Fixed merge JsValues when field is absent in old value (#153)v1.8.21

2 files changed, 13 insertions, 4 deletions

diff --git a/src/main/scala/xyz/driver/core/rest/PatchDirectives.scala b/src/main/scala/xyz/driver/core/rest/PatchDirectives.scala
index 256358c..f33bf9d 100644
--- a/src/main/scala/xyz/driver/core/rest/PatchDirectives.scala
+++ b/src/main/scala/xyz/driver/core/rest/PatchDirectives.scala
@@ -53,10 +53,10 @@ trait PatchDirectives extends Directives with SprayJsonSupport {
   }
 
   protected def mergeObjects(oldObj: JsObject, newObj: JsObject, maxLevels: Option[Int] = None): JsObject = {
-    JsObject(oldObj.fields.map({
-      case (key, oldValue) =>
-        val newValue = newObj.fields.get(key).fold(oldValue)(mergeJsValues(oldValue, _, maxLevels.map(_ - 1)))
-        key -> newValue
+    JsObject((oldObj.fields.keys ++ newObj.fields.keys).map({ key =>
+      val oldValue = oldObj.fields.getOrElse(key, JsNull)
+      val newValue = newObj.fields.get(key).fold(oldValue)(mergeJsValues(oldValue, _, maxLevels.map(_ - 1)))
+      key -> newValue
     })(collection.breakOut): _*)
   }
 
diff --git a/src/test/scala/xyz/driver/core/rest/PatchDirectivesTest.scala b/src/test/scala/xyz/driver/core/rest/PatchDirectivesTest.scala
index 6a6b035..987717d 100644
--- a/src/test/scala/xyz/driver/core/rest/PatchDirectivesTest.scala
+++ b/src/test/scala/xyz/driver/core/rest/PatchDirectivesTest.scala
@@ -72,6 +72,15 @@ class PatchDirectivesTest
     }
   }
 
+  it should "handle optional values correctly when old value is null" in {
+    val fooRetrieve = Future.successful(Some(testFoo.copy(bar = None)))
+
+    Patch("/api/v1/foos/1", jsonEntity("""{"bar": {"name": "My Bar","size":10}}""")) ~> route(fooRetrieve) ~> check {
+      handled shouldBe true
+      responseAs[Foo] shouldBe testFoo.copy(bar = Some(Bar(Name("My Bar"), 10)))
+    }
+  }
+
   it should "return a 400 for nulls on non-optional values" in {
     val fooRetrieve = Future.successful(Some(testFoo))