class StorageTestBase

abstract class StorageTestBase extends KernelTestBase {
    
    /**
     * An array of random stdClass objects.
     *
     * @var array
     */
    protected $objects = [];
    
    /**
     * An array of data collection labels.
     *
     * @var array
     */
    protected $collections = [];
    
    /**
     * Whether we are using an expirable key/value store.
     *
     * @var bool
     */
    protected $factory = 'keyvalue';
    
    /**
     * {@inheritdoc}
     */
    protected function setUp() : void {
        parent::setUp();
        // Define two data collections,
        $this->collections = [
            0 => 'zero',
            1 => 'one',
        ];
        // Create several objects for testing.
        for ($i = 0; $i <= 5; $i++) {
            $this->objects[$i] = $this->randomObject();
        }
    }
    
    /**
     * Tests CRUD operations.
     */
    public function testCRUD() : void {
        $stores = $this->createStorage();
        // Verify that each store returns its own collection name.
        $this->assertSame($this->collections[0], $stores[0]->getCollectionName());
        $this->assertSame($this->collections[1], $stores[1]->getCollectionName());
        // Verify that an item can be stored.
        $stores[0]->set('foo', $this->objects[0]);
        $this->assertTrue($stores[0]->has('foo'));
        $this->assertEquals($this->objects[0], $stores[0]->get('foo'));
        // Verify that the other collection is not affected.
        $this->assertFalse($stores[1]->has('foo'));
        $this->assertNull($stores[1]->get('foo'));
        // Verify that an item can be updated.
        $stores[0]->set('foo', $this->objects[1]);
        $this->assertEquals($this->objects[1], $stores[0]->get('foo'));
        // Verify that the other collection is still not affected.
        $this->assertNull($stores[1]->get('foo'));
        // Verify that a collection/name pair is unique.
        $stores[1]->set('foo', $this->objects[2]);
        $this->assertEquals($this->objects[1], $stores[0]->get('foo'));
        $this->assertEquals($this->objects[2], $stores[1]->get('foo'));
        // Verify that an item can be deleted.
        $stores[0]->delete('foo');
        $this->assertFalse($stores[0]->has('foo'));
        $this->assertNull($stores[0]->get('foo'));
        // Verify that the other collection is not affected.
        $this->assertTrue($stores[1]->has('foo'));
        $this->assertEquals($this->objects[2], $stores[1]->get('foo'));
        $stores[1]->delete('foo');
        $this->assertNull($stores[1]->get('foo'));
        // Verify that multiple items can be stored.
        $values = [
            'foo' => $this->objects[3],
            'bar' => $this->objects[4],
        ];
        $stores[0]->setMultiple($values);
        // Verify that multiple items can be retrieved.
        $result = $stores[0]->getMultiple([
            'foo',
            'bar',
        ]);
        foreach ($values as $j => $value) {
            $this->assertEquals($value, $result[$j]);
        }
        // Verify that the other collection was not affected.
        $this->assertNull($stores[1]->get('foo'));
        $this->assertNull($stores[1]->get('bar'));
        // Verify that all items in a collection can be retrieved.
        // Ensure that an item with the same name exists in the other collection.
        $stores[1]->set('foo', $this->objects[5]);
        // Not using assertSame(), since the order is not defined for getAll().
        $this->assertEquals($values, $stores[0]->getAll());
        // Verify that all items in the other collection are different.
        $result = $stores[1]->getAll();
        $this->assertEquals([
            'foo' => $this->objects[5],
        ], $result);
        // Verify that multiple items can be deleted.
        $stores[0]->deleteMultiple(array_keys($values));
        $this->assertNull($stores[0]->get('foo'));
        $this->assertNull($stores[0]->get('bar'));
        $this->assertEmpty($stores[0]->getMultiple([
            'foo',
            'bar',
        ]));
        // Verify that deleting no items does not cause an error.
        $stores[0]->deleteMultiple([]);
        // Verify that the item in the other collection still exists.
        $this->assertEquals($this->objects[5], $stores[1]->get('foo'));
    }
    
    /**
     * Tests expected behavior for non-existing keys.
     */
    public function testNonExistingKeys() : void {
        $stores = $this->createStorage();
        // Verify that a non-existing key returns NULL as value.
        $this->assertNull($stores[0]->get('foo'));
        // Verify that a non-existing key with a default returns the default.
        $this->assertSame('bar', $stores[0]->get('foo', 'bar'));
        // Verify that a FALSE value can be stored.
        $stores[0]->set('foo', FALSE);
        $this->assertFalse($stores[0]->get('foo'));
        // Verify that a deleted key returns NULL as value.
        $stores[0]->delete('foo');
        $this->assertNull($stores[0]->get('foo'));
        // Verify that a non-existing key is not returned when getting multiple keys.
        $stores[0]->set('bar', 'baz');
        $values = $stores[0]->getMultiple([
            'foo',
            'bar',
        ]);
        $this->assertFalse(isset($values['foo']), "Key 'foo' not found.");
        $this->assertSame('baz', $values['bar']);
    }
    
    /**
     * Tests the setIfNotExists() method.
     */
    public function testSetIfNotExists() : void {
        $stores = $this->createStorage();
        $key = $this->randomMachineName();
        // Test that setIfNotExists() succeeds only the first time.
        for ($i = 0; $i <= 1; $i++) {
            // setIfNotExists() should be TRUE the first time (when $i is 0) and
            // FALSE the second time (when $i is 1).
            $this->assertEquals(!$i, $stores[0]->setIfNotExists($key, $this->objects[$i]));
            $this->assertEquals($this->objects[0], $stores[0]->get($key));
            // Verify that the other collection is not affected.
            $this->assertNull($stores[1]->get($key));
        }
        // Remove the item and try to set it again.
        $stores[0]->delete($key);
        $stores[0]->setIfNotExists($key, $this->objects[1]);
        // This time it should succeed.
        $this->assertEquals($this->objects[1], $stores[0]->get($key));
        // Verify that the other collection is still not affected.
        $this->assertNull($stores[1]->get($key));
    }
    
    /**
     * Tests the rename operation.
     */
    public function testRename() : void {
        $stores = $this->createStorage();
        $store = $stores[0];
        $store->set('old', 'thing');
        $this->assertSame('thing', $store->get('old'));
        $store->rename('old', 'new');
        $this->assertSame('thing', $store->get('new'));
        $this->assertNull($store->get('old'));
    }
    
    /**
     * Tests the rename operation.
     */
    public function testRenameNoChange() : void {
        $stores = $this->createStorage();
        $store = $stores[0];
        $store->set('old', 'thing');
        $this->assertSame($store->get('old'), 'thing');
        $store->rename('old', 'old');
        $this->assertSame($store->get('old'), 'thing');
    }
    
    /**
     * Creates storage objects for each collection defined for this class.
     *
     * Storing the storage objects in a class member variable causes a fatal
     * exception in DatabaseStorageExpirableTest, because in that situation
     * garbage collection is not triggered until the test class itself is
     * destructed, after tearDown() has deleted the database tables. Instead,
     * create the storage objects locally in each test using this method.
     *
     * @see \Drupal\system\Tests\KeyValueStore\DatabaseStorageExpirable
     * @see \Drupal\Core\KeyValueStore\DatabaseStorageExpirable::garbageCollection()
     */
    protected function createStorage() {
        $stores = [];
        foreach ($this->collections as $i => $collection) {
            $stores[$i] = $this->container
                ->get($this->factory)
                ->get($collection);
        }
        return $stores;
    }

}