import { listFilesTool } from "../tools/listFilesTool"
 import { getReadFileToolDescription, readFileTool } from "../tools/readFileTool"
 import { writeToFileTool } from "../tools/writeToFileTool"
-import { applyDiffTool } from "../tools/applyDiffTool"
+import { applyDiffTool } from "../tools/multiApplyDiffTool"
 import { insertContentTool } from "../tools/insertContentTool"
 import { searchAndReplaceTool } from "../tools/searchAndReplaceTool"
 import { listCodeDefinitionNamesTool } from "../tools/listCodeDefinitionNamesTool"
@@ -31,6 +31,8 @@ import { formatResponse } from "../prompts/responses"
 import { validateToolUse } from "../tools/validateToolUse"
 import { Task } from "../task/Task"
 import { codebaseSearchTool } from "../tools/codebaseSearchTool"
+import { experiments } from "../../shared/experiments"
+import { applyDiffToolLegacy } from "../tools/applyDiffTool"
 
 /**
  * Processes and presents assistant message content to the user interface.
@@ -385,7 +387,18 @@ export async function presentAssistantMessage(cline: Task) {
 					await writeToFileTool(cline, block, askApproval, handleError, pushToolResult, removeClosingTag)
 					break
 				case "apply_diff":
-					await applyDiffTool(cline, block, askApproval, handleError, pushToolResult, removeClosingTag)
+					if (experiments.get("MULTI_FILE_APPLY_DIFF")?.enabled) {
+						await applyDiffTool(cline, block, askApproval, handleError, pushToolResult, removeClosingTag)
+					} else {
+						await applyDiffToolLegacy(
+							cline,
+							block,
+							askApproval,
+							handleError,
+							pushToolResult,
+							removeClosingTag,
+						)
+					}
 					break
 				case "insert_content":
 					await insertContentTool(cline, block, askApproval, handleError, pushToolResult, removeClosingTag)