Issue #3435933 by yassrzg, Grimreaper, pdureau: Introducing dependencies between themes

src/Definition/ThemeDefinition.php

@@ -26,6 +26,7 @@ class ThemeDefinition extends PluginDefinition {
     'library' => '',
     'additional' => [],
     'provider' => '',
+    'dependencies' => [],
   ];
 
   /**
@@ -241,6 +242,29 @@ class ThemeDefinition extends PluginDefinition {
     return $this;
   }
 
+  /**
+   * Getter.
+   *
+   * @return array
+   *   Property value.
+   */
+  public function getDependencies(): array {
+    return $this->definition['dependencies'];
+  }
+
+  /**
+   * Setter.
+   *
+   * @param array $dependencies
+   *   Property value.
+   *
+   * @return $this
+   */
+  public function setDependencies(array $dependencies) {
+    $this->definition['dependencies'] = $dependencies;
+    return $this;
+  }
+
   /**
    * Return array definition.
    *

src/HookHandler/PreprocessHtml.php

@@ -48,31 +48,28 @@ class PreprocessHtml implements ContainerInjectionInterface {
       return;
     }
 
-    /** @var \Drupal\ui_skins\Definition\ThemeDefinition $plugin_definition */
-    $plugin_definition = $this->themePluginManager->getDefinition($ui_skins_theme_setting, FALSE);
-    if ($plugin_definition == NULL) {
-      return;
-    }
+    $definitions = $this->themePluginManager->getDefinitionWithDependencies($ui_skins_theme_setting);
+    foreach ($definitions as $definition) {
+      $target = $definition->getComputedTarget();
+      $key = $definition->getKey();
+      $value = $definition->getValue();
+      if ($key == 'class') {
+        $value = [
+          Html::getClass($value),
+        ];
+      }
 
-    $target = $plugin_definition->getComputedTarget();
-    $key = $plugin_definition->getKey();
-    $value = $plugin_definition->getValue();
-    if ($key == 'class') {
-      $value = [
-        Html::getClass($value),
-      ];
-    }
-
-    $variables[$target] = AttributeHelper::mergeCollections(
-      $variables[$target],
-      [
-        $key => $value,
-      ]
-    );
+      $variables[$target] = AttributeHelper::mergeCollections(
+        $variables[$target] ?? [],
+        [
+          $key => $value,
+        ]
+      );
 
-    $library = $plugin_definition->getLibrary();
-    if (!empty($library)) {
-      $variables['#attached']['library'][] = $library;
+      $library = $definition->getLibrary();
+      if (!empty($library)) {
+        $variables['#attached']['library'][] = $library;
+      }
     }
   }
 

src/Theme/ThemePluginManager.php

@@ -53,6 +53,7 @@ class ThemePluginManager extends DefaultPluginManager implements ThemePluginMana
       'key' => 'class',
       'value' => '',
       'library' => '',
+      'dependencies' => [],
     ];
   }
 
@@ -121,4 +122,26 @@ class ThemePluginManager extends DefaultPluginManager implements ThemePluginMana
     return $definitions;
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function getDefinitionWithDependencies(string $pluginId): array {
+    $definitions = [];
+
+    $definition = $this->getDefinition($pluginId, FALSE);
+    if ($definition == NULL) {
+      return $definitions;
+    }
+
+    // Handle dependencies.
+    $dependencies = $definition->getDependencies();
+    foreach ($dependencies as $dependency) {
+      $definitions = \array_merge($definitions, $this->getDefinitionWithDependencies($dependency));
+    }
+
+    // Add our initial target last.
+    $definitions[] = $definition;
+    return $definitions;
+  }
+
 }

src/Theme/ThemePluginManagerInterface.php

@@ -40,4 +40,15 @@ interface ThemePluginManagerInterface extends PluginManagerInterface {
    */
   public function getDefinitionsForTheme(string $theme): array;
 
+  /**
+   * Get the plugin definition with its dependencies.
+   *
+   * @param string $pluginId
+   *   A plugin id.
+   *
+   * @return \Drupal\ui_skins\Definition\ThemeDefinition[]
+   *   The plugin definitions.
+   */
+  public function getDefinitionWithDependencies(string $pluginId): array;
+
 }

tests/modules/ui_skins_test/src/DummyThemePluginManager.php

@@ -28,6 +28,7 @@ class DummyThemePluginManager extends ThemePluginManager {
     foreach ($definitions as $plugin_id => &$definition) {
       $this->processDefinition($definition, $plugin_id);
     }
+    $this->definitions = $definitions;
     return $definitions;
   }
 

tests/src/Functional/ThemeTest.php

@@ -198,6 +198,13 @@ class ThemeTest extends UiSkinsFunctionalTestBase {
     $this->drupalGet(Url::fromRoute('<front>'));
     $this->assertSession()->elementExists('css', 'body.test-7');
     $this->assertSession()->responseContains('href="' . Url::fromUserInput('/' . $ui_skins_test_themes_path . '/assets/css/test.css')->toString());
+
+    \drupal_flush_all_caches();
+    $this->setTheme('test_8');
+    $this->drupalGet(Url::fromRoute('<front>'));
+    $this->assertSession()->elementExists('css', 'body.test-7.test-8');
+    $this->assertSession()->responseContains('href="' . Url::fromUserInput('/' . $ui_skins_test_themes_path . '/assets/css/test.css')->toString());
+    $this->assertSession()->responseContains('href="' . Url::fromUserInput('/' . $ui_skins_test_themes_path . '/assets/css/test_8.css')->toString());
   }
 
   /**

tests/src/Unit/ThemePluginManagerTest.php

@@ -116,4 +116,70 @@ class ThemePluginManagerTest extends UnitTestCase {
     $this->assertEquals($definition->toArray(), $expected->toArray());
   }
 
+  /**
+   * Tests the getDefinitionWithDependencies().
+   *
+   * @covers ::getDefinitionWithDependencies
+   */
+  public function testGetDefinitionWithDependencies(): void {
+    $themes = [
+      'no_dependencies' => [
+        'id' => 'no_dependencies',
+        'label' => 'No dependencies',
+        'value' => 'foo',
+      ],
+      'with_dependencies' => [
+        'id' => 'with_dependencies',
+        'label' => 'With dependencies',
+        'value' => 'foo',
+        'dependencies' => [
+          'dependency_1',
+          'dependency_2',
+        ],
+      ],
+      'dependency_1' => [
+        'id' => 'dependency_1',
+        'label' => 'Dependency 1',
+        'value' => 'foo',
+        'dependencies' => [
+          'dependency_1_1',
+        ],
+      ],
+      'dependency_1_1' => [
+        'id' => 'dependency_1_1',
+        'label' => 'Dependency 1 1',
+        'value' => 'foo',
+      ],
+      'dependency_2' => [
+        'id' => 'dependency_2',
+        'label' => 'Dependency 2',
+        'value' => 'foo',
+      ],
+    ];
+    $this->themePluginManager->setThemes($themes);
+
+    $definitions = $this->themePluginManager->getDefinitionWithDependencies('no_dependencies');
+    $this->assertCount(1, $definitions);
+    $this->assertInstanceOf(ThemeDefinition::class, $definitions[0]);
+    $this->assertSame('No dependencies', $definitions[0]->getLabel());
+
+    $definitions = $this->themePluginManager->getDefinitionWithDependencies('dependency_1');
+    $this->assertCount(2, $definitions);
+    $this->assertInstanceOf(ThemeDefinition::class, $definitions[0]);
+    $this->assertSame('Dependency 1 1', $definitions[0]->getLabel());
+    $this->assertInstanceOf(ThemeDefinition::class, $definitions[1]);
+    $this->assertSame('Dependency 1', $definitions[1]->getLabel());
+
+    $definitions = $this->themePluginManager->getDefinitionWithDependencies('with_dependencies');
+    $this->assertCount(4, $definitions);
+    $this->assertInstanceOf(ThemeDefinition::class, $definitions[0]);
+    $this->assertSame('Dependency 1 1', $definitions[0]->getLabel());
+    $this->assertInstanceOf(ThemeDefinition::class, $definitions[1]);
+    $this->assertSame('Dependency 1', $definitions[1]->getLabel());
+    $this->assertInstanceOf(ThemeDefinition::class, $definitions[2]);
+    $this->assertSame('Dependency 2', $definitions[2]->getLabel());
+    $this->assertInstanceOf(ThemeDefinition::class, $definitions[3]);
+    $this->assertSame('With dependencies', $definitions[3]->getLabel());
+  }
+
 }

tests/themes/ui_skins_test_themes/assets/css/test_8.css

+.fake {
+  background-color: red;
+}

tests/themes/ui_skins_test_themes/ui_skins_test_themes.libraries.yml

@@ -2,3 +2,8 @@ theme:
   css:
     theme:
       assets/css/test.css: {}
+
+test_8:
+  css:
+    theme:
+      assets/css/test_8.css: {}

tests/themes/ui_skins_test_themes/ui_skins_test_themes.ui_skins.themes.yml

@@ -34,3 +34,11 @@ test_6:
 test_7:
   label: "(implicit) Body class with library"
   library: "ui_skins_test_themes/theme"
+
+# <body class="test-7 test-8">
+# Test dependency.
+test_8:
+  label: "Test dependency"
+  library: "ui_skins_test_themes/test_8"
+  dependencies:
+    - test_7