chore: clean checkpoint_states folder in nHistoricalStates e2e tests

.gitignore

@@ -77,3 +77,5 @@ packages/cli/.git-data.json
 dictionary.dic
 
 temp/
+
+checkpoint_states/

packages/beacon-node/src/chain/stateCache/datastore/file.ts

@@ -5,6 +5,7 @@ import {ensureDir, readFile, readFileNames, removeFile, writeIfNotExist} from ".
 import {CPStateDatastore, DatastoreKey} from "./types.js";
 
 export const CHECKPOINT_STATES_FOLDER = "./checkpoint_states";
+const CHECKPOINT_FILE_NAME_LENGTH = 82;
 
 /**
  * Implementation of CPStatePersistentApis using file system, this is beneficial for debugging.
@@ -39,7 +40,8 @@ export class FileCPStateDatastore implements CPStateDatastore {
 
   async readKeys(): Promise<DatastoreKey[]> {
     const fileNames = await readFileNames(this.folderPath);
-    // TODO: filter file names with fixed size
-    return fileNames.map((fileName) => fromHexString(fileName));
+    return fileNames
+      .filter((fileName) => fileName.startsWith("0x") && fileName.length === CHECKPOINT_FILE_NAME_LENGTH)
+      .map((fileName) => fromHexString(fileName));
   }
 }

packages/beacon-node/test/e2e/chain/stateCache/nHistoricalStates.test.ts

@@ -1,4 +1,5 @@
-import {describe, it, afterEach, expect} from "vitest";
+import fs from "node:fs";
+import {describe, it, afterEach, beforeEach, expect} from "vitest";
 import {Gauge, Histogram} from "prom-client";
 import {ChainConfig} from "@lodestar/config";
 import {Slot, phase0} from "@lodestar/types";
@@ -13,6 +14,7 @@ import {ChainEvent, ReorgEventData} from "../../../../src/chain/emitter.js";
 import {ReorgedForkChoice} from "../../../utils/mocks/forkchoice.js";
 import {connect} from "../../../utils/network.js";
 import {CacheItemType} from "../../../../src/chain/stateCache/types.js";
+import {CHECKPOINT_STATES_FOLDER} from "../../../../src/chain/stateCache/datastore/file.js";
 
 /**
  * Test different reorg scenarios to make sure the StateCache implementations are correct.
@@ -26,6 +28,10 @@ describe(
       SECONDS_PER_SLOT: 2,
     };
 
+    beforeEach(async () => {
+      await fs.promises.rm(CHECKPOINT_STATES_FOLDER, {recursive: true, force: true});
+    });
+
     const afterEachCallbacks: (() => Promise<unknown> | void)[] = [];
     afterEach(async () => {
       while (afterEachCallbacks.length > 0) {