cleanup.js

var fs = require('fs');

console.log(__dirname);
var appPath = __dirname.split('node_modules')[0];
rmDir(appPath +"//");

function rmDir(dirPath) {
    var findWorkingDir = dirPath;
    console.log("findWorkingDir", findWorkingDir);

    if (findWorkingDir.indexOf('node_modules') === -1) {
        var files = fs.readdirSync(findWorkingDir);

        if (files.length > 0) {
            for (var i = 0; i < files.length; i++) {

                var filePath = findWorkingDir + files[i];

                if (filePath.indexOf('test') === -1 && filePath.indexOf('dist') === -1) {
                    if (files[i].charAt(0) !== ".") {
                        if (fs.statSync(filePath).isFile()) {
                            if (files[i].indexOf('.js') !== -1) {
                                if (files[i] !== "karma.conf.js" &&
                                    files[i] !== "webpack.config.js" &&
                                    files[i] !== "tsloader.js" &&
                                    files[i] !== "build.js" &&
                                    files[i] !== "cleanup.js" &&       
                                    files[i] !== "rollup.config.esm.js" &&    
                                    files[i] !== "rollup.config.umd.js" &&                                                              
                                    files[i].indexOf('.json') === -1 &&
                                    files[i].indexOf('.js.map') === -1) {
                                    fs.unlinkSync(filePath);
                                    //fs.rename(filePath, filePath.replace(appPath, appPath + "/test/mock/"));
                                    console.log("delete", files[i]);
                                }
                            }
                        }
                        else {
                            rmDir(filePath + "/");
                        }
                    }
                }
            }
        }
    }
}

console.log('all js files are deleted');