Piping into Code fails if data writes delayed (fix #155341) (#156973)

src/vs/code/node/cli.ts

@@ -179,7 +179,7 @@ export async function main(argv: string[]): Promise<any> {
 
 				// returns a file path where stdin input is written into (write in progress).
 				try {
-					readFromStdin(stdinFilePath, !!verbose); // throws error if file can not be written
+					await readFromStdin(stdinFilePath, !!verbose); // throws error if file can not be written
 
 					// Make sure to open tmp file
 					addArg(argv, stdinFilePath);

src/vs/platform/environment/node/stdin.ts

@@ -39,26 +39,33 @@ export function getStdinFilePath(): string {
 }
 
 export async function readFromStdin(targetPath: string, verbose: boolean): Promise<void> {
-	let encoding = await resolveTerminalEncoding(verbose);
 
-	const iconv = await import('@vscode/iconv-lite-umd');
+	let [encoding, iconv] = await Promise.all([
+		resolveTerminalEncoding(verbose),	// respect terminal encoding when piping into file
+		import('@vscode/iconv-lite-umd'),	// lazy load encoding module for usage
+		Promises.appendFile(targetPath, '') // make sure file exists right away (https://github.com/microsoft/vscode/issues/155341)
+	]);
+
 	if (!iconv.encodingExists(encoding)) {
 		console.log(`Unsupported terminal encoding: ${encoding}, falling back to UTF-8.`);
 		encoding = 'utf8';
 	}
 
-	// Pipe into tmp file using terminals encoding
 	// Use a `Queue` to be able to use `appendFile`
 	// which helps file watchers to be aware of the
 	// changes because each append closes the underlying
 	// file descriptor.
 	// (https://github.com/microsoft/vscode/issues/148952)
-	const decoder = iconv.getDecoder(encoding);
+
 	const appendFileQueue = new Queue();
+
+	const decoder = iconv.getDecoder(encoding);
+
 	process.stdin.on('data', chunk => {
 		const chunkStr = decoder.write(chunk);
 		appendFileQueue.queue(() => Promises.appendFile(targetPath, chunkStr));
 	});
+
 	process.stdin.on('end', () => {
 		const end = decoder.end();
 		if (typeof end === 'string') {

src/vs/server/node/server.cli.ts

@@ -87,7 +87,7 @@ const cliRemoteAuthority = process.env['VSCODE_CLI_AUTHORITY'] as string;
 const cliStdInFilePath = process.env['VSCODE_STDIN_FILE_PATH'] as string;
 
 
-export function main(desc: ProductDescription, args: string[]): void {
+export async function main(desc: ProductDescription, args: string[]): Promise<void> {
 	if (!cliPipe && !cliCommand) {
 		console.log('Command is only available in WSL or inside a Visual Studio Code terminal.');
 		return;
@@ -184,7 +184,7 @@ export function main(desc: ProductDescription, args: string[]): void {
 			let stdinFilePath = cliStdInFilePath;
 			if (!stdinFilePath) {
 				stdinFilePath = getStdinFilePath();
-				readFromStdin(stdinFilePath, verbose); // throws error if file can not be written
+				await readFromStdin(stdinFilePath, verbose); // throws error if file can not be written
 			}
 
 			// Make sure to open tmp file
@@ -460,5 +460,6 @@ function mapFileToRemoteUri(uri: string): string {
 }
 
 const [, , productName, version, commit, executableName, ...remainingArgs] = process.argv;
-main({ productName, version, commit, executableName }, remainingArgs);
-
+main({ productName, version, commit, executableName }, remainingArgs).then(null, err => {
+	console.error(err.message || err.stack || err);
+});