erikras/redux-form

// @flow
export type Params = {
  initialized: boolean,
  trigger: string,
  blurredField: string,
  pristine: boolean,
  syncValidationPasses: boolean
}

const defaultShouldAsyncValidate = ({
  initialized,
  trigger,
  // blurredField,  // not used in default implementation
  pristine,
  syncValidationPasses
}: Params): boolean => {
  if (!syncValidationPasses) {
    return false
  }
  switch (trigger) {
    case 'blur':
    case 'change':
      // blurring
      return true
    case 'submit':
      // submitting, so only async validate if form is dirty or was never initialized
      // conversely, DON'T async validate if the form is pristine just as it was initialized
      return !pristine || !initialized
    default:
      return false
  }
}

export default defaultShouldAsyncValidate