[BUGFIX] Set IDs on Record Data when mutating DS Model (#6775)

packages/-ember-data/tests/unit/model-test.js

@@ -372,6 +372,13 @@ module('unit/model - Model', function(hooks) {
       assert.equal(idChange, 0);
       person._internalModel.setId('john');
       assert.equal(idChange, 1);
+      let recordData = recordDataFor(person);
+      assert.equal(
+        recordData.getResourceIdentifier().id,
+        'john',
+        'new id should be set on the identifier on record data.'
+      );
+      assert.equal(recordData.id, 'john', 'new id should be correctly set on the record data itself.');
       assert.equal(person.get('id'), 'john', 'new id should be correctly set.');
     });
 

packages/record-data/addon/-private/record-data.ts

@@ -430,6 +430,13 @@ export default class RecordDataDefault implements RelationshipRecordData {
     }
   }
 
+  // internal set coming from the model
+  __setId(id: string) {
+    if (this.id !== id) {
+      this.id = id;
+    }
+  }
+
   getAttr(key: string): string {
     if (key in this._attributes) {
       return this._attributes[key];

packages/store/addon/-private/system/model/internal-model.ts

@@ -1369,6 +1369,10 @@ export default class InternalModel {
 
     if (didChange && id !== null) {
       this.store.setRecordId(this.modelName, id, this.clientId);
+      // internal set of ID to get it to RecordData from DS.Model
+      if (this._recordData.__setId) {
+        this._recordData.__setId(id);
+      }
     }
 
     if (didChange && this.hasRecord) {

packages/store/addon/-private/ts-interfaces/record-data.ts

@@ -61,4 +61,7 @@ export default interface RecordData {
   isDeletionCommitted?(): boolean;
 
   setIsDeleted?(isDeleted: boolean): void;
+
+  // Private and experimental
+  __setId?(id: string): void;
 }