refactor(utils): add function "lockfilePath"

and use it in "MongoBinary"

packages/mongodb-memory-server-core/src/util/MongoBinary.ts

@@ -1,10 +1,9 @@
 import os from 'os';
-import path from 'path';
 import MongoBinaryDownload from './MongoBinaryDownload';
 import resolveConfig, { envToBool, ResolveConfigVariables } from './resolveConfig';
 import debug from 'debug';
 import * as semver from 'semver';
-import { assertion, isNullOrUndefined, mkdir } from './utils';
+import { assertion, isNullOrUndefined, lockfilePath, mkdir } from './utils';
 import { spawnSync } from 'child_process';
 import { LockFile } from './lockfile';
 import { DryMongoBinary, BaseDryMongoBinaryOptions } from './DryMongoBinary';
@@ -31,7 +30,7 @@ export class MongoBinary {
     await mkdir(downloadDir);
 
     /** Lockfile path */
-    const lockfile = path.resolve(downloadDir, `${version}.lock`);
+    const lockfile = lockfilePath(downloadDir, version);
     log(`download: Waiting to acquire Download lock for file "${lockfile}"`);
     // wait to get a lock
     // downloading of binaries may be quite long procedure

packages/mongodb-memory-server-core/src/util/utils.ts

@@ -379,3 +379,13 @@ export function md5(content: BinaryLike): string {
 export async function md5FromFile(file: string): Promise<string> {
   return md5(await fspromises.readFile(file));
 }
+
+/**
+ * Helper function to get the lockfile for the provided `version` in `downloadDir`
+ * @param downloadDir The Download directory of the binary
+ * @param version The version to be downlaoded
+ * @returns The lockfile path
+ */
+export function lockfilePath(downloadDir: string, version: string): string {
+  return path.resolve(downloadDir, `${version}.lock`);
+}