Issue #1998582 by damiankloip, brantwynn, dawehner: Auto-generate machine_name() for Views Blocks using [viewname]_[displayname] rather than forcing manual entry.

core/modules/block/lib/Drupal/block/Tests/Views/DisplayBlockTest.php

@@ -108,6 +108,25 @@ class DisplayBlockTest extends ViewTestBase {
     $this->drupalGet('admin/structure/block/add/views_block:test_view_block-block_1/' . $default_theme);
     $elements = $this->xpath('//input[@name="label"]');
     $this->assertTrue(empty($elements), 'The label field is not found for Views blocks.');
+    // Test that that machine name field is hidden from display and has been
+    // saved as expected from the default value.
+    $this->assertNoFieldById('edit-machine-name', 'stark.views_block__test_view_block_1', 'The machine name is hidden on the views block form.');
+    // Save the block.
+    $this->drupalPost(NULL, array(), t('Save block'));
+    $storage = $this->container->get('plugin.manager.entity')->getStorageController('block');
+    $blocks = $storage->load(array('stark.views_block__test_view_block_block_1'));
+    // This will only return a result if our new block has been created with the
+    // expected machine name.
+    $this->assertTrue(!empty($blocks), 'The expected block was loaded.');
+
+    for ($i = 2; $i <= 3; $i++) {
+      // Place the same block again and make sure we have a new ID.
+      $this->drupalPost('admin/structure/block/add/views_block:test_view_block-block_1/' . $default_theme, array(), t('Save block'));
+      $blocks = $storage->load(array('stark.views_block__test_view_block_block_1_' . $i));
+      // This will only return a result if our new block has been created with the
+      // expected machine name.
+      $this->assertTrue(!empty($blocks), 'The expected block was loaded.');
+    }
   }
 
   /**

core/modules/views/lib/Drupal/views/Plugin/Block/ViewsBlock.php

@@ -10,6 +10,7 @@ namespace Drupal\views\Plugin\Block;
 use Drupal\block\BlockBase;
 use Drupal\Component\Annotation\Plugin;
 use Drupal\Core\Annotation\Translation;
+use Drupal\Core\Entity\EntityStorageControllerInterface;
 
 /**
  * Provides a generic Views block.
@@ -112,4 +113,34 @@ class ViewsBlock extends BlockBase {
     }
   }
 
+  /**
+   * Generates a views block instance ID.
+   *
+   * @param \Drupal\Core\Entity\EntityStorageControllerInterface $manager
+   *   The block storage controller.
+   *
+   * @return string
+   *   The new block instance ID.
+   */
+   public function generateBlockInstanceID(EntityStorageControllerInterface $manager) {
+     $this->view->setDisplay($this->displayID);
+     $original_id = 'views_block__' . $this->view->storage->id() . '_' . $this->view->current_display;
+
+     // Get an array of block IDs without the theme prefix.
+     $block_ids = array_map(function ($block_id) {
+       $parts = explode('.', $block_id);
+       return end($parts);
+     }, array_keys($manager->load()));
+
+     // Iterate through potential IDs until we get a new one. E.g.
+     // 'views_block__MYVIEW_PAGE_1_2'
+     $count = 1;
+     $id = $original_id;
+     while (in_array($id, $block_ids)) {
+       $id = $original_id . '_' . ++$count;
+     }
+
+     return $id;
+   }
+
 }

core/modules/views/lib/Drupal/views/Tests/Plugin/ViewsBlockTest.php

@@ -0,0 +1,86 @@
+<?php
+
+/**
+ * @file
+ * Contains \Drupal\views\Tests\Plugin\ViewsBlockTest.
+ */
+
+namespace Drupal\views\Tests\Plugin;
+
+use Drupal\Core\DependencyInjection\ContainerBuilder;
+use Drupal\views\Plugin\Block\ViewsBlock;
+use Drupal\views\Tests\ViewTestData;
+use Drupal\views\Tests\ViewUnitTestBase;
+
+/**
+ * Tests the block views plugin.
+ */
+class ViewsBlockTest extends ViewUnitTestBase {
+
+  /**
+   * Modules to enable.
+   *
+   * @var array
+   */
+  public static $modules = array('block', 'block_test_views');
+
+  /**
+   * Views used by this test.
+   *
+   * @var array
+   */
+  public static $testViews = array('test_view_block');
+
+  public static function getInfo() {
+    return array(
+      'name' => 'Views block',
+      'description' => 'Tests the block views plugin.',
+      'group' => 'Views Plugins',
+    );
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    parent::setUp();
+
+    ViewTestData::importTestViews(get_class($this), array('block_test_views'));
+  }
+
+  /**
+   * Tests generateBlockInstanceID.
+   *
+   * @see \Drupal\views\Plugin\Block::generateBlockInstanceID().
+   */
+  public function testGenerateBlockInstanceID() {
+
+    $plugin_definition = array(
+      'module' => 'views',
+    );
+    $plugin_id = 'views_block:test_view_block-block_1';
+    $views_block = new ViewsBlock(array(), $plugin_id, $plugin_definition);
+
+    $storage_controller = $this->container->get('plugin.manager.entity')->getStorageController('block');
+
+    // Generate a instance ID on a block without any instances.
+    $this->assertEqual($views_block->generateBlockInstanceID($storage_controller), 'views_block__test_view_block_block_1');
+
+    $values = array(
+      'plugin' => $plugin_id,
+      'id' => 'stark.views_block__test_view_block_block_1',
+      'module' => 'views',
+      'settings' => array(
+        'module' => 'views',
+      )
+    );
+    $storage_controller->create($values)->save();
+    $this->assertEqual($views_block->generateBlockInstanceID($storage_controller), 'views_block__test_view_block_block_1_2');
+
+    // Add another one block instance and ensure the block instance went up.
+    $values['id'] = 'stark.views_block__test_view_block_block_1_2';
+    $storage_controller->create($values)->save();
+    $this->assertEqual($views_block->generateBlockInstanceID($storage_controller), 'views_block__test_view_block_block_1_3');
+  }
+
+}

core/modules/views/views.module

@@ -1729,3 +1729,26 @@ function views_cache_get($cid, $use_language = FALSE) {
 
   return cache('views_info')->get($cid);
 }
+
+/**
+ * Implements hook_form_FORM_ID_alter for block_form().
+ *
+ * Views overrides block configuration form elements during
+ * \Drupal\views\Plugin\Block\ViewsBlock::form() but machine_name assignment is
+ * added later by \Drupal\block\BlockFormController::form() so we provide an
+ * override for the block machine_name here.
+ */
+function views_form_block_form_alter(&$form, &$form_state) {
+  // Ensure the block-form being altered is a Views block configuration form.
+  if (($form['settings']['module']['#value'] == 'views') && empty($form['machine_name']['#default_value'])) {
+    // Unset the machine_name provided by BlockFormController.
+    unset($form['machine_name']['#machine_name']['source']);
+    // Load the Views plugin object using form_state array and create a
+    // block machine_name based on the View ID and View Display ID.
+    $block_plugin = $form_state['controller']->getEntity()->getPlugin();
+    // Override the Views block's machine_name by providing a default_value.
+    $form['machine_name']['#default_value'] = $block_plugin->generateBlockInstanceID(Drupal::entityManager()->getStorageController('block'));
+    // Prevent users from changing the auto-generated block machine_name.
+    $form['machine_name']['#access'] = FALSE;
+  }
+}