microsoft/vscode-react-native

// Copyright (c) Microsoft Corporation. All rights reserved.
// Licensed under the MIT license. See LICENSE file in the project root for details.

import * as fs from "fs";
import * as Q from "q";

export class FileSystemUtil {

    public ensureDirectory(dir: string): Q.Promise<void> {
        return Q.nfcall(fs.stat, dir).then((stat: fs.Stats): void => {
            if (stat.isDirectory()) {
                return;
            } else {
                throw new Error(`Expected ${dir} to be a directory`);
            }
        }, (err: Error & {code?: string}): Q.Promise<any> => {
            if (err && err.code === "ENOENT") {
                return Q.nfcall(fs.mkdir, dir);
            } else {
                throw err;
            }
        });
    }

    public ensureFileWithContents(file: string, contents: string): Q.Promise<void> {
        return Q.nfcall(fs.stat, file).then((stat: fs.Stats): void => {
            if (!stat.isFile()) {
                throw new Error(`Expected ${file} to be a file`);
            }
            // The file already exists, assume the contents are good and do not touch it.
        }, (err: Error & {code?: string}): Q.Promise<any> => {
            if (err && err.code === "ENOENT") {
                return Q.nfcall(fs.writeFile, file, contents);
            } else {
                throw err;
            }
        });
    }
}