tests/src/Functional/ExternalNormalizersTest.php | 70 ++++++++++++------------
 1 file changed, 36 insertions(+), 34 deletions(-)

diff --git a/tests/src/Functional/ExternalNormalizersTest.php b/tests/src/Functional/ExternalNormalizersTest.php
index 9694a9a..953e2c9 100644
--- a/tests/src/Functional/ExternalNormalizersTest.php
+++ b/tests/src/Functional/ExternalNormalizersTest.php
@@ -21,6 +21,21 @@ use Drupal\user\RoleInterface;
 class ExternalNormalizersTest extends BrowserTestBase {
 
   /**
+   * The original value for the test field.
+   *
+   * @var string
+   */
+  const VALUE_ORIGINAL = 'Llamas are super awesome!';
+
+  /**
+   * The expected overridden value for the test field.
+   *
+   * @see \Drupal\jsonapi_test_field_type\Normalizer\StringNormalizer
+   * @see \Drupal\jsonapi_test_data_type\Normalizer\StringNormalizer
+   */
+  const VALUE_OVERRIDDEN = 'Llamas are NOT awesome!';
+
+  /**
    * {@inheritdoc}
    */
   protected static $modules = [
@@ -29,6 +44,13 @@ class ExternalNormalizersTest extends BrowserTestBase {
   ];
 
   /**
+   * The test entity.
+   *
+   * @var \Drupal\entity_test\Entity\EntityTest
+   */
+  protected $entity;
+
+  /**
    * {@inheritdoc}
    */
   public function setUp() {
@@ -67,22 +89,13 @@ class ExternalNormalizersTest extends BrowserTestBase {
    * @see jsonapi.normalizers
    */
   public function testFormatAgnosticFieldTypeNormalizers() {
-    $value = 'Llamas are super awesome!';
-
-    $entity_test = EntityTest::create([
-      'name' => 'Llama',
-      'type' => 'entity_test',
-      'field_test' => $value,
-    ]);
-    $entity_test->save();
-
     // Asserts the entity contains the value we set.
-    $this->assertSame($value, $entity_test->field_test->value);
+    $this->assertSame(static::VALUE_ORIGINAL, $this->entity->field_test->value);
 
     // Asserts normalizing the entity using core's 'serializer' service DOES
     // yield the value we set.
-    $core_normalization = $this->container->get('serializer')->normalize($entity_test);
-    $this->assertSame('Llamas are super awesome!', $core_normalization['field_test'][0]['value']);
+    $core_normalization = $this->container->get('serializer')->normalize($this->entity);
+    $this->assertSame(static::VALUE_ORIGINAL, $core_normalization['field_test'][0]['value']);
 
     // Install test module that contains a high-priority alternative normalizer:
     // \Drupal\jsonapi_test_field_type\Normalizer\StringNormalizer::normalize().
@@ -91,18 +104,17 @@ class ExternalNormalizersTest extends BrowserTestBase {
 
     // Asserts normalizing the entity using core's 'serializer' service DOES NOT
     // ANYMORE yield the value we set.
-    $core_normalization = $this->container->get('serializer')->normalize($entity_test);
-    $this->assertNotSame($value, $core_normalization['field_test'][0]['value']);
-    $this->assertSame('Llamas are NOT awesome!', $core_normalization['field_test'][0]['value']);
+    $core_normalization = $this->container->get('serializer')->normalize($this->entity);
+    $this->assertSame(static::VALUE_OVERRIDDEN, $core_normalization['field_test'][0]['value']);
 
     // Asserts that this does NOT affect the JSON API normalization.
     // @todo Remove line below in favor of commented line in https://www.drupal.org/project/jsonapi/issues/2878463.
-    $url = Url::fromRoute('jsonapi.entity_test--entity_test.individual', ['entity_test'=> $entity_test->uuid()]);
+    $url = Url::fromRoute('jsonapi.entity_test--entity_test.individual', ['entity_test'=> $this->entity->uuid()]);
     /* $url = $this->entity->toUrl('jsonapi'); */
     $client = $this->getSession()->getDriver()->getClient()->getClient();
     $response = $client->request('GET', $url->setAbsolute(TRUE)->toString());
     $document = Json::decode((string) $response->getBody());
-    $this->assertSame($value, $document['data']['attributes']['field_test']);
+    $this->assertSame(static::VALUE_ORIGINAL, $document['data']['attributes']['field_test']);
   }
 
   /**
@@ -111,22 +123,13 @@ class ExternalNormalizersTest extends BrowserTestBase {
    * @see jsonapi.normalizers
    */
   public function testFormatAgnosticDataTypeNormalizers() {
-    $value = 'Llamas are super awesome!';
-
-    $entity_test = EntityTest::create([
-      'name' => 'Llama',
-      'type' => 'entity_test',
-      'field_test' => $value,
-    ]);
-    $entity_test->save();
-
     // Asserts the entity contains the value we set.
-    $this->assertSame($value, $entity_test->field_test->value);
+    $this->assertSame(static::VALUE_ORIGINAL, $this->entity->field_test->value);
 
     // Asserts normalizing the entity using core's 'serializer' service DOES
     // yield the value we set.
-    $core_normalization = $this->container->get('serializer')->normalize($entity_test);
-    $this->assertSame('Llamas are super awesome!', $core_normalization['field_test'][0]['value']);
+    $core_normalization = $this->container->get('serializer')->normalize($this->entity);
+    $this->assertSame(static::VALUE_ORIGINAL, $core_normalization['field_test'][0]['value']);
 
     // Install test module that contains a high-priority alternative normalizer:
     // \Drupal\jsonapi_test_field_type\Normalizer\StringNormalizer::normalize().
@@ -135,18 +138,17 @@ class ExternalNormalizersTest extends BrowserTestBase {
 
     // Asserts normalizing the entity using core's 'serializer' service DOES NOT
     // ANYMORE yield the value we set.
-    $core_normalization = $this->container->get('serializer')->normalize($entity_test);
-    $this->assertNotSame($value, $core_normalization['field_test'][0]['value']);
-    $this->assertSame('Llamas are NOT awesome!', $core_normalization['field_test'][0]['value']);
+    $core_normalization = $this->container->get('serializer')->normalize($this->entity);
+    $this->assertSame(static::VALUE_OVERRIDDEN, $core_normalization['field_test'][0]['value']);
 
     // Asserts that this DOES affect the JSON API normalization.
     // @todo Remove line below in favor of commented line in https://www.drupal.org/project/jsonapi/issues/2878463.
-    $url = Url::fromRoute('jsonapi.entity_test--entity_test.individual', ['entity_test'=> $entity_test->uuid()]);
+    $url = Url::fromRoute('jsonapi.entity_test--entity_test.individual', ['entity_test'=> $this->entity->uuid()]);
     /* $url = $this->entity->toUrl('jsonapi'); */
     $client = $this->getSession()->getDriver()->getClient()->getClient();
     $response = $client->request('GET', $url->setAbsolute(TRUE)->toString());
     $document = Json::decode((string) $response->getBody());
-    $this->assertSame('Llamas are NOT awesome!', $document['data']['attributes']['field_test']);
+    $this->assertSame(static::VALUE_OVERRIDDEN, $document['data']['attributes']['field_test']);
   }
 
 }
\ No newline at end of file