From 98b96cd44536c2b475806b9d2ef234051d5cbceb Mon Sep 17 00:00:00 2001
From: Christoffer Persson <christoffer@valdoo.se>
Date: Sun, 31 May 2015 14:06:12 +0300
Subject: [PATCH] Guard for embedded unknown hasMany relationship

---
 .../lib/serializers/embedded-records-mixin.js |  8 ++++--
 .../embedded-records-mixin-test.js            | 26 +++++++++++++++++++
 2 files changed, 32 insertions(+), 2 deletions(-)

diff --git a/packages/ember-data/lib/serializers/embedded-records-mixin.js b/packages/ember-data/lib/serializers/embedded-records-mixin.js
index d0c2be79e37..7a1a94fda6c 100644
--- a/packages/ember-data/lib/serializers/embedded-records-mixin.js
+++ b/packages/ember-data/lib/serializers/embedded-records-mixin.js
@@ -299,13 +299,17 @@ var EmbeddedRecordsMixin = Ember.Mixin.create({
     }
     var includeIds = this.hasSerializeIdsOption(attr);
     var includeRecords = this.hasSerializeRecordsOption(attr);
-    var key;
+    var key, hasMany;
     if (includeIds) {
       key = this.keyForRelationship(attr, relationship.kind, 'serialize');
       json[key] = snapshot.hasMany(attr, { ids: true });
     } else if (includeRecords) {
       key = this.keyForAttribute(attr, 'serialize');
-      json[key] = snapshot.hasMany(attr).map(function(embeddedSnapshot) {
+      hasMany = snapshot.hasMany(attr);
+
+      Ember.warn("The relationship '" + key + "' is unknown for '" + snapshot.modelName + "' with id '" + snapshot.id + "'. Please include it in your original payload.", Ember.typeOf(hasMany) !== 'undefined');
+
+      json[key] = Ember.A(hasMany).map(function(embeddedSnapshot) {
         var embeddedJson = embeddedSnapshot.record.serialize({ includeId: true });
         this.removeEmbeddedForeignKey(snapshot, embeddedSnapshot, relationship, embeddedJson);
         return embeddedJson;
diff --git a/packages/ember-data/tests/integration/serializers/embedded-records-mixin-test.js b/packages/ember-data/tests/integration/serializers/embedded-records-mixin-test.js
index 8606df6b8a8..88a5ef1a876 100644
--- a/packages/ember-data/tests/integration/serializers/embedded-records-mixin-test.js
+++ b/packages/ember-data/tests/integration/serializers/embedded-records-mixin-test.js
@@ -609,6 +609,32 @@ test("serialize with embedded objects (hasMany relationship)", function() {
   });
 });
 
+test("serialize with embedded objects (unknown hasMany relationship)", function() {
+  var league;
+  run(function() {
+    league = env.store.push(HomePlanet, { name: "Villain League", id: "123" });
+  });
+
+  env.registry.register('serializer:home-planet', DS.ActiveModelSerializer.extend(DS.EmbeddedRecordsMixin, {
+    attrs: {
+      villains: { embedded: 'always' }
+    }
+  }));
+
+  var serializer, json;
+  warns(function() {
+    run(function() {
+      serializer = env.container.lookup("serializer:home-planet");
+      json = serializer.serialize(league._createSnapshot());
+    });
+  }, /The relationship 'villains' is unknown for 'home-planet' with id '123'. Please include it in your original payload./);
+
+  deepEqual(json, {
+    name: "Villain League",
+    villains: []
+  });
+});
+
 test("serialize with embedded objects (hasMany relationship) supports serialize:false", function() {
   run(function() {
     league = env.store.createRecord(HomePlanet, { name: "Villain League", id: "123" });