How to use the @yarnpkg/fslib.xfs.changeFilePromise function in @yarnpkg/fslib

async persistManifest() {
    const data = {};
    this.manifest.exportTo(data);

    const content = `${JSON.stringify(data, null, this.manifest.indent)}\n`;
    await xfs.changeFilePromise(ppath.join(this.cwd, toFilename(`package.json`)), content);
  }
}

async persistLockfile() {
    const lockfilePath = ppath.join(this.cwd, this.configuration.get(`lockfileFilename`));
    const lockfileContent = this.generateLockfile();

    await xfs.changeFilePromise(lockfilePath, lockfileContent);
  }

const addVSCodeWorkspaceSettings = async (projectRoot: PortablePath, settings: any) => {
  const settingsPath = ppath.join(projectRoot, `.vscode/settings.json` as PortablePath);
  const content = await xfs.existsPromise(settingsPath) ? await xfs.readFilePromise(settingsPath, `utf8`) : `{}`;

  const data = json5.parse(content);
  const patched = `${json5.stringify({...data, ...settings}, null, 2)}\n`;

  await xfs.mkdirpPromise(ppath.dirname(settingsPath));
  await xfs.changeFilePromise(settingsPath, patched);
};

return [structUtils.stringifyLocator(pkg), hash, name];
    });

    if (bstateData.length > 0) {
      let bstateFile = `# Warning: This file is automatically generated. Removing it is fine, but will\n# cause all your builds to become invalidated.\n`;

      for (const [locatorString, locatorHash, buildHash] of miscUtils.sortMap(bstateData, [d => d[0], d => d[1]])) {
        bstateFile += `\n`;
        bstateFile += `# ${locatorString}\n`;
        bstateFile += `${JSON.stringify(locatorHash)}:\n`;
        bstateFile += `  ${buildHash}\n`;
      }

      await xfs.mkdirpPromise(ppath.dirname(bstatePath));
      await xfs.changeFilePromise(bstatePath, bstateFile);
    } else {
      await xfs.removePromise(bstatePath);
    }
  }

const pnpDataPath = this.opts.project.configuration.get(`pnpDataPath`);

    const pnpSettings: PnpSettings = {
      blacklistedLocations,
      dependencyTreeRoots,
      enableTopLevelFallback,
      fallbackExclusionList,
      ignorePattern,
      packageRegistry,
      shebang,
    };

    if (this.opts.project.configuration.get(`pnpEnableInlining`)) {
      const loaderFile = generateInlinedScript(pnpSettings);

      await xfs.changeFilePromise(pnpPath, loaderFile);
      await xfs.chmodPromise(pnpPath, 0o755);

      await xfs.removePromise(pnpDataPath);
    } else {
      const dataLocation = ppath.relative(ppath.dirname(pnpPath), pnpDataPath);
      const {dataFile, loaderFile} = generateSplitScript({...pnpSettings, dataLocation});

      await xfs.changeFilePromise(pnpPath, loaderFile);
      await xfs.chmodPromise(pnpPath, 0o755);

      await xfs.changeFilePromise(pnpDataPath, dataFile);
      await xfs.chmodPromise(pnpDataPath, 0o644);
    }

    const pnpUnpluggedFolder = this.opts.project.configuration.get(`pnpUnpluggedFolder`);
    if (this.unpluggedPaths.size === 0) {

const [left, right] = getVariants(file);

  let parsedLeft;
  let parsedRight;

  try {
    parsedLeft = parseSyml(left);
    parsedRight = parseSyml(right);
  } catch (error) {
    throw new ReportError(MessageName.AUTOMERGE_FAILED_TO_PARSE, `The individual variants of the lockfile failed to parse`);
  }

  const merged = Object.assign({}, parsedLeft, parsedRight);
  const serialized = stringifySyml(merged);

  await xfs.changeFilePromise(lockfilePath, serialized);

  return true;
}

const nextValue = typeof patch[key] === `function`
        ? patch[key](currentValue)
        : patch[key];

      if (currentValue === nextValue)
        continue;

      current[key] = nextValue;
      patched = true;
    }

    if (!patched)
      return;

    await xfs.changeFilePromise(configurationPath, stringifySyml(current));
  }

if (this.opts.project.configuration.get(`pnpEnableInlining`)) {
      const loaderFile = generateInlinedScript(pnpSettings);

      await xfs.changeFilePromise(pnpPath, loaderFile);
      await xfs.chmodPromise(pnpPath, 0o755);

      await xfs.removePromise(pnpDataPath);
    } else {
      const dataLocation = ppath.relative(ppath.dirname(pnpPath), pnpDataPath);
      const {dataFile, loaderFile} = generateSplitScript({...pnpSettings, dataLocation});

      await xfs.changeFilePromise(pnpPath, loaderFile);
      await xfs.chmodPromise(pnpPath, 0o755);

      await xfs.changeFilePromise(pnpDataPath, dataFile);
      await xfs.chmodPromise(pnpDataPath, 0o644);
    }

    const pnpUnpluggedFolder = this.opts.project.configuration.get(`pnpUnpluggedFolder`);
    if (this.unpluggedPaths.size === 0) {
      await xfs.removePromise(pnpUnpluggedFolder);
    } else {
      for (const entry of await xfs.readdirPromise(pnpUnpluggedFolder)) {
        const unpluggedPath = ppath.resolve(pnpUnpluggedFolder, entry);
        if (!this.unpluggedPaths.has(unpluggedPath)) {
          await xfs.removePromise(unpluggedPath);
        }
      }
    }
  }