fix: avoid faulty rename when installing

Fixes #233, which Andrea ran into when testing.

Instead of staging and renaming, which tends to fail on Windows, write a 'completed' file when the install is done.

CHANGELOG.md

@@ -1,5 +1,9 @@
 # Changelog
 
+### 2.3.6 | 2022-10-24
+
+- Fix windows sometimes failing on EPERM in download (again)
+
 ### 2.3.5 | 2022-10-04
 
 - Fix windows sometimes failing on EPERM in download

lib/download.ts

@@ -27,7 +27,6 @@ import {
 	streamToBuffer,
 	systemDefaultPlatform,
 } from './util';
-import * as timers from 'timers/promises';
 
 const extensionRoot = process.cwd();
 const pipelineAsync = promisify(pipeline);
@@ -332,6 +331,8 @@ function spawnDecompressorChild(command: string, args: ReadonlyArray<string>, in
 
 export const defaultCachePath = path.resolve(extensionRoot, '.vscode-test');
 
+const COMPLETE_FILE_NAME = 'is-complete';
+
 /**
  * Download and unzip a copy of VS Code.
  * @returns Promise of `vscodeExecutablePath`.
@@ -368,7 +369,7 @@ export async function download(options: Partial<DownloadOptions> = {}): Promise<
 	reporter.report({ stage: ProgressReportStage.ResolvedVersion, version });
 
 	const downloadedPath = path.resolve(cachePath, makeDownloadDirName(platform, version));
-	if (fs.existsSync(downloadedPath)) {
+	if (fs.existsSync(path.join(downloadedPath, COMPLETE_FILE_NAME))) {
 		if (isInsiderVersionIdentifier(version)) {
 			reporter.report({ stage: ProgressReportStage.FetchingInsidersMetadata });
 			const { version: currentHash, date: currentDate } = insidersDownloadDirMetadata(downloadedPath, platform);
@@ -408,10 +409,7 @@ export async function download(options: Partial<DownloadOptions> = {}): Promise<
 
 	for (let i = 0; ; i++) {
 		try {
-			// Use a staging directory and rename after unzipping so partially-
-			// downloaded/unzipped files aren't "stuck" being used.
-			const downloadStaging = `${downloadedPath}.tmp`;
-			await fs.promises.rm(downloadStaging, { recursive: true, force: true });
+			await fs.promises.rm(downloadedPath, { recursive: true, force: true });
 
 			const { stream, format } = await downloadVSCodeArchive({
 				version,
@@ -422,22 +420,9 @@ export async function download(options: Partial<DownloadOptions> = {}): Promise<
 			});
 			// important! do not put anything async here, since unzipVSCode will need
 			// to start consuming the stream immediately.
-			await unzipVSCode(reporter, downloadStaging, stream, platform, format);
-
-			// Windows file handles can get released asynchronously, give it a few retries:
-			for (let attempts = 20; attempts >= 0; attempts--) {
-				try {
-					await fs.promises.rename(downloadStaging, downloadedPath);
-					break;
-				} catch (e) {
-					if (attempts === 0) {
-						throw e;
-					} else {
-						await timers.setTimeout(200);
-					}
-				}
-			}
+			await unzipVSCode(reporter, downloadedPath, stream, platform, format);
 
+			await fs.promises.writeFile(path.join(downloadedPath, COMPLETE_FILE_NAME), '');
 			reporter.report({ stage: ProgressReportStage.NewInstallComplete, downloadedPath });
 			break;
 		} catch (error) {