fs: make sure that file is truncated in writeFile

[thefourtheye]

Simple Reproduction of the Bug

'use strict';

const assert = require('assert');
const fs = require('fs');

const fileName = 'test.txt';
fs.writeFileSync(fileName, '123');
fs.writeFileSync(fileName, '0');
const result1 = fs.readFileSync(fileName, 'utf8');
fs.unlinkSync(fileName);

const fd = fs.openSync(fileName, 'w');
fs.writeFileSync(fd, '123');
fs.writeFileSync(fd, '0');
fs.closeSync(fd);
const result2 = fs.readFileSync(fileName, 'utf8');
fs.unlinkSync(fileName);

assert.deepStrictEqual(result2, result1);
// + expected - actual
//
//- '023'
//+ '0'

Fixes: #22554

---

cc @vsemozhetbyt @nodejs/fs

Checklist

• make -j4 test (UNIX), or vcbuild test (Windows) passes
• tests and/or benchmarks are included
• documentation is changed or added
• commit message follows commit guidelines

[nodejs-github-bot]

@thefourtheye build started: https://ci.nodejs.org/blue/organizations/jenkins/node-test-pull-request-lite-pipeline/detail/node-test-pull-request-lite-pipeline/1074/pipeline

[thefourtheye]

This PR is blocked by #23136

[thefourtheye]

Bump @nodejs/fs

[jasnell]

This is highly unlikely to make the 11.0.0 cutoff since the blocking PR has not yet landed.

[thefourtheye]

As per the decision in #23433, the behaviour of writeFile is changed to be consistent with readFile, by making both of them start from the current position they are used with file descriptors. So closing this.