function monitorCodeUse(eventName, data) {
  ("production" !== process.env.NODE_ENV ? invariant(
    eventName && !/[^a-z0-9_]/.test(eventName),
    'You must provide an eventName using only the characters [a-z0-9_]'
  ) : invariant(eventName && !/[^a-z0-9_]/.test(eventName)));
}
Provides open-source compatible instrumentation for monitoring certain API
uses before we're ready to issue a warning or refactor. It accepts an event
name which may only contain the characters [a-z0-9_] and an optional data
object with further information.