Issue #2938799 by claudiu.cristea: Provide the timestamp scalar data type

core/config/schema/core.data_types.schema.yml

@@ -28,6 +28,9 @@ email:
 integer:
   label: 'Integer'
   class: '\Drupal\Core\TypedData\Plugin\DataType\IntegerData'
+timestamp:
+  label: 'Timestamp'
+  class: '\Drupal\Core\TypedData\Plugin\DataType\Timestamp'
 float:
   label: 'Float'
   class: '\Drupal\Core\TypedData\Plugin\DataType\FloatData'

core/modules/field/tests/modules/field_timestamp_test/config/install/field.field.entity_test.entity_test.timestamp.yml

+langcode: en
+status: true
+dependencies:
+  config:
+    - field.storage.entity_test.timestamp
+id: entity_test.entity_test.timestamp
+field_name: timestamp
+entity_type: entity_test
+bundle: entity_test
+label: 'Time stamp'
+description: ''
+required: false
+translatable: false
+default_value:
+  -
+    value: 1514847537
+default_value_callback: ''
+settings: {  }
+field_type: timestamp

core/modules/field/tests/modules/field_timestamp_test/config/install/field.storage.entity_test.timestamp.yml

+langcode: en
+status: true
+dependencies:
+  module:
+    - entity_test
+id: node.timestamp
+field_name: timestamp
+entity_type: entity_test
+type: timestamp
+settings: {  }
+module: core
+locked: false
+cardinality: 1
+translatable: true
+indexes: {  }
+persist_with_no_fields: false
+custom_storage: false

core/modules/field/tests/modules/field_timestamp_test/field_timestamp_test.info.yml

+name: 'Field Timestamp Test'
+type: module
+description: 'Support module for the Timestamp field item test.'
+core: 8.x
+package: Testing
+version: VERSION
+dependencies:
+  - entity_test
+  - field

core/tests/Drupal/KernelTests/Core/Datetime/TimestampSchemaTest.php

+<?php
+
+namespace Drupal\KernelTests\Core\Datetime;
+
+use Drupal\KernelTests\KernelTestBase;
+
+/**
+ * Tests timestamp schema.
+ *
+ * @group Common
+ */
+class TimestampSchemaTest extends KernelTestBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  protected static $modules = ['entity_test', 'field', 'field_timestamp_test'];
+
+  /**
+   * Tests if the timestamp field schema is validated.
+   */
+  public function testTimestampSchema() {
+    $this->installConfig(['field_timestamp_test']);
+    // Make at least an assertion.
+    $this->assertTrue(TRUE);
+  }
+
+}