fix: improved the spec of the function to respect nil values (reported by eseres)

Author: zookzook

lib/mongo/results.ex

@@ -73,9 +73,9 @@ defmodule Mongo.FindAndModifyResult do
   """
 
   @type t :: %__MODULE__{
-          value: BSON.document(),
+          value: BSON.document() | nil,
           matched_count: non_neg_integer(),
-          upserted_id: String.t(),
+          upserted_id: String.t() | nil,
           updated_existing: boolean()
         }
 

test/mongo/find_one_test.exs

@@ -16,4 +16,29 @@ defmodule Mongo.FindOneTest do
     assert %{"name" => "Oska"} == Mongo.find_one(top, coll, %{}, sort: %{age: 1}) |> Map.take(["name"])
     assert %{"name" => "Tom"} == Mongo.find_one(top, coll, %{}, sort: %{age: -1}) |> Map.take(["name"])
   end
+
+  test "find_one_and_update", %{pid: top} do
+    coll = unique_collection()
+    Mongo.insert_one(top, coll, %{name: "Greta", age: 10})
+
+    assert {:ok,
+            %Mongo.FindAndModifyResult{
+              value: %{
+                "_id" => _id,
+                "age" => 10,
+                "name" => "Greta"
+              },
+              matched_count: 1,
+              upserted_id: nil,
+              updated_existing: true
+            }} = Mongo.find_one_and_update(top, coll, %{name: "Greta"}, %{"$set": %{age: 14}})
+
+    assert {:ok,
+            %Mongo.FindAndModifyResult{
+              value: nil,
+              matched_count: 0,
+              upserted_id: nil,
+              updated_existing: false
+            }} = Mongo.find_one_and_update(top, coll, %{name: "Greta-2"}, %{"$set": %{age: 14}})
+  end
 end