refactor: streamline checkpoint handling and enhance getCheckpoints method

Author: NaccOll

src/core/assistant-message/presentAssistantMessage.ts

@@ -532,14 +532,6 @@ export async function presentAssistantMessage(cline: Task) {
 			break
 	}
 
-	const recentlyModifiedFiles = cline.fileContextTracker.getAndClearCheckpointPossibleFile()
-
-	if (recentlyModifiedFiles.length > 0) {
-		// TODO: We can track what file changes were made and only
-		// checkpoint those files, this will be save storage.
-		await checkpointSave(cline)
-	}
-
 	// Seeing out of bounds is fine, it means that the next too call is being
 	// built up and ready to add to assistantMessageContent to present.
 	// When you see the UI inactive during this, it means that a tool is

src/core/checkpoints/index.ts

@@ -298,17 +298,19 @@ export async function checkpointDiff(cline: Task, { ts, previousCommitHash, comm
 
 	TelemetryService.instance.captureCheckpointDiffed(cline.taskId)
 
-	if (!previousCommitHash && mode === "checkpoint") {
-		const previousCheckpoint = cline.clineMessages
-			.filter(({ say }) => say === "checkpoint_saved")
-			.sort((a, b) => b.ts - a.ts)
-			.find((message) => message.ts < ts)
-
-		previousCommitHash = previousCheckpoint?.text
+	let from = commitHash
+	let to: string | undefined
+
+	const checkpoints = typeof service.getCheckpoints === "function" ? service.getCheckpoints() : []
+	const idx = checkpoints.indexOf(commitHash)
+	if (idx !== -1 && idx < checkpoints.length - 1) {
+		to = checkpoints[idx + 1]
+	} else {
+		to = undefined
 	}
 
 	try {
-		const changes = await service.getDiff({ from: previousCommitHash, to: commitHash })
+		const changes = await service.getDiff({ from, to })
 
 		if (!changes?.length) {
 			vscode.window.showInformationMessage("No changes found.")

src/services/checkpoints/ShadowCheckpointService.ts

@@ -38,6 +38,10 @@ export abstract class ShadowCheckpointService extends EventEmitter {
 		return !!this.git
 	}
 
+	public getCheckpoints(): string[] {
+		return this._checkpoints.slice()
+	}
+
 	constructor(taskId: string, checkpointsDir: string, workspaceDir: string, log: (message: string) => void) {
 		super()