diff --git a/core/tests/Drupal/Tests/Core/Entity/EntityStorageBaseTest.php b/core/tests/Drupal/Tests/Core/Entity/EntityStorageBaseTest.php
new file mode 100644
index 0000000..b51d671
--- /dev/null
+++ b/core/tests/Drupal/Tests/Core/Entity/EntityStorageBaseTest.php
@@ -0,0 +1,168 @@
+<?php
+
+namespace Drupal\Tests\Core\Entity;
+
+use Drupal\Tests\UnitTestCase;
+
+/**
+ * @coversDefaultClass \Drupal\Core\Entity\EntityStorageBase
+ * @group Entity
+ */
+class EntityStorageBaseTest extends UnitTestCase {
+
+  /**
+   * Generate a mocked entity object.
+   *
+   * @param string $id
+   *   ID value for this entity.
+   *
+   * @return \Drupal\Core\Entity\EntityInterface|\PHPUnit_Framework_MockObject_MockObject
+   *   The mocked entity.
+   */
+  public function generateEntityInterface($id) {
+    $mock_entity = $this->getMockBuilder('\Drupal\Core\Entity\EntityInterface')
+      ->setMethods(['id'])
+      ->getMockForAbstractClass();
+    $mock_entity->expects($this->any())
+      ->method('id')
+      ->willReturn((string) $id);
+    return $mock_entity;
+  }
+
+  /**
+   * Data provider for testLoad().
+   *
+   * @return array
+   *   - Expected output of load().
+   *   - A fixture of entities to query against. Suitable return value for
+   *     loadMultiple().
+   *   - The ID we'll query.
+   */
+  public function providerLoad() {
+    $data = [];
+
+    // Data set for a matching value.
+    $entity = $this->generateEntityInterface('1');
+    $data['matching-value'] = [$entity, ['1' => $entity], '1'];
+
+    // Data set for no matching value.
+    $data['no-matching-value'] = [NULL, [], '0'];
+
+    return $data;
+  }
+
+  /**
+   * @covers ::load
+   *
+   * @dataProvider providerLoad
+   */
+  public function testLoad($expected, $entity_fixture, $query) {
+    $mock_base = $this->getMockBuilder('\Drupal\Core\Entity\EntityStorageBase')
+      ->disableOriginalConstructor()
+      ->setMethods(['loadMultiple'])
+      ->getMockForAbstractClass();
+
+    // load() always calls loadMultiple().
+    $mock_base->expects($this->once())
+      ->method('loadMultiple')
+      ->with([$query])
+      ->willReturn($entity_fixture);
+
+    $this->assertEquals($expected, $mock_base->load($query));
+  }
+
+  /**
+   * @return array
+   *   - The expected result.
+   *   - Results for doLoadMultiple(), called internally by loadMultiple().
+   *   - The query, an array of IDs.
+   */
+  public function providerLoadMultiple() {
+    // Create a fixture of entity objects.
+    $fixture = [];
+    foreach (range(1, 10) as $index) {
+      $fixture[(string) $index] = $this->generateEntityInterface($index);
+    }
+
+    $data = [];
+
+    // Data set for NULL ID parameter.
+    $data['null-id-parameter'] = [$fixture, $fixture, NULL];
+
+    // Data set for no results.
+    $data['no-results'] = [[], [], ['11']];
+
+    // Data set for 0 results for multiple IDs.
+    $data['no-results-multiple-ids'] = [[], [], ['11', '12', '13']];
+
+    // Data set for 1 result for 1 ID.
+    $data['1-result-for-1-id'] = [
+      ['1' => $fixture['1']],
+      ['1' => $fixture['1']],
+      ['1']
+    ];
+
+    // Data set for results for all IDs.
+    $ids = ['1', '2', '3'];
+    foreach ($ids as $id) {
+      $expectation[$id] = $fixture[$id];
+      $load_multiple[$id] = $fixture[$id];
+    }
+    $data['results-for-all-ids'] = [$expectation, $load_multiple, $ids];
+
+    // Data set for partial results for multiple IDs.
+    $ids = ['1', '2', '3'];
+    foreach ($ids as $id) {
+      $expectation[$id] = $fixture[$id];
+      $load_multiple[$id] = $fixture[$id];
+    }
+    $ids = array_merge($ids, ['11', '12']);
+    $data['partial-results-for-multiple-ids'] = [$expectation, $load_multiple, $ids];
+
+    return $data;
+  }
+
+  /**
+   * Test loadMultiple().
+   *
+   * Does not cover statically-cached results.
+   *
+   * @covers ::loadMultiple
+   *
+   * @dataProvider providerLoadMultiple
+   */
+  public function testLoadMultiple($expected, $load_multiple, $query) {
+    // Make our EntityStorageBase mock.
+    $mock_base = $this->getMockBuilder('\Drupal\Core\Entity\EntityStorageBase')
+      ->disableOriginalConstructor()
+      ->setMethods(['doLoadMultiple', 'postLoad'])
+      ->getMockForAbstractClass();
+
+    // For all non-cached queries, we call doLoadMultiple().
+    $mock_base->expects($this->once())
+      ->method('doLoadMultiple')
+      ->with($query)
+      ->willReturn($load_multiple);
+
+    // Make our EntityTypeInterface mock so that we can turn off static caching.
+    $mock_entity_type = $this->getMockBuilder('\Drupal\Core\Entity\EntityTypeInterface')
+      ->setMethods(['isStaticallyCacheable'])
+      ->getMockForAbstractClass();
+    // Disallow caching.
+    $mock_entity_type->expects($this->any())
+      ->method('isStaticallyCacheable')
+      ->willReturn(FALSE);
+    // Add the EntityTypeInterface to the storage object.
+    $ref_entity_type = new \ReflectionProperty($mock_base, 'entityType');
+    $ref_entity_type->setAccessible(TRUE);
+    $ref_entity_type->setValue($mock_base, $mock_entity_type);
+
+    // Set up expectations for postLoad(), which we only call if there are
+    // results from loadMultiple().
+    $mock_base->expects($this->exactly(empty($load_multiple) ? 0 : 1))
+      ->method('postLoad');
+
+    $this->assertEquals($expected, $mock_base->loadMultiple($query));
+  }
+
+}