Support RDFa output in telephone field formatter

Basic implementation of telephone field formatter test. Working with Kay @rdfcodesprint.

For manual testing, the field mapping needs to be created manually by editing the rdf.mapping.node.[content type].yml file by copying a field mapping (last 3 lines of the file) and changing the schema.

Combined the asserts into one test.

This code handles the issue scor mentioned in #3:

      if (!empty($item->_attributes)) {
        $element[$delta]['#options'] += array('attributes' => array());
        $element[$delta]['#options']['attributes'] += $item->_attributes;
        // Unset field item attributes since they have been included in the
        // formatter output and should not be rendered in the field template.
        unset($item->_attributes);
      }

We still need a test for this.

I need to fix the last patch, since some of the email formatter code got mixed in.

Also, I'm reading this issue: #1778122: Enable modules to inject attributes into field formatters, so that RDF attributes get output to better understand how to set up the test the attributes issue from comment #3.

Fixed up the patch.

I think we need a test that asserts that rdf reads the number from the href and not the value from the div ("Call me maybe.") I am not sure how we would set the title for the telephone field in a test. I think it can be done in the entity_create() or by setting $this->entity->{$this->fieldName}->title?

    // Set up test values.
    $this->testValue = '555-555-5555';
    $this->entity = entity_create('entity_test', array());
    $this->entity->{$this->fieldName}->value = $this->testValue;

Implemented the suggestion in #11.

I created a test that passes. But, do I need to use datatype? I have it commented out below.

<?php
   $formatter = array(
      'type' => 'telephone_link',
      'settings' => array('title' => 'Contact us'),
    );
    $expected_rdf_value = array(
      'value' => 'tel:' . $this->testValue,
      'type' => 'uri',
      /*'datatype' => 'schema:telephone',*/
    );
    // Tests the telephone link formatter with custom title.
    $this->assertFormatterRdfa($formatter, 'http://schema.org/telephone', $expected_rdf_value);
?>

Added a test and rerolled for the updated assertFormatterRdfa().

Committed 85392bf and pushed to 8.x. Thanks!

diff --git a/core/modules/rdf/lib/Drupal/rdf/Tests/Field/TelephoneFieldRdfaTest.php b/core/modules/rdf/lib/Drupal/rdf/Tests/Field/TelephoneFieldRdfaTest.php
index 0ab144f..32d6825 100644
--- a/core/modules/rdf/lib/Drupal/rdf/Tests/Field/TelephoneFieldRdfaTest.php
+++ b/core/modules/rdf/lib/Drupal/rdf/Tests/Field/TelephoneFieldRdfaTest.php
@@ -6,14 +6,19 @@
 
 namespace Drupal\rdf\Tests\Field;
 
-use Drupal\rdf\Tests\Field\FieldRdfaTestBase;
-
 /**
  * Tests the placement of RDFa in telephone field formatters.
  */
 class TelephoneFieldRdfaTest extends FieldRdfaTestBase {
 
   /**
+   * A test value for the telephone field.
+   *
+   * @var string
+   */
+  protected $testValue;
+
+  /**
    * {@inheritdoc}
    */
   protected $fieldType = 'telephone';

Fixed during commit. The use is unnecessary since the classes are in the same namespace. Class properties shouldn't really be declared dynamically.