3.js

var foo = "foo1";

const ctx = {
  func: variable => {
    console.log(variable);
  }
};

function withedYourCode(code) {
  code = "with(shadow) {" + code + "}";
  return new Function("shadow", code);
}

const access_white_list = ["func"];

const code = `func(foo)`;

const ctxProxy = new Proxy(ctx, {
  has: (target, prop) => {
    if (access_white_list.includes(prop)) {
      return target.hasOwnProperty(prop);
    }
    if (!target.hasOwnProperty(prop)) {
      throw new Error(`Not found - ${prop}!`);
    }
    return true;
  }
});

function littlePoorSandbox(code, ctx) {
  withedYourCode(code).call(ctx, ctx); 
}
littlePoorSandbox(code, ctxProxy);