FIX: Hydration of embedded records (#22809)

The store expects values for property names ending with `_id` to be a resource id
and `_ids` to be an array of resource ids.

This change ensures the store gracefully handles situations where an
embedded field with incompliant data structure sneaks its way to production.

app/assets/javascripts/discourse/app/services/store.js

@@ -6,6 +6,7 @@ import ResultSet from "discourse/models/result-set";
 import { ajax } from "discourse/lib/ajax";
 import { getRegister } from "discourse-common/lib/get-owner";
 import { underscore } from "@ember/string";
+import { warn } from "@ember/debug";
 
 let _identityMap;
 
@@ -325,9 +326,18 @@ export default Service.extend({
         const subType = m[1];
 
         if (m[2]) {
+          if (!Array.isArray(obj[k])) {
+            warn(`Expected an array of resource ids for ${type}.${k}`, {
+              id: "discourse.store.hydrate-embedded",
+            });
+
+            return;
+          }
+
           const hydrated = obj[k].map((id) =>
             this._lookupSubType(subType, type, id, root)
           );
+
           obj[this.pluralize(subType)] = hydrated || [];
           delete obj[k];
         } else {

app/assets/javascripts/discourse/tests/helpers/store-pretender.js

@@ -12,7 +12,14 @@ const fruits = [
   { id: 1, name: "apple", farmer_id: 1, color_ids: [1, 2], category_id: 4 },
   { id: 2, name: "banana", farmer_id: 1, color_ids: [3], category_id: 3 },
   { id: 3, name: "grape", farmer_id: 2, color_ids: [2], category_id: 5 },
-  { id: 4, name: "orange", farmer_id: null, color_ids: [2], category_id: 5 },
+  {
+    id: 4,
+    name: "orange",
+    farmer_id: null,
+    color_ids: [2],
+    category_id: 5,
+    other_fruit_ids: { apple: 1, banana: 2 },
+  },
 ];
 
 const farmers = [

app/assets/javascripts/discourse/tests/unit/services/store-test.js

@@ -263,4 +263,15 @@ module("Unit | Service | store", function (hooks) {
     assert.true(Array.isArray(result.topics));
     assert.strictEqual(result.filter, "topics/created-by/trout");
   });
+
+  test("Spec incompliant embedded record name", async function (assert) {
+    const store = getOwner(this).lookup("service:store");
+    const fruit = await store.find("fruit", 4);
+
+    assert.propContains(
+      fruit.other_fruit_ids,
+      { apple: 1, banana: 2 },
+      "embedded record remains unhydrated"
+    );
+  });
 });