prop-type

Small wrapper to wrap your custom type check so that you can use myCustomType.isRequired in a similar fasion to React's built-in types. React expects type-checks to return an Error object upon faillure and nothing otherwise.

Install

npm install prop-type

Usage:

    var check = function(props, propName){
   if(props[propName]) return;
   return Error("Test error");
    };
    
    var type = propType(check);
    
    
    assert.ok(!type({}, "foo"), "undefined is ok, as the type is optional by default");
    assert.ok( type.isRequired({}, "foo") instanceof Error, "But null is not ok for required");
    assert.equal( type.isRequired({ foo: true }, "foo"), undefined, "Return undefined when the typecheck is ok");