title: Redux-Form Field-Level Validation: Why aren't the error messages showing?
body: <p>In using redux-form with React, I'm having an issue where the error messages are not displaying for field-level input validation.</p>
  
  <p>Here is the relevant code from the component:</p>
  
  <pre><code>const renderField = ({input, placeholder, type, meta: {touched, error, warning}}) =&gt; (
    &lt;div&gt;
      &lt;input {...input} placeholder={placeholder} type={type} /&gt;
      {touched &amp;&amp;
        ((error &amp;&amp; &lt;span&gt;{error}&lt;/span&gt;) ||
          (warning &amp;&amp; &lt;span&gt;{warning}&lt;/span&gt;)
        )
      }
    &lt;/div&gt;
  )
  
  const required = value =&gt; {
    console.log("required");
    return value ? undefined : 'Required';
  };
  
  const Question = props =&gt; {
    const { handleSubmit, onBlur, question, handleClick } = props;    
    return (
      &lt;div className={`question question-${question.name}`}&gt;
        &lt;form className={props.className} onSubmit={handleSubmit}&gt;
          &lt;div className='question-wrapper'&gt;
            &lt;label className={`single-question-label question-label-${question.name}`}&gt;{question.text}&lt;/label&gt;
            &lt;Field
              component={renderField}
              type={question.type}
              name={question.name}
              placeholder={question.placeholder}
              onBlur={onBlur}
              validate={required}
            /&gt;
          &lt;/div&gt;
        &lt;/form&gt;
      &lt;/div&gt;
    )
  }
  
  export default reduxForm({
    form: 'quiz',
    destroyOnUnmount: false,
    forceUnregisterOnUnmount: true,
  })(Question);
  </code></pre>
  
  <p>When I test it, I see that in the console the <code>UPDATE_SYNC_ERRORS</code> action is being called, and the <code>console.log("required");</code> is also showing up. But when I navigate to the next question, neither on the screen do I see the error message, nor do I see any evidence of it when I inspect the component with DevTools.</p>
  
  <p>I've been following the example on Field-Level Validation shown in the redux-form docs here: <a href="http://redux-form.com/6.7.0/examples/fieldLevelValidation/" rel="nofollow noreferrer">http://redux-form.com/6.7.0/examples/fieldLevelValidation/</a></p>
  
  <p>Any idea what could be causing this? Thanks in advance!</p>