Use input as id for unvisitEntity

src/__tests__/__snapshots__/index.test.js.snap

@@ -35,6 +35,23 @@ Object {
 }
 `;
 
+exports[`denormalize denormalizes with function as idAttribute 1`] = `
+Array [
+  Object {
+    "guest": null,
+    "id": "1",
+    "name": "Esther",
+  },
+  Object {
+    "guest": Object {
+      "guest_id": 1,
+    },
+    "id": "2",
+    "name": "Tom",
+  },
+]
+`;
+
 exports[`normalize can use fully custom entity classes 1`] = `
 Object {
   "entities": Object {

src/__tests__/index.test.js

@@ -224,4 +224,27 @@ describe('denormalize', () => {
     });
     expect(() => denormalize('123', article, entities)).not.toThrow();
   });
+
+  it('denormalizes with function as idAttribute', () => {
+    const normalizedData = {
+      'entities': {
+        'patrons': {
+          '1': { 'id': '1', 'guest': null, 'name': 'Esther' },
+          '2': { 'id': '2', 'guest': 'guest-2-1', 'name': 'Tom' }
+        },
+        'guests': { 'guest-2-1': { 'guest_id': 1 } }
+      },
+      'result': [ '1', '2' ]
+    };
+
+    const guestSchema = new schema.Entity('guests', {}, {
+      idAttribute: (value, parent, key) => `${key}-${parent.id}-${value.guest_id}`
+    });
+
+    const patronsSchema = new schema.Entity('patrons', {
+      guest: guestSchema
+    });
+
+    expect(denormalize(normalizedData.result, [ patronsSchema ], normalizedData.entities)).toMatchSnapshot();
+  });
 });

src/index.js

@@ -53,14 +53,12 @@ export const normalize = (input, schema) => {
   return { entities, result };
 };
 
-const unvisitEntity = (input, schema, unvisit, getEntity, cache) => {
-  const entity = getEntity(input, schema);
+const unvisitEntity = (id, schema, unvisit, getEntity, cache) => {
+  const entity = getEntity(id, schema);
   if (typeof entity !== 'object' || entity === null) {
     return entity;
   }
 
-  const id = schema.getId(entity);
-
   if (!cache[schema.key]) {
     cache[schema.key] = {};
   }