diff --git a/core/config/schema/core.entity.data_types.schema.yml b/core/config/schema/core.entity.data_types.schema.yml
index f0b87ee..36e59fb 100644
--- a/core/config/schema/core.entity.data_types.schema.yml
+++ b/core/config/schema/core.entity.data_types.schema.yml
@@ -18,6 +18,9 @@ entity_field_view_display_base:
     label:
       type: string
       label: 'Label setting machine name'
+    settings:
+      type: sequence
+      label: 'Settings'
 
 # Schema for the base of the form mode display format settings.
 entity_field_form_display_base:
@@ -34,3 +37,6 @@ entity_field_form_display_base:
       label: 'Third party settings'
       sequence:
         - type: entity_form_display.third_party.[%key]
+    settings:
+      type: sequence
+      label: 'Settings'
diff --git a/core/config/schema/core.entity.schema.yml b/core/config/schema/core.entity.schema.yml
index 63a35eb..20a820f 100644
--- a/core/config/schema/core.entity.schema.yml
+++ b/core/config/schema/core.entity.schema.yml
@@ -148,32 +148,14 @@ entity_form_display.field.string_textfield:
 entity_form_display.field.datetime_timestamp:
   type: entity_field_form_display_base
   label: 'Datetime timestamp display format settings'
-  mapping:
-    settings:
-      type: sequence
-      label: 'Settings'
-      sequence:
-        - type: string
 
 entity_form_display.field.boolean_checkbox:
   type: entity_field_form_display_base
   label: 'Boolean checkbox display format settings'
-  mapping:
-    settings:
-      type: sequence
-      label: 'Settings'
-      sequence:
-        - type: string
 
 entity_form_display.field.hidden:
   type: entity_field_form_display_base
   label: '- Hidden - format settings'
-  mapping:
-    settings:
-      type: sequence
-      label: 'Settings'
-      sequence:
-        - type: string
 
 entity_form_display.field.number:
   type: entity_field_form_display_base
@@ -238,29 +220,11 @@ entity_view_display.field.number_integer:
 entity_view_display.field.number_unformatted:
   type: entity_field_view_display_base
   label: 'Number unformatted display format settings'
-  mapping:
-    settings:
-      type: sequence
-      label: 'Settings'
-      sequence:
-        - type: string
 
 entity_view_display.field.uri_link:
   type: entity_field_view_display_base
   label: 'URI as link display format settings'
-  mapping:
-    settings:
-      type: sequence
-      label: 'Settings'
-      sequence:
-        - type: string
 
 entity_view_display.field.timestamp_ago:
   type: entity_field_view_display_base
   label: 'Timestamp ago display format settings'
-  mapping:
-    settings:
-      type: sequence
-      label: 'Settings'
-      sequence:
-        - type: string
diff --git a/core/modules/comment/config/schema/comment.schema.yml b/core/modules/comment/config/schema/comment.schema.yml
index b5bcd86..f27f81a 100644
--- a/core/modules/comment/config/schema/comment.schema.yml
+++ b/core/modules/comment/config/schema/comment.schema.yml
@@ -3,22 +3,10 @@
 entity_view_display.field.comment_default:
   type: entity_field_view_display_base
   label: 'Comment display format settings'
-  mapping:
-    settings:
-      type: sequence
-      label: 'Settings'
-      sequence:
-        - type: string
 
 entity_form_display.field.comment_default:
   type: entity_field_form_display_base
   label: 'Comment display format settings'
-  mapping:
-    settings:
-      type: sequence
-      label: 'Settings'
-      sequence:
-        - type: string
 
 action.configuration.comment_publish_action:
   type: action_configuration_default
diff --git a/core/modules/datetime/config/schema/datetime.schema.yml b/core/modules/datetime/config/schema/datetime.schema.yml
index 58e4cc6..3086164 100644
--- a/core/modules/datetime/config/schema/datetime.schema.yml
+++ b/core/modules/datetime/config/schema/datetime.schema.yml
@@ -41,12 +41,6 @@ entity_view_display.field.datetime_default:
 entity_view_display.field.datetime_plain:
   type: entity_field_view_display_base
   label: 'Datetime plain display format settings'
-  mapping:
-    settings:
-      type: sequence
-      label: 'Settings'
-      sequence:
-        - type: string
 
 entity_form_display.field.datetime_datelist:
   type: entity_field_form_display_base
@@ -69,9 +63,3 @@ entity_form_display.field.datetime_datelist:
 entity_form_display.field.datetime_default:
   type: entity_field_form_display_base
   label: 'Datetime default display format settings'
-  mapping:
-    settings:
-      type: sequence
-      label: 'Settings'
-      sequence:
-        - type: string
diff --git a/core/modules/datetime/src/Tests/DateTimeFieldTest.php b/core/modules/datetime/src/Tests/DateTimeFieldTest.php
index 281e78c..8285a2b 100644
--- a/core/modules/datetime/src/Tests/DateTimeFieldTest.php
+++ b/core/modules/datetime/src/Tests/DateTimeFieldTest.php
@@ -9,6 +9,7 @@
 
 use Drupal\Component\Utility\Unicode;
 use Drupal\Core\Entity\Entity\EntityViewDisplay;
+use Drupal\field\Tests\FieldItemTestBase;
 use Drupal\simpletest\WebTestBase;
 use Drupal\Core\Datetime\DrupalDateTime;
 
@@ -17,7 +18,7 @@
  *
  * @group datetime
  */
-class DateTimeFieldTest extends WebTestBase {
+class DateTimeFieldTest extends FieldItemTestBase {
 
   /**
    * Modules to enable.
diff --git a/core/modules/entity_reference/config/schema/entity_reference.schema.yml b/core/modules/entity_reference/config/schema/entity_reference.schema.yml
index 5404963..22561c9 100644
--- a/core/modules/entity_reference/config/schema/entity_reference.schema.yml
+++ b/core/modules/entity_reference/config/schema/entity_reference.schema.yml
@@ -55,12 +55,6 @@ entity_view_display.field.entity_reference_entity_view:
 entity_view_display.field.entity_reference_entity_id:
   type: entity_field_view_display_base
   label: 'Entity reference entity ID display format settings'
-  mapping:
-    settings:
-      type: sequence
-      label: 'Settings'
-      sequence:
-        - type: string
 
 entity_view_display.field.entity_reference_label:
   type: entity_field_view_display_base
diff --git a/core/modules/field/src/Tests/Email/EmailFieldTest.php b/core/modules/field/src/Tests/Email/EmailFieldTest.php
index 2ce3c46..552cad2 100644
--- a/core/modules/field/src/Tests/Email/EmailFieldTest.php
+++ b/core/modules/field/src/Tests/Email/EmailFieldTest.php
@@ -8,14 +8,14 @@
 namespace Drupal\field\Tests\Email;
 
 use Drupal\Component\Utility\Unicode;
-use Drupal\simpletest\WebTestBase;
+use Drupal\field\Tests\FieldItemTestBase;
 
 /**
  * Tests email field functionality.
  *
  * @group field
  */
-class EmailFieldTest extends WebTestBase {
+class EmailFieldTest extends FieldItemTestBase {
 
   /**
    * Modules to enable.
diff --git a/core/modules/field/src/Tests/FieldItemTestBase.php b/core/modules/field/src/Tests/FieldItemTestBase.php
new file mode 100644
index 0000000..3b707bc
--- /dev/null
+++ b/core/modules/field/src/Tests/FieldItemTestBase.php
@@ -0,0 +1,41 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\field\Tests\FieldItemTestBase.
+ */
+
+namespace Drupal\field\Tests;
+
+use Drupal\simpletest\WebTestBase;
+use Drupal\config\Tests\SchemaCheckTestTrait;
+
+/**
+ * Base class to automatically assert entity display schemas.
+ */
+abstract class FieldItemTestBase extends WebTestBase {
+
+  use SchemaCheckTestTrait;
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function tearDown() {
+    // Assert schemas for all entity view and form displays.
+    $names = array_merge(
+      $this->container->get('config.storage')->listAll('core.entity_view_display.'),
+      $this->container->get('config.storage')->listAll('core.entity_form_display.')
+    );
+
+    $factory = $this->container->get('config.factory');
+    /** @var \Drupal\Core\Config\TypedConfigManagerInterface $typed_config */
+    $typed_config = $this->container->get('config.typed');
+    foreach ($names as $name) {
+      $config = $factory->get($name);
+      $this->assertConfigSchema($typed_config, $name, $config->get());
+    }
+
+    parent::tearDown();
+  }
+
+}
diff --git a/core/modules/field/src/Tests/Number/NumberFieldTest.php b/core/modules/field/src/Tests/Number/NumberFieldTest.php
index ca1fbb0..a1abf41 100644
--- a/core/modules/field/src/Tests/Number/NumberFieldTest.php
+++ b/core/modules/field/src/Tests/Number/NumberFieldTest.php
@@ -8,6 +8,7 @@
 namespace Drupal\field\Tests\Number;
 
 use Drupal\Component\Utility\Unicode;
+use Drupal\field\Tests\FieldItemTestBase;
 use Drupal\simpletest\WebTestBase;
 
 /**
@@ -15,7 +16,7 @@
  *
  * @group field
  */
-class NumberFieldTest extends WebTestBase {
+class NumberFieldTest extends FieldItemTestBase {
 
   /**
    * Modules to enable.
diff --git a/core/modules/field/src/Tests/String/StringFieldTest.php b/core/modules/field/src/Tests/String/StringFieldTest.php
new file mode 100644
index 0000000..faee5a5
--- /dev/null
+++ b/core/modules/field/src/Tests/String/StringFieldTest.php
@@ -0,0 +1,98 @@
+<?php
+
+/**
+ * @file
+ * Definition of \Drupal\field\Tests\String\StringFieldTest.
+ */
+
+namespace Drupal\field\Tests\String;
+
+use Drupal\Component\Utility\Unicode;
+use Drupal\field\Tests\FieldItemTestBase;
+
+/**
+ * Tests the creation of string fields.
+ *
+ * @group text
+ */
+class StringFieldTest extends FieldItemTestBase {
+
+  /**
+   * Modules to enable.
+   *
+   * @var array
+   */
+  public static $modules = array('entity_test');
+
+  protected $web_user;
+
+  protected function setUp() {
+    parent::setUp();
+
+    $this->web_user = $this->drupalCreateUser(array('view test entity', 'administer entity_test content'));
+    $this->drupalLogin($this->web_user);
+  }
+
+  // Test fields.
+
+  /**
+   * Test widgets.
+   */
+  function testTextfieldWidgets() {
+    $this->_testTextfieldWidgets('string', 'string_textfield');
+    $this->_testTextfieldWidgets('string_long', 'string_textarea');
+  }
+
+  /**
+   * Helper function for testTextfieldWidgets().
+   */
+  function _testTextfieldWidgets($field_type, $widget_type) {
+    // Create a field.
+    $field_name = Unicode::strtolower($this->randomMachineName());
+    $field_storage = entity_create('field_storage_config', array(
+      'field_name' => $field_name,
+      'entity_type' => 'entity_test',
+      'type' => $field_type
+    ));
+    $field_storage->save();
+    entity_create('field_config', array(
+      'field_storage' => $field_storage,
+      'bundle' => 'entity_test',
+      'label' => $this->randomMachineName() . '_label',
+    ))->save();
+    entity_get_form_display('entity_test', 'entity_test', 'default')
+      ->setComponent($field_name, array(
+        'type' => $widget_type,
+        'settings' => array(
+          'placeholder' => 'A placeholder on ' . $widget_type,
+        ),
+      ))
+      ->save();
+    entity_get_display('entity_test', 'entity_test', 'full')
+      ->setComponent($field_name)
+      ->save();
+
+    // Display creation form.
+    $this->drupalGet('entity_test/add');
+    $this->assertFieldByName("{$field_name}[0][value]", '', 'Widget is displayed');
+    $this->assertNoFieldByName("{$field_name}[0][format]", '1', 'Format selector is not displayed');
+    $this->assertRaw(format_string('placeholder="A placeholder on !widget_type"', array('!widget_type' => $widget_type)));
+
+    // Submit with some value.
+    $value = $this->randomMachineName();
+    $edit = array(
+      "{$field_name}[0][value]" => $value,
+    );
+    $this->drupalPostForm(NULL, $edit, t('Save'));
+    preg_match('|entity_test/manage/(\d+)|', $this->url, $match);
+    $id = $match[1];
+    $this->assertText(t('entity_test @id has been created.', array('@id' => $id)), 'Entity was created');
+
+    // Display the entity.
+    $entity = entity_load('entity_test', $id);
+    $display = entity_get_display($entity->getEntityTypeId(), $entity->bundle(), 'full');
+    $content = $display->build($entity);
+    $this->drupalSetContent(drupal_render($content));
+    $this->assertText($value, 'Filtered tags are not displayed');
+  }
+}
diff --git a/core/modules/file/config/schema/file.schema.yml b/core/modules/file/config/schema/file.schema.yml
index cd21f38..0babe38 100644
--- a/core/modules/file/config/schema/file.schema.yml
+++ b/core/modules/file/config/schema/file.schema.yml
@@ -70,43 +70,18 @@ field.file.field_settings:
 entity_view_display.field.file_default:
   type: entity_field_view_display_base
   label: 'Generic file format settings'
-  mapping:
-    settings:
-      type: sequence
-      label: 'Settings'
-      sequence:
-        - type: string
 
 entity_view_display.field.file_rss_enclosure:
   type: entity_field_view_display_base
   label: 'RSS enclosure format settings'
-  mapping:
-    settings:
-      type: sequence
-      label: 'Settings'
-      sequence:
-        - type: string
 
 entity_view_display.field.file_table:
   type: entity_field_view_display_base
   label: 'Table of files format settings'
-  mapping:
-    settings:
-      type: sequence
-      label: 'Settings'
-      sequence:
-        - type: string
 
 entity_view_display.field.file_url_plain:
   type: entity_field_view_display_base
   label: 'URL to file format settings'
-  mapping:
-    settings:
-      type: sequence
-      label: 'Settings'
-      sequence:
-        - type: string
-
 
 entity_form_display.field.file_generic:
   type: entity_field_form_display_base
diff --git a/core/modules/image/config/schema/image.schema.yml b/core/modules/image/config/schema/image.schema.yml
index f0db0d5..33e8a90 100644
--- a/core/modules/image/config/schema/image.schema.yml
+++ b/core/modules/image/config/schema/image.schema.yml
@@ -137,12 +137,6 @@ field.image.value:
 entity_view_display.field.image:
   type: entity_field_view_display_base
   label: 'Image field display format settings'
-  mapping:
-    settings:
-      type: sequence
-      label: 'Format settings'
-      sequence:
-        - type: string
 
 entity_form_display.field.image_image:
   type: entity_field_form_display_base
diff --git a/core/modules/image/src/Tests/ImageFieldTestBase.php b/core/modules/image/src/Tests/ImageFieldTestBase.php
index 33e7fc1..554954b 100644
--- a/core/modules/image/src/Tests/ImageFieldTestBase.php
+++ b/core/modules/image/src/Tests/ImageFieldTestBase.php
@@ -7,6 +7,7 @@
 
 namespace Drupal\image\Tests;
 
+use Drupal\field\Tests\FieldItemTestBase;
 use Drupal\simpletest\WebTestBase;
 
 /**
@@ -25,7 +26,7 @@
 /**
  * This class provides methods specifically for testing Image's field handling.
  */
-abstract class ImageFieldTestBase extends WebTestBase {
+abstract class ImageFieldTestBase extends FieldItemTestBase {
 
   /**
    * Modules to enable.
diff --git a/core/modules/options/config/schema/options.schema.yml b/core/modules/options/config/schema/options.schema.yml
index 03cb81f..f0d444a 100644
--- a/core/modules/options/config/schema/options.schema.yml
+++ b/core/modules/options/config/schema/options.schema.yml
@@ -114,39 +114,15 @@ field.list_string.value:
 entity_view_display.field.list_default:
   type: entity_field_view_display_base
   label: 'Options list default display settings'
-  mapping:
-    settings:
-      type: sequence
-      label: 'Settings'
-      sequence:
-        - type: string
 
 entity_view_display.field.list_key:
   type: entity_field_view_display_base
   label: 'Key format settings'
-  mapping:
-    settings:
-      type: sequence
-      label: 'Settings'
-      sequence:
-        - type: string
 
 entity_form_display.field.options_buttons:
   type: entity_field_form_display_base
   label: 'Check boxes/radio buttons format settings'
-  mapping:
-    settings:
-      type: sequence
-      label: 'Settings'
-      sequence:
-        - type: string
 
 entity_form_display.field.options_select:
   type: entity_field_form_display_base
   label: 'Select list format settings'
-  mapping:
-    settings:
-      type: sequence
-      label: 'Settings'
-      sequence:
-        - type: string
diff --git a/core/modules/path/config/schema/path.schema.yml b/core/modules/path/config/schema/path.schema.yml
index f595e4b..ebed69c 100644
--- a/core/modules/path/config/schema/path.schema.yml
+++ b/core/modules/path/config/schema/path.schema.yml
@@ -3,6 +3,3 @@
 entity_form_display.field.path:
   type: entity_field_form_display_base
   label: 'Link format settings'
-  mapping:
-    settings:
-      type: sequence
diff --git a/core/modules/taxonomy/config/schema/taxonomy.schema.yml b/core/modules/taxonomy/config/schema/taxonomy.schema.yml
index 579f673..e9aed2b 100644
--- a/core/modules/taxonomy/config/schema/taxonomy.schema.yml
+++ b/core/modules/taxonomy/config/schema/taxonomy.schema.yml
@@ -94,12 +94,6 @@ entity_view_display.field.taxonomy_term_reference_rss_category:
 entity_view_display.field.taxonomy_term_reference_link:
   type: entity_field_view_display_base
   label: 'Taxonomy format settings'
-  mapping:
-    settings:
-      type: sequence
-      label: 'Settings'
-      sequence:
-        - type: string
 
 entity_form_display.field.taxonomy_autocomplete:
   type: entity_field_form_display_base
diff --git a/core/modules/text/config/schema/text.schema.yml b/core/modules/text/config/schema/text.schema.yml
index f472aec..f211cbf 100644
--- a/core/modules/text/config/schema/text.schema.yml
+++ b/core/modules/text/config/schema/text.schema.yml
@@ -93,12 +93,6 @@ field.text_with_summary.value:
 entity_view_display.field.text_default:
   type: entity_field_view_display_base
   label: 'Formatted text default display format settings'
-  mapping:
-    settings:
-      type: sequence
-      label: 'Settings'
-      sequence:
-        - type: string
 
 entity_view_display.field.text_summary_or_trimmed:
   type: entity_field_view_display_base
diff --git a/core/modules/text/src/Tests/TextFieldTest.php b/core/modules/text/src/Tests/TextFieldTest.php
index e771af9..e8ece1f 100644
--- a/core/modules/text/src/Tests/TextFieldTest.php
+++ b/core/modules/text/src/Tests/TextFieldTest.php
@@ -9,31 +9,21 @@
 
 use Drupal\Component\Utility\String;
 use Drupal\Component\Utility\Unicode;
-use Drupal\simpletest\WebTestBase;
+use Drupal\field\Tests\String\StringFieldTest;
 
 /**
  * Tests the creation of text fields.
  *
  * @group text
  */
-class TextFieldTest extends WebTestBase {
-
-  /**
-   * Modules to enable.
-   *
-   * @var array
-   */
-  public static $modules = array('entity_test');
+class TextFieldTest extends StringFieldTest {
 
   protected $admin_user;
-  protected $web_user;
 
   protected function setUp() {
     parent::setUp();
 
     $this->admin_user = $this->drupalCreateUser(array('administer filters'));
-    $this->web_user = $this->drupalCreateUser(array('view test entity', 'administer entity_test content'));
-    $this->drupalLogin($this->web_user);
   }
 
   // Test fields.
@@ -82,59 +72,6 @@ function testTextfieldWidgets() {
   }
 
   /**
-   * Helper function for testTextfieldWidgets().
-   */
-  function _testTextfieldWidgets($field_type, $widget_type) {
-    // Create a field.
-    $field_name = Unicode::strtolower($this->randomMachineName());
-    $field_storage = entity_create('field_storage_config', array(
-      'field_name' => $field_name,
-      'entity_type' => 'entity_test',
-      'type' => $field_type
-    ));
-    $field_storage->save();
-    entity_create('field_config', array(
-      'field_storage' => $field_storage,
-      'bundle' => 'entity_test',
-      'label' => $this->randomMachineName() . '_label',
-    ))->save();
-    entity_get_form_display('entity_test', 'entity_test', 'default')
-      ->setComponent($field_name, array(
-        'type' => $widget_type,
-        'settings' => array(
-          'placeholder' => 'A placeholder on ' . $widget_type,
-        ),
-      ))
-      ->save();
-    entity_get_display('entity_test', 'entity_test', 'full')
-      ->setComponent($field_name)
-      ->save();
-
-    // Display creation form.
-    $this->drupalGet('entity_test/add');
-    $this->assertFieldByName("{$field_name}[0][value]", '', 'Widget is displayed');
-    $this->assertNoFieldByName("{$field_name}[0][format]", '1', 'Format selector is not displayed');
-    $this->assertRaw(format_string('placeholder="A placeholder on !widget_type"', array('!widget_type' => $widget_type)));
-
-    // Submit with some value.
-    $value = $this->randomMachineName();
-    $edit = array(
-      "{$field_name}[0][value]" => $value,
-    );
-    $this->drupalPostForm(NULL, $edit, t('Save'));
-    preg_match('|entity_test/manage/(\d+)|', $this->url, $match);
-    $id = $match[1];
-    $this->assertText(t('entity_test @id has been created.', array('@id' => $id)), 'Entity was created');
-
-    // Display the entity.
-    $entity = entity_load('entity_test', $id);
-    $display = entity_get_display($entity->getEntityTypeId(), $entity->bundle(), 'full');
-    $content = $display->build($entity);
-    $this->drupalSetContent(drupal_render($content));
-    $this->assertText($value, 'Filtered tags are not displayed');
-  }
-
-  /**
    * Test widgets + 'formatted_text' setting.
    */
   function testTextfieldWidgetsFormatted() {