fix(refs): updated collection should not contain DocumentReference

it's important to always put plain by extracting the refs from documents before setting the
information in the array or document

src/index.js

@@ -31,6 +31,7 @@ function subscribeToRefs ({
     const ref = refs[refKey]
 
     // documents are fully replaced so it's necessary to bind things again
+    // TODO it would be nice to prevent unnecessary unbind
     if (sub) sub.unbind()
 
     // maybe wrap the unbind function to call unbind on every child
@@ -91,8 +92,8 @@ function bindCollection ({
       arraySubs.splice(newIndex, 0, subs)
       array.splice(oldIndex, 1)
       const snapshot = createSnapshot(doc)
-      array.splice(newIndex, 0, snapshot)
       const [data, refs] = extractRefs(snapshot)
+      array.splice(newIndex, 0, data)
       subscribeToRefs({
         data,
         refs,

test/refs-collections.spec.js

@@ -137,3 +137,15 @@ test('updates when modifying an item', async () => {
     { ref: { isB: true }}
   ])
 })
+
+test('removes the DocumentReference when modifying an item', async () => {
+  await vm.$bind('items', collection)
+  await first.update({ newThing: true })
+
+  expect(typeof vm.items[0].ref).toBe('string')
+  await delay(5)
+  expect(vm.items[0]).toEqual({
+    ref: { isA: true },
+    newThing: true
+  })
+})

test/refs-documents.spec.js

@@ -386,5 +386,4 @@ test('properly updates a documen with refs', async () => {
     newThing: true,
     a: { isA: true }
   })
-
 })