Issue #3357502: CMDocument: Add support for documenting base fields

src/DocumentableEntityProvider.php

@@ -231,6 +231,11 @@ class DocumentableEntityProvider extends ServiceProviderBase {
         }
         foreach ($element['bundles'] as $bundle_name) {
           $documentable_entities["{$entity_type}.{$bundle_name}.{$element_name}"] = "{$entity_type}.{$bundle_name}.{$element_name}";
+          // Add base field if it has not already been added.
+          $base_field_name = "base.field.{$element_name}";
+          if (!isset($documentable_entities[$base_field_name])) {
+            $documentable_entities[$base_field_name] = $base_field_name;
+          }
         }
       }
 

src/Entity/CMDocument.php

@@ -402,6 +402,11 @@ class CMDocument extends EditorialContentEntityBase implements CMDocumentInterfa
     $field = $this->getDocumentedEntityParameter('field');
 
     switch ($type) {
+      case 'base':
+        // Field bases don't have an admin path, so path it to CM Document.
+        $alias = "/admin/structure/cm_document/{$type}/{$bundle_hyphenated}/{$field}";
+        break;
+
       case 'block_content':
         $alias = "/admin/structure/block/block-content/manage/{$bundle}/fields/block_content.{$bundle}.{$field}/document";
         break;

src/Form/CMDocumentForm.php

@@ -210,6 +210,12 @@ class CMDocumentForm extends ContentEntityForm {
       $module = $document->getDocumentedEntityParameter('module');
       return ($project === $module) ? "Module: {$project}" : "Module: {$project}: {$module}";
     }
+    elseif ($entity_type === 'base') {
+      // This is a base field and has no name by itself.
+      $fieldname = $document->getDocumentedEntityParameter('field');
+      return "Base field: {$fieldname}";
+
+    }
     else {
       // This is a real entity.
       $bundlename = $document->getDocumentedEntityParameter('bundle');