Import from node:fs/promises

browser/src/fs.ts

@@ -1,7 +1,5 @@
 import { throwNoFileSystem } from './error';
 
-export const promises = {
-	mkdir: throwNoFileSystem('fs.mkdir'),
-	readFile: throwNoFileSystem('fs.readFile'),
-	writeFile: throwNoFileSystem('fs.writeFile')
-};
+export const mkdir = throwNoFileSystem('fs.mkdir');
+export const readFile = throwNoFileSystem('fs.readFile');
+export const writeFile = throwNoFileSystem('fs.writeFile');

build-plugins/generate-license-file.ts

@@ -1,4 +1,4 @@
-import { promises as fs } from 'node:fs';
+import { readFile, writeFile } from 'node:fs/promises';
 import { join } from 'node:path';
 import type { PluginImpl } from 'rollup';
 import license, { type Dependency, type Person } from 'rollup-plugin-license';
@@ -7,7 +7,7 @@ async function generateLicenseFile(
 	directory: string,
 	dependencies: readonly Dependency[]
 ): Promise<void> {
-	const coreLicense = await fs.readFile('LICENSE-CORE.md', 'utf8');
+	const coreLicense = await readFile('LICENSE-CORE.md', 'utf8');
 	const licenses = new Set<string>();
 	const dependencyLicenseTexts = [...dependencies]
 		.filter(({ name }) => name !== '@rollup/browser')
@@ -58,9 +58,9 @@ async function generateLicenseFile(
 		`# Bundled dependencies:\n` +
 		dependencyLicenseTexts;
 	const licenseFile = join(directory, 'LICENSE.md');
-	const existingLicenseText = await fs.readFile(licenseFile, 'utf8');
+	const existingLicenseText = await readFile(licenseFile, 'utf8');
 	if (existingLicenseText !== licenseText) {
-		await fs.writeFile(licenseFile, licenseText);
+		await writeFile(licenseFile, licenseText);
 		console.warn('LICENSE.md updated. You should commit the updated file.');
 	}
 }

build-plugins/get-banner.ts

@@ -1,5 +1,5 @@
 import { exec } from 'node:child_process';
-import { promises as fs } from 'node:fs';
+import { readFile } from 'node:fs/promises';
 import { env } from 'node:process';
 import { promisify } from 'node:util';
 
@@ -31,6 +31,6 @@ export default function getBanner(): Promise<string> {
 				console.error('Could not determine commit hash:', error);
 				return 'unknown';
 			}),
-		fs.readFile(new URL('../package.json', import.meta.url), 'utf8')
+		readFile(new URL('../package.json', import.meta.url), 'utf8')
 	]).then(([commit, package_]) => generateBanner(commit, JSON.parse(package_).version)));
 }

cli/run/getConfigPath.ts

@@ -1,4 +1,4 @@
-import { promises as fs } from 'node:fs';
+import { readdir } from 'node:fs/promises';
 import { resolve } from 'node:path';
 import { cwd } from 'node:process';
 import { errorMissingExternalConfig } from '../../src/utils/error';
@@ -31,7 +31,7 @@ export async function getConfigPath(commandConfig: string | true): Promise<strin
 }
 
 async function findConfigFileNameInCwd(): Promise<string> {
-	const filesInWorkingDirectory = new Set(await fs.readdir(cwd()));
+	const filesInWorkingDirectory = new Set(await readdir(cwd()));
 	for (const extension of ['mjs', 'cjs', 'ts']) {
 		const fileName = `${DEFAULT_CONFIG_BASE}.${extension}`;
 		if (filesInWorkingDirectory.has(fileName)) return fileName;

cli/run/loadConfigFile.ts

@@ -1,4 +1,4 @@
-import { promises as fs } from 'node:fs';
+import { unlink, writeFile } from 'node:fs/promises';
 import { dirname, isAbsolute, join } from 'node:path';
 import process from 'node:process';
 import { pathToFileURL } from 'node:url';
@@ -132,12 +132,12 @@ async function loadConfigFromWrittenFile(
 	bundledFileName: string,
 	bundledCode: string
 ): Promise<unknown> {
-	await fs.writeFile(bundledFileName, bundledCode);
+	await writeFile(bundledFileName, bundledCode);
 	try {
 		return (await import(pathToFileURL(bundledFileName).href)).default;
 	} finally {
 		// Not awaiting here saves some ms while potentially hiding a non-critical error
-		fs.unlink(bundledFileName);
+		unlink(bundledFileName);
 	}
 }
 

cli/run/watch-cli.ts

@@ -1,4 +1,5 @@
-import { promises as fs, type FSWatcher } from 'node:fs';
+import type { FSWatcher } from 'node:fs';
+import { readFile } from 'node:fs/promises';
 import process from 'node:process';
 import chokidar from 'chokidar';
 import dateTime from 'date-time';
@@ -43,7 +44,7 @@ export async function watch(command: Record<string, any>): Promise<void> {
 
 		async function reloadConfigFile() {
 			try {
-				const newConfigFileData = await fs.readFile(configFile, 'utf8');
+				const newConfigFileData = await readFile(configFile, 'utf8');
 				if (newConfigFileData === configFileData) {
 					return;
 				}

scripts/find-config.js

@@ -1,8 +1,8 @@
-import { promises as fs } from 'node:fs';
+import { readdir } from 'node:fs/promises';
 import { resolve } from 'node:path';
 
 export async function findConfigFileName(targetDirectory) {
-	const filesInWorkingDirectory = new Set(await fs.readdir(targetDirectory));
+	const filesInWorkingDirectory = new Set(await readdir(targetDirectory));
 	for (const extension of ['mjs', 'cjs', 'ts', 'js']) {
 		const fileName = `rollup.config.${extension}`;
 		if (filesInWorkingDirectory.has(fileName)) return resolve(targetDirectory, fileName);

src/ModuleLoader.ts

@@ -30,7 +30,7 @@ import {
 	errorUnresolvedImport,
 	errorUnresolvedImportTreatedAsExternal
 } from './utils/error';
-import { promises as fs } from './utils/fs';
+import { readFile } from './utils/fs';
 import { doAssertionsDiffer, getAssertionsFromImportExpression } from './utils/parseAssertions';
 import { isAbsolute, isRelative, resolve } from './utils/path';
 import relativeId from './utils/relativeId';
@@ -259,7 +259,7 @@ export class ModuleLoader {
 		try {
 			source = await this.graph.fileOperationQueue.run(
 				async () =>
-					(await this.pluginDriver.hookFirst('load', [id])) ?? (await fs.readFile(id, 'utf8'))
+					(await this.pluginDriver.hookFirst('load', [id])) ?? (await readFile(id, 'utf8'))
 			);
 		} catch (error_: any) {
 			let message = `Could not load ${id}`;

src/rollup/rollup.ts

@@ -10,7 +10,7 @@ import {
 	// eslint-disable-next-line unicorn/prevent-abbreviations
 	errorMissingFileOrDirOption
 } from '../utils/error';
-import { promises as fs } from '../utils/fs';
+import { mkdir, writeFile } from '../utils/fs';
 import { catchUnfinishedHookActions } from '../utils/hookActions';
 import { normalizeInputOptions } from '../utils/options/normalizeInputOptions';
 import { normalizeOutputOptions } from '../utils/options/normalizeOutputOptions';
@@ -268,9 +268,9 @@ async function writeOutputFile(
 	const fileName = resolve(outputOptions.dir || dirname(outputOptions.file!), outputFile.fileName);
 
 	// 'recursive: true' does not throw if the folder structure, or parts of it, already exist
-	await fs.mkdir(dirname(fileName), { recursive: true });
+	await mkdir(dirname(fileName), { recursive: true });
 
-	return fs.writeFile(fileName, outputFile.type === 'asset' ? outputFile.source : outputFile.code);
+	return writeFile(fileName, outputFile.type === 'asset' ? outputFile.source : outputFile.code);
 }
 
 /**

src/utils/fs.ts

@@ -1 +1 @@
-export * from 'node:fs';
+export * from 'node:fs/promises';

src/utils/resolveId.ts

@@ -1,7 +1,7 @@
 import type { ModuleLoaderResolveId } from '../ModuleLoader';
 import type { CustomPluginOptions, Plugin, ResolveIdResult } from '../rollup/types';
 import type { PluginDriver } from './PluginDriver';
-import { promises as fs } from './fs';
+import { lstat, readdir, realpath } from './fs';
 import { basename, dirname, isAbsolute, resolve } from './path';
 import { resolveIdViaPlugins } from './resolveIdViaPlugins';
 
@@ -55,13 +55,13 @@ async function addJsExtensionIfNecessary(
 
 async function findFile(file: string, preserveSymlinks: boolean): Promise<string | undefined> {
 	try {
-		const stats = await fs.lstat(file);
+		const stats = await lstat(file);
 		if (!preserveSymlinks && stats.isSymbolicLink())
-			return await findFile(await fs.realpath(file), preserveSymlinks);
+			return await findFile(await realpath(file), preserveSymlinks);
 		if ((preserveSymlinks && stats.isSymbolicLink()) || stats.isFile()) {
 			// check case
 			const name = basename(file);
-			const files = await fs.readdir(dirname(file));
+			const files = await readdir(dirname(file));
 
 			if (files.includes(name)) return file;
 		}

test/cli/samples/watch/close-stdin/wrapper.js

@@ -1,21 +1,21 @@
 #!/usr/bin/env node
 
-const stream = require('stream');
-const { mkdirSync, readFileSync, writeFileSync } = require('fs');
+const { mkdirSync, readFileSync, writeFileSync } = require('node:fs');
+const { resolve } = require('node:path');
+const { Readable } = require('node:stream');
 const chokidar = require('chokidar');
-const path = require('path');
 
 delete process.stdin;
-process.stdin = new stream.Readable({
+process.stdin = new Readable({
 	encoding: 'utf8',
 	read() {
 		return null;
 	}
 });
 
-const outputDir = path.resolve(__dirname, '_actual');
+const outputDir = resolve(__dirname, '_actual');
 mkdirSync(outputDir);
-const outputFile = path.resolve(outputDir, 'out.js');
+const outputFile = resolve(outputDir, 'out.js');
 const INITIAL_OUTPUT = 'NOT WRITTEN';
 writeFileSync(outputFile, INITIAL_OUTPUT);