getLibrary example

// Ensure $build only contains defined regions and in the order defined.     $build = [];
    foreach ($this->getPluginDefinition()->getRegionNames() as $region_name) {
      if (array_key_exists($region_name, $regions)) {
        $build[$region_name] = $regions[$region_name];
      }
    }
    $build['#in_preview'] = $this->inPreview;
    $build['#settings'] = $this->getConfiguration();
    $build['#layout'] = $this->pluginDefinition;
    $build['#theme'] = $this->pluginDefinition->getThemeHook();
    if ($library = $this->pluginDefinition->getLibrary()) {
      $build['#attached']['library'][] = $library;
    }
    return $build;
  }

  /** * {@inheritdoc} */
  public function getConfiguration() {
    return $this->configuration;
  }

  

$path = $definition->getPath();
    $path = !empty($path) ? $base_path . '/' . $path : $base_path;
    $definition->setPath($path);

    // Add the base path to the icon path.     if ($icon_path = $definition->getIconPath()) {
      $definition->setIconPath($path . '/' . $icon_path);
    }

    // Add a dependency on the provider of the library.     if ($library = $definition->getLibrary()) {
      $config_dependencies = $definition->getConfigDependencies();
      [$library_provider] = explode('/', $library, 2);
      if ($this->moduleHandler->moduleExists($library_provider)) {
        $config_dependencies['module'][] = $library_provider;
      }
      elseif ($this->themeHandler->themeExists($library_provider)) {
        $config_dependencies['theme'][] = $library_provider;
      }
      $definition->setConfigDependencies($config_dependencies);
    }

    

public function testGetDefinition() {
    $layout_definition = $this->layoutPluginManager->getDefinition('theme_a_provided_layout');
    $this->assertSame('theme_a_provided_layout', $layout_definition->id());
    $this->assertSame('2 column layout', (string) $layout_definition->getLabel());
    $this->assertSame('Columns: 2', (string) $layout_definition->getCategory());
    $this->assertSame('A theme provided layout', (string) $layout_definition->getDescription());
    $this->assertInstanceOf(TranslatableMarkup::class, $layout_definition->getLabel());
    $this->assertInstanceOf(TranslatableMarkup::class, $layout_definition->getCategory());
    $this->assertInstanceOf(TranslatableMarkup::class, $layout_definition->getDescription());
    $this->assertSame('twocol', $layout_definition->getTemplate());
    $this->assertSame('themes/theme_a/templates', $layout_definition->getPath());
    $this->assertSame('theme_a/twocol', $layout_definition->getLibrary());
    $this->assertSame('twocol', $layout_definition->getThemeHook());
    $this->assertSame('themes/theme_a/templates', $layout_definition->getTemplatePath());
    $this->assertSame('theme_a', $layout_definition->getProvider());
    $this->assertSame('right', $layout_definition->getDefaultRegion());
    $this->assertSame(LayoutDefault::class, $layout_definition->getClass());
    $expected_regions = [
      'left' => [
        'label' => new TranslatableMarkup('Left region', [], ['context' => 'layout_region']),
      ],
      'right' => [
        'label' => new TranslatableMarkup('Right region', [], ['context' => 'layout_region']),
      ],