'use strict'; const common = require('../common'); // The following tests validate base functionality for the fs.promises // FileHandle.write method. const fs = require('fs'); const { open } = fs.promises; const path = require('path'); const tmpdir = require('../common/tmpdir'); const assert = require('assert'); const tmpDir = tmpdir.path; tmpdir.refresh(); async function validateWrite() { const filePathForHandle = path.resolve(tmpDir, 'tmp-write.txt'); const fileHandle = await open(filePathForHandle, 'w+'); const buffer = Buffer.from('Hello world'.repeat(100), 'utf8'); await fileHandle.write(buffer, 0, buffer.length); const readFileData = fs.readFileSync(filePathForHandle); assert.deepStrictEqual(buffer, readFileData); await fileHandle.close(); } async function validateEmptyWrite() { const filePathForHandle = path.resolve(tmpDir, 'tmp-empty-write.txt'); const fileHandle = await open(filePathForHandle, 'w+'); const buffer = Buffer.from(''); // empty buffer await fileHandle.write(buffer, 0, buffer.length); const readFileData = fs.readFileSync(filePathForHandle); assert.deepStrictEqual(buffer, readFileData); await fileHandle.close(); } async function validateNonUint8ArrayWrite() { const filePathForHandle = path.resolve(tmpDir, 'tmp-data-write.txt'); const fileHandle = await open(filePathForHandle, 'w+'); const buffer = Buffer.from('Hello world', 'utf8').toString('base64'); await fileHandle.write(buffer, 0, buffer.length); const readFileData = fs.readFileSync(filePathForHandle); assert.deepStrictEqual(Buffer.from(buffer, 'utf8'), readFileData); await fileHandle.close(); } async function validateNonStringValuesWrite() { const filePathForHandle = path.resolve(tmpDir, 'tmp-non-string-write.txt'); const fileHandle = await open(filePathForHandle, 'w+'); const nonStringValues = [ 123, {}, new Map(), null, undefined, 0n, () => {}, Symbol(), true, new String('notPrimitive'), { toString() { return 'amObject'; } }, { [Symbol.toPrimitive]: (hint) => 'amObject' }, ]; for (const nonStringValue of nonStringValues) { await assert.rejects( fileHandle.write(nonStringValue), { message: /"buffer"/, code: 'ERR_INVALID_ARG_TYPE' } ); } await fileHandle.close(); } Promise.all([ validateWrite(), validateEmptyWrite(), validateNonUint8ArrayWrite(), validateNonStringValuesWrite(), ]).then(common.mustCall());