1 files changed, 20 insertions, 1 deletions

diff --git a/src/data/things/index.js b/src/data/things/index.js
index 9f033c23..17471f31 100644
--- a/src/data/things/index.js
+++ b/src/data/things/index.js
@@ -6,6 +6,7 @@ import CacheableObject from '#cacheable-object';
 import {logError} from '#cli';
 import {compositeFrom} from '#composite';
 import * as serialize from '#serialize';
+import {withEntries} from '#sugar';
 import Thing from '#thing';
 
 import * as albumClasses from './album.js';
@@ -17,6 +18,7 @@ import * as groupClasses from './group.js';
 import * as homepageLayoutClasses from './homepage-layout.js';
 import * as languageClasses from './language.js';
 import * as newsEntryClasses from './news-entry.js';
+import * as sortingRuleClasses from './sorting-rule.js';
 import * as staticPageClasses from './static-page.js';
 import * as trackClasses from './track.js';
 import * as wikiInfoClasses from './wiki-info.js';
@@ -31,6 +33,7 @@ const allClassLists = {
   'homepage-layout.js': homepageLayoutClasses,
   'language.js': languageClasses,
   'news-entry.js': newsEntryClasses,
+  'sorting-rule.js': sortingRuleClasses,
   'static-page.js': staticPageClasses,
   'track.js': trackClasses,
   'wiki-info.js': wikiInfoClasses,
@@ -79,13 +82,25 @@ function errorDuplicateClassNames() {
 }
 
 function flattenClassLists() {
+  let allClassesUnsorted = Object.create(null);
+
   for (const classes of Object.values(allClassLists)) {
     for (const [name, constructor] of Object.entries(classes)) {
       if (typeof constructor !== 'function') continue;
       if (!(constructor.prototype instanceof Thing)) continue;
-      allClasses[name] = constructor;
+      allClassesUnsorted[name] = constructor;
     }
   }
+
+  // Sort subclasses after their superclasses.
+  Object.assign(allClasses,
+    withEntries(allClassesUnsorted, entries =>
+      entries.sort(({[1]: A}, {[1]: B}) =>
+        (A.prototype instanceof B
+          ? +1
+       : B.prototype instanceof A
+          ? -1
+          :  0))));
 }
 
 function descriptorAggregateHelper({
@@ -184,6 +199,10 @@ function finalizeCacheableObjectPrototypes() {
     op(constructor) {
       constructor.finalizeCacheableObjectPrototype();
     },
+
+    showFailedClasses(failedClasses) {
+      logError`Failed to finalize cacheable object prototypes for classes: ${failedClasses.join(', ')}`;
+    },
   });
 }