refactor: use fs.promises in cli/run, Part 1

cli/run/getConfigPath.ts

@@ -1,13 +1,13 @@
-import { readdirSync } from 'fs';
+import { promises as fs } from 'fs';
 import { resolve } from 'path';
 import { cwd } from 'process';
 import { handleError } from '../logging';
 
 const DEFAULT_CONFIG_BASE = 'rollup.config';
 
-export function getConfigPath(commandConfig: string | true): string {
+export async function getConfigPath(commandConfig: string | true): Promise<string> {
 	if (commandConfig === true) {
-		return resolve(findConfigFileNameInCwd());
+		return resolve(await findConfigFileNameInCwd());
 	}
 	if (commandConfig.slice(0, 5) === 'node:') {
 		const pkgName = commandConfig.slice(5);
@@ -30,8 +30,8 @@ export function getConfigPath(commandConfig: string | true): string {
 	return resolve(commandConfig);
 }
 
-function findConfigFileNameInCwd(): string {
-	const filesInWorkingDir = new Set(readdirSync(cwd()));
+async function findConfigFileNameInCwd(): Promise<string> {
+	const filesInWorkingDir = new Set(await fs.readdir(cwd()));
 	for (const extension of ['mjs', 'cjs', 'ts']) {
 		const fileName = `${DEFAULT_CONFIG_BASE}.${extension}`;
 		if (filesInWorkingDir.has(fileName)) return fileName;

cli/run/index.ts

@@ -89,7 +89,7 @@ async function getConfigs(
 	command: any
 ): Promise<{ options: MergedRollupOptions[]; warnings: BatchWarnings }> {
 	if (command.config) {
-		const configFile = getConfigPath(command.config);
+		const configFile = await getConfigPath(command.config);
 		const { options, warnings } = await loadAndParseConfigFile(configFile, command);
 		return { options, warnings };
 	}

cli/run/loadConfigFile.ts

@@ -1,4 +1,4 @@
-import { realpathSync } from 'fs';
+import { promises as fs } from 'fs';
 import { extname, isAbsolute } from 'path';
 import { pathToFileURL } from 'url';
 import * as rollup from '../../src/node-entry';
@@ -57,7 +57,7 @@ async function loadConfigFile(
 	return getConfigList(configFileExport, commandOptions);
 }
 
-function getDefaultFromCjs(namespace: GenericConfigObject) {
+function getDefaultFromCjs(namespace: GenericConfigObject): unknown {
 	return namespace.__esModule ? namespace.default : namespace;
 }
 
@@ -103,7 +103,7 @@ async function getDefaultFromTranspiledConfigFile(
 }
 
 async function loadConfigFromBundledFile(fileName: string, bundledCode: string): Promise<unknown> {
-	const resolvedFileName = realpathSync(fileName);
+	const resolvedFileName = await fs.realpath(fileName);
 	const extension = extname(resolvedFileName);
 	const defaultLoader = require.extensions[extension];
 	require.extensions[extension] = (module: NodeModule, requiredFileName: string) => {

cli/run/watch-cli.ts

@@ -1,4 +1,4 @@
-import { type FSWatcher, readFileSync } from 'fs';
+import { promises as fs, type FSWatcher } from 'fs';
 import process from 'process';
 import chokidar from 'chokidar';
 import dateTime from 'date-time';
@@ -23,7 +23,7 @@ export async function watch(command: Record<string, any>): Promise<void> {
 	let watcher: RollupWatcher;
 	let configWatcher: FSWatcher;
 	let resetScreen: (heading: string) => void;
-	const configFile = command.config ? getConfigPath(command.config) : null;
+	const configFile = command.config ? await getConfigPath(command.config) : null;
 
 	onExit(close);
 	process.on('uncaughtException', close);
@@ -41,7 +41,7 @@ export async function watch(command: Record<string, any>): Promise<void> {
 
 		async function reloadConfigFile() {
 			try {
-				const newConfigFileData = readFileSync(configFile, 'utf-8');
+				const newConfigFileData = await fs.readFile(configFile, 'utf8');
 				if (newConfigFileData === configFileData) {
 					return;
 				}