Monkey patch process.stdout to allow file logging (disappearing streams anyone?)

stdout-monkeypatch.ts

var origWrite = process.stdout.write;

function monkey(callback){

  // callback = callback).function || function(){ };

  return ({
    patch : function(cb){
      var self = this;
      this.state = { patched : true };
      // callback = type(cb).function || callback;
      process.stdout.write = function(str, enc, cb){
        callback.call(self, str, enc, cb);
      };
      return this;
    },
    restore : function(data, enc, cb){
      process.stdout.write = origWrite;
      this.state = { restored : true };
      return data ? this.write(data, enc, cb) : this;
    },
    listen : function(cb){
      var self = this;
      this.state = { patched : true, listening : true };
      // callback = type(cb).function || callback;
      process.stdout.write = function(str, enc, cb){
        callback.call(self, str, enc, cb);
        origWrite.call(scope, str, enc, cb);
      };
      return this;
    },
    log : function (/* arguments */){

      this.restore();
      var args = arguments;
      var len = args.length;

      if( typeof args[len-1] === 'string' ){
        args[len-1] = args[len-1].trim();
      }
      console.log.apply(console, args);

      return this;
    },
    write : function(str, enc, cb){
      origWrite.call(scope, str, enc, cb);
      return this;
    }
  }).patch();
}
monkey(
  function(msg: string) {
    fs.appendFileSync('/tmp/mnt/logOutput2.txt', `${msg}\n`)
    this.write(`${msg}\n`)
    // origWrite(`${msg}\n`)
      // return origWrite(`${msg}\n`)
    }
)