Quick Start

Flow-Dynamic

A helper library link runtime type check to static flow check.

How To:

Assume you have a resolver, which the passed args is out of static type check.

const resolver = (src:any) => {
  // .... doing something
  return src;
});

to check it,just wrap it by check functions.
like: sourceCheck(sourceCaster, checkedResolver) .checkedResolver is your old resolver .And sourceCaster is a type caster(which do dynamic check for args,and link them to flow type.)

const resolver = sourceCheck(
(src) => ({
  mail:pro.isString.isEmail(src.mail) // check src.mail .
}), (src) => {
  // .... doing something
  return src;
});

Like React,you only need to test the field will be used. As above,we test mail,so the type checked src pass to your old resolver is {mail:string}(with isEmail ensuring).
Let's test it:

function test() {
  const user = {
    id:'aaa',
    name:'tom',
    age:28,
    mail:'xx@mail.com'// will pass, and 'xx@mail' will throw a error.
  };
  const rt = resolver(user, {}, {}, ({}:any));
  return rt;
}