Add ability to throw error instead of warning in tests

[hakunin]

In tests it would be nice to throw an error if the property isn't of its expected type.

It would be nice if this could be scoped to our own components and not 3rd party ones using 3rd party components, but thats not necesary.

People are already turning console.warning calls to throw errors, so this would be a nice upgrade for them.

[iainbeeston]

This would be really useful for anyone using create-react-app, as PropType errors would appear in the new error overlay

[seanadenise]

Related to previous conversation here.

[uniphil]

I just published a check-prop-types package that does this. The main export returns the error instead of logging it, and a helper assertPropTypes throws it.

#54 on this repo also has an interesting approach, using a callback instead.

[art-in]

I'm trying to use prop-types to validate js schema of external service response on server.
And surprised it's just generating console warnings.
How do I supposed to react to validation errors?

checkPropTypes should definitely generate some report (like suggested in #88), or at least return true/false. Anyway it would be nice for user to decide how validation results should be handled (log, throw error, etc).

[rumkin]

@artin-phares I've created typed-props library which has the same interface and produce an array of validation report issues.

[a-ignatov-parc]

There is a workaround for throwing an error on warnings. We can use getStack argument.

PropTypes.checkPropTypes(spec, values, 'prop', name, () => {
    process.nextTick(() => {
        throw new Error('Check has failed');
    });
});

This should work even in browsers with process.nextTick polyfill.

[asapach]

@a-ignatov-parc, won't nextTick cause it to fail after the test has already completed? Potentially even after test runner has already finished. Not very useful.

[a-ignatov-parc]

nextTick will be called before the current event loop continues, so it will throw after the warning is printed and before everything else.

[rumkin]

@a-ignatov-parc Thrown error will loose the stack in that way and it will not be captured in the place where it was thrown. Also printing of PropTypes' message will not be stopped.

[sarbbottam]

I am not sure what is the current state of this issue and the project.

I am using a small wrapper to throw error like so:

PropTypes.originalCheckPropTypes = PropTypes.checkPropTypes;
PropTypes.checkPropTypes = function(propTypes, attrs, attrsName, componentName) {
  const consoleError = console.error;
  console.error = function(message) {
    throw new Error(message);
  };
  PropTypes.originalCheckPropTypes(propTypes, attrs, attrsName, componentName);
  console.error = consoleError;
};